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INTRODUCTION TO PATHOLOGY59055025336500Introduction to Pathology?Michelle Cochrane 2015All rights reserved. This material is subject to copyright and may not be reprinted or reproduced in any manner without prior consent from the author.Reproduced by Om Shanti College with permission from the author for educational purposes only.CONTENTSLesson 1 IntroductionLesson 2: Cellular PathologyLesson 3: Neoplasia and CancerLesson 4: Homeostasis and Fluid BalanceLesson 5: Infectious DiseasesLesson 6: Musculoskeletal DisordersLesson 7: Integumentary Disorders Lesson 8: Eyes, Ears, Nose and ThroatLesson 9: Respiratory DisordersLesson 10: Cardiovascular DisordersLesson 11: Blood DisordersLesson 12: Immune System DisordersLesson 13: Digestive DisordersLesson 14: Urinary DisordersLesson 15: Reproductive DisordersLesson 16: Endocrine DisordersLesson 17: Nervous System DisordersLesson 18: Mental IllnessLESSON 1 – INTRODUCTIONWhat is PathologyCauses of DiseaseManifestationsTreatmentInflammation and HealingAcute InflammationChronic InflammationHealingWHAT IS PATHOLOGYWelcome to pathology. So what is it all about?A simple definition of pathology is:The study of disease processes with the aim of understanding their nature and causes.Clinical pathology is the application of this understanding in treating patients. Why do natural health practitioners need to know pathology? Every year, the number of people seeking help from a natural health practitioner increases. This could be a naturopath, homeopath, massage therapist, kinesiologist or any one of a wide range of different modalities. Many will seek a natural medicine solution without consulting a conventional doctor. This could be because their natural health practitioner has more time to spend with them, because they are looking for a holistic approach, or because they do not trust the conventional healthcare system. In these cases, it is especially important that the practitioner understands not only the condition that their client presents with but also the effects – good and bad – of any treatment. The first rule of all healthcare practitioners should be “first do no harm”. Doing harm could be something as simple as overworking an injured muscle during massage or passing on an infectious disease. It could also be something more serious like prescribing an herbal medicine which affects blood pressure to someone with a serious heart condition. The conditions which your client present to you may be simple or complex. They may be minor or serious. By understanding their condition you will know what treatment is appropriate, what is not appropriate, when you need to find further information and when you should refer on to someone with more appropriate qualifications and experience.All of this will make you a better practitioner. CAUSES OF DISEASEThe cause of disease is known as aetiology (US: etiology).There are three main causes of disease:Congenital causesAcquired causesUnknown causesCongenital conditionsCongenital conditions are those that are present at birth. These can arise from a number of different factors including:Genetics – a fault in the DNA of the developing foetus. There are two types:Hereditary – where one or both parents has a faulty gene which is then passed on to the child.Non-hereditary – both parents have normal DNA, but there is an error in transcription when the DNA is copied to the child.Environmental – varied factors including:Maternal infection or illnessMaternal nutritionMaternal smoking, alcohol or drug useIrradiationPlacental abnormalitiesAcquired conditionsAcquired conditions are those which are caused by events that occur after birth. These can include:InjuryInfections – viruses, bacteria, fungi, parasitesExposure to toxins:Environmental toxins e.g. air pollution, asbestos exposure, water pollutionIngested toxins e.g. drugs, alcoholLifestyle factorsInappropriate immune responsesMany diseases will have a combination of both genetic and environmental factors. A good example of this is breast cancer. Scientists have discovered a gene which makes women more susceptible to the disease, however there are many other factors that can increase the risk such as hormone treatments. Risk FactorsRisk factors do not necessarily cause a disease by themselves, but they make it more likely that the person will get the disease. Risk factors include things like:GeneticsEnvironmental exposure to toxinsLifestyle factors such as diet, exercise and obesityMANIFESTATIONSManifestations are how the disease presents itself. They are split into two groups:Signs are something that is externally visible or detectable.Symptoms are something that is felt or experienced by the patient.SignsSigns are the external manifestations of the disease. These could include physical characteristics such as a rash, jaundice, hair loss or obesity. It could also include physical disabilities such as a tremor or walking with a limp. Signs also include externally detectable signs of mental illness such as agitation or confused speech.SymptomsSymptoms are what the patient experiences. Physical symptoms include pain, itching and nausea. Mental symptoms include anxiety or paranoia.TREATMENTTreatment given will depend on a number of factors:The nature of the condition – some conditions are treatable and others are not, while the type of treatment will also vary.The patient themselves – their general health, stage of life, lifestyle, financial situation and treatment preferences.The practitioner - their modality and their level of expertise.Remember – the first rule of treatment is always do no harm. If in any doubt, do not treat the patient but refer them to someone who has more knowledge and experience of the condition that they are seeking treatment for.You should also always take into account any other treatment that they are receiving. Consider the effects of combining different treatments. Where the patient is under the treatment of a doctor or other healthcare professional such as a physiotherapist, always make sure that their doctor is aware of the treatment that you are giving. If they have a complicated medical condition or you are unsure of anything, ask the patient to provide a consent letter from their doctor before you treat them. INFLAMMATIONInflammation is an important part of the process of healing and fighting disease. You should have already studied inflammation as part of your anatomy and physiology studies but, seeing as it’s so important, let’s have another look. This time we will go into a bit more detail. The inflammatory response is the body’s reaction to injury. It involves neurological, vascular, fluid and cellular reactions. The main purpose of inflammation is to isolate or destroy the pathogen (the agent that is causing the injury), to remove damaged tissue and repair the damage. 1.5.1ACUTE INFLAMMATIONAcute inflammation is a rapid onset, short term response to injury from:Chemical agentsToxinsPathogens (bacteria, viruses etc.)TraumaHypersensitivity (allergic) reactionsTissue necrosis (tissue death)There are five key signs and symptoms of inflammation:Redness – caused by vasodilation and increased blood flow to the area.Heat – mainly in peripheral or surface areas of the body. Vasodilation increases the flow of warm blood to the area.Pain – partly from stretching of tissues due to oedema. Partly from effects of inflammatory chemicals such as prostaglandins and kinins. Swelling – vasodilation and increased permeability of blood vessels results in increased interstitial fluid in the area.Loss of function – pain results in a conscious or reflexive inhibition of movement. Swelling may also impede the ability to move joints. The purposes of inflammation are to:Prevent the spread of pathogens and toxins to surrounding tissuesDispose of pathogens and cell debrisAlert the adaptive immune systemInitiate the repair processThere are 3 stages to the inflammation process:Vascular stage-63551117500Cellular stageRepair stageVascular StageBlood vessels dilate allowing more blood flow to the affected area. As the capillaries expand, this also makes them more permeable – as they are stretched, so the gaps in the membrane become larger. This enables fluid, lymphocytes and various chemicals to pass from the capillaries to the surrounding tissues. This is what is responsible for causing the redness, heat and swelling associated with inflammation.Cellular StageChemicals released into the injured area during the vascular stage attract immune cells including neutrophils and macrophages which destroy pathogens and damaged tissues by phagocytosis. The complement system, a series of proteins found in the blood, also increases inflammation and phagocytosis as well as promoting other immune responses.Repair StageAs pathogens and dead or injured tissues are removed, the repair process is able to begin. This can happen in one of two ways. The damaged cells can be replaced with new cells of the same type, often with no sign of the original injury. However they are sometimes replaced with connective tissue which results in the formation of scars. Scars can occur both internally and externally to the body. Inflammatory MediatorsChemicals released during inflammation are known as inflammatory mediators. They have a number of different roles in the inflammatory process. You do not need a detailed knowledge of the chemicals at this stage of your studies, but it is useful to have a general understanding of the chemicals involved and what roles they play.OutcomesThe purpose of acute inflammation is to help the injured tissue to heal. Sometimes this is more successful than others. There are three main possible outcomes of acute inflammation:Healing – the injured tissue repairs to more or less its original state.Fibrosis – the injured tissue is replaced by fibrous connective tissue which forms scars.Continued inflammation – the healing process is incomplete, often due to continued aggravation, which in turn can lead to chronic inflammation.1.5.2CHRONIC INFLAMMATIONChronic inflammation has a slow onset and can persist for weeks, months or even years. The symptoms are generally the same as for acute inflammation but in a milder form.Acute inflammation can become chronic if:The body is unable to rid itself of the foreign body or pathogen that is causing the inflammation.The pathogen keeps re-entering the body.Other causes of chronic inflammation are:Persistent physical injury e.g. overuse injuries, particularly in athletes.Pathogens that can avoid or resist the body’s defence mechanisms.Pathogens that persist in damaged regions that cannot be reached by the body’s defences e.g. abscesses.Irritant foreign bodies that cannot be removed by enzymes or phagocytes e.g. deep splinters, grit in wounds.Hypersensitivity conditions e.g. asthma, hayfever.Auto-immune conditions e.g. rheumatoid arthritis.Other conditions with no known cause e.g. Crohn’s disease.Inflammation can be divided into acute and chronic inflammation.1.5.3HEALINGFollowing damage to tissues, there are three possible outcomes:Resolution – dead cells and other debris are removed by phagocytosis. The existing tissue is left undamaged in its original stage.Regeneration – tissue that has been lost is replaced in its original form.Repair – the lost tissue cannot regenerate and is replaced by fibrous connective tissue known as scar tissue. ResolutionThis occurs when there is little destruction of the original tissues. The infecting pathogen is destroyed or removed before it is able to inflict significant damage to the cells and tissues so repair is not required.RegenerationWhen cells and tissues are destroyed, it is sometimes possible to replace them with the same type of cell by proliferation. Some cells are more able to regenerate than others.Epithelial cells (skin) have a high ability to regenerate, as do red and white blood cells which are made in the bone marrow. These cells have a naturally high turnover so they are always being regenerated and replaced.Other cells are normally stable but they can be stimulated to regenerate following injury. These include the cells of the liver, kidneys and bones. Some cells are unable to regenerate and therefore any damage is permanent. These include cells of the brain and nervous system. Cells with no blood supply such as cartilage and ligaments are also unable to regenerate. RepairWhere damage is extensive or the cells have limited ability to regenerate it may not be possible for the body to repair itself with the original type of tissue. Simple structures are also easier to heal than complex ones. In these cases the body may repair itself with fibrous connective tissue which is easier to produce. This will lead to the formation of scars. Scars can form both internally and externally. LESSON 2 – CELLULAR PATHOLOGYCell Injury2.1.1Causes of Injury2.1.2Mechanisms of InjuryAdaptation of Cells2.2.1Atrophy2.2.2Hypertrophy2.2.3Hyperplasia2.2.4Dysplasia2.2.5Intracellular Accumulations2.2.6CalcificationCell Death2.3.1Apoptosis2.3.2NecrosisAging Theories2.4.1Stochastic Theories2.4.2Genetic Theories2.1CELL INJURYCell injury can result from many different causes and also affect the cells in a number of different ways. Depending on the type and extent of injury and the type of cell affected, the injury may be reversible and the cell can recover. Sometimes the damage is irreversible and cell death will occur. 2.1.1CAUSES OF INJURYThere are many potential causes of cell injury, which can be grouped into different categories:Physical agentsRadiationChemicalsBiological agentsNutritional imbalances Physical AgentsPhysical agents are things which can cause physical trauma to the body. These include:Mechanical forcesTemperature extremesElectrical injuriesMechanical ForcesMechanical injuries arise from the body impacting with another object – or the other way round. These can include cuts, split or torn tissues, fractured bones, broken blood vessels or interrupted blood flow. Temperature Extremes Both extreme cold and extreme heat can cause cell injury.Cold causes vasoconstriction which decreases blood flow and therefore nutrient and oxygen supply to the cells which will then become injured due to lack of oxygen. In extreme cold conditions the fluid inside the cells can freeze into ice crystals. This will rupture the cell membrane as ice takes up more space than water. Moderate heat causes damage to the blood vessels through excessive vasodilation, accelerates cell metabolism, inactivates some enzymes and damages the cell membrane. Intense heat can cause coagulation (clotting) of blood and also tissue proteins. Electrical InjuriesIn electrical injuries, the body acts as a conductor. The electrical current enters the body at one point and travels through the body before exiting at another point. Resistance to the electrical current causes heat – just like the element in your toaster or kettle when it gets hot. The heat in the toaster is created by resistance to an electrical current running through the element. That is why you should always unplug it before fishing your toast out with a metal knife. Heat is generated in exactly the same way when electricity passes through your body. The effects of the heat on your cells are exactly the same as those described above.Electricity passing through the body can also disrupt the electrical currents passing through nervous and cardiac tissue. Heart rhythm is controlled by electrical impulses from nodes in the heart as well as impulses received from the brainstem. When the heart enters fibrillation which is a state where it beats erratically, a doctor may use a machine called a defibrillator to momentarily stop the heart. The hope is that it will then restart with a normal rhythm. RadiationRadiation causes waves of energy. It is classified according to the frequency at which the waves occur. The higher the frequency, the higher risk of injury. Ionising RadiationThis is the highest frequency and therefore the most dangerous. It is higher than ultraviolet radiation. It causes swelling, injury to the organelles and nucleus and rupture of the cell membrane. This is the type of radiation which is used to kill cancer cells. Ultraviolet (UV) RadiationThis is the most common type of radiation and is produced by the sun’s rays. UV radiation causes sunburn. It also stimulates the production of melanin in the skin which protects against the harmful effects of UV radiation.UV radiation can lead to skin cancer, where the melanocytes (the cells which produce melanin) multiply abnormally. Although it is less common than some of the other skin cancers, it is the most dangerous because it has the highest likelihood of spreading to other parts of the body.Non-ionising RadiationThis includes infrared light, ultrasound, microwaves and lasers. It is lower frequency and less dangerous than the other forms of radiation. Unlike the other types of radiation, it is not strong enough to break the chemical bonds between molecules in the cells. Instead it just makes the atoms rotate and vibrate. Injuries from this type of radiation usually occur due to the increased temperature caused by the molecule vibration rather than the radiation itself. ChemicalsThere are many different chemicals which can cause injury to cells. These can include drugs, environmental pollutants and metals.DrugsDrugs include prescription and over-the-counter medicines as well as tobacco, alcohol and illicit drugs. Some drugs directly injure the cells, while others cause the production of metabolic products within the body which then cause injury. Another way in which drugs can affect the cells is by interfering with their ability to reproduce. This is why medical practitioners – including natural health practitioners – have to be very careful when prescribing anything to a pregnant woman. Environmental pollutantsThere are many toxic chemicals polluting both our air and water. Some of the most dangerous include pesticides and carbon monoxide. MetalsMetals can also cause damage to cells. Some, like iron or zinc, are beneficial in small quantities (although they can still cause damage in excess).Others, like lead or mercury, are toxic even in low doses. Lead is absorbed into the bone and can replace calcium. It also competes with the enzymes which make haemoglobin, the substance that transports oxygen round the body. Perhaps the most serious effect is that on the nervous system as it can destroy brain cells. Mercury is also toxic to the nervous system. The small amounts in dental fillings are not normally enough to cause harm, but if you are worried you can have your fillings replaced. There is more risk from excessive consumption of large fish like tuna. Biological AgentsBiological agents are pathogens such as viruses and bacteria. There are many different ways in which they can destroy cells. Viruses can enter the cells and interfere with the DNA while bacteria can interfere with the cell’s ability to produce energy or cause injury to the cell membrane.We will have a look at infectious diseases in a later lesson. Nutritional ImbalancesNutritional imbalances can take the form of either a lack or excess of nutrients. The body requires a wide variety of different nutrients within certain ranges. Too much or too little of any nutrient can lead to cell and tissue damage.Macronutrients are those we need in large quantities. They are fats, proteins and carbohydrates. Excessive consumption can lead to obesity, hypertension and all the associated diseases. On the other hand, not eating enough can lead to starvation and tissue breakdown. Micronutrients are vitamins and minerals. They are vital for normal cell function but again, many of them can cause injury if taken in excess. 2.1.2MECHANISMS OF INJURYThere are many different ways in which the agents described above can cause damage to the cells. Some, such as heat, cause direct damage to the cells. Others cause injury by interfering with metabolic processes and altering immune responses.Apart from direct injury, there are three many ways in which injury can occur:Free radicals – reactive chemicals which can start chain reactionsHypoxia – lack of oxygen to cells and tissuesCalcium imbalance – activates enzymes inappropriately Free RadicalsFree radicals are chemicals with a free electron in the molecular structure which causes them to be highly reactive and unstable. They react with proteins, lipids and carbohydrates in cells and tissues. This causes damage to the cell membrane, inactivates enzymes and damages DNA. They can also start chain reactions which create more free radicals. Some non-radicals such as hydrogen peroxide can also behave in a similar manner. Collectively, all these chemicals are known as random oxygen species (ROS).Antioxidants are a separate group of chemicals that help neutralise the ROS and counteract their damaging effects. There are many that can be found in the diet including vitamins A, C and E, zinc and selenium. HypoxiaHypoxia is a lack of oxygen to the cells and tissues. Oxygen is essential for the metabolic processes within the cells including the production of energy in the form of ATP. Some cells need more oxygen than others to perform their functions. The heart, brain and kidneys require large amounts of oxygen. Brain cells begin to die after just 4-6 minutes of oxygen starvation. If you come across someone who is not breathing it is vital to start resuscitation straight away. Don’t wait for the ambulance. Quick action could make the difference between life and death. Calcium ImbalanceCalcium acts as a messenger for many cell responses, including muscle contraction and release of glucose from glycogen. Normally calcium levels in the cells are very low. Ischaemia (lack of blood supply) and some toxins can cause an increase in calcium levels in the cells. The increased calcium levels can trigger the release of enzymes within the cell which can cause damage, including damage to the cell membrane. 2.2ADAPTATION OF CELLSCells change in response to the internal environment within the body just as well as the total body responds to changes in the external environment. As with everything, there are both benefits and disadvantages to the responses.2.2.1ATROPHYAtrophy is a decrease in size of a cell, tissue or organ. In the case of tissues and organs this can mean not only a decrease in the size of the cells but also the number of cells.The main reasons for atrophy occurring are:Disuse DenervationLack of endocrine stimulationInadequate nutritionLack of blood flowDisuseDisuse atrophy occurs mainly in skeletal muscles. This could be due to illness, injury or a change in lifestyle such as reducing exercise. Someone who is bedridden for a period of time will experience muscle atrophy. Astronauts also experience atrophy because the lack of gravity means that they are not doing resistance exercise. DenervationDenervation means a loss of nerve supply to an area. It often causes paralysis. The main cause of denervation is trauma such as an accident but it could also occur from nerve compression, for example a tumour pressing on a nerve. Endocrine StimulationSome tissues atrophy with the loss of endocrine (hormonal) stimulation. A good example of this is the menstrual cycle. The blood vessels supplying the endometrial lining of the uterus atrophy once a month when oestrogen and progesterone levels drop. This causes the lining to be shed during the menstrual period. NutritionWhen cells receive inadequate nutrition they will decrease their size and energy requirements in order to survive.Lack of carbohydrate intake can also cause atrophy of both adipose and muscle tissue in order to release energy. Blood SupplyWhen blood supply is low the cells do not receive adequate oxygen and nutrition so they decrease size and energy requirements to compensate. 2.2.2HYPERTROPHYHypertrophy is an increase in cell size and therefore an increase in the overall tissue mass. Hypertrophy can happen due to normal physiological reasons or pathological causes.Physiological reasons are those that normally happen, with no underlying disease. This mainly happens to skeletal muscle with exercise.Pathological hypertrophy happens where there is a disease condition. An example of this is hypertrophy of the heart muscles due to hypertension. The heart has to work harder than normal so the muscle thickens. When one kidney is removed, the other kidney can hypertrophy – that is, it becomes larger than normal – in order to compensate for the additional workload.Adipose cells will hypertrophy to increase fat stores when dietary intake of calories exceeds expenditure. 2.2.3HYPERPLASIAHyperplasia is an abnormal increase in number of cells. This occurs in tissues with cells that have a high rate of multiplication such as epithelial tissue. There are two types of hyperplasia – hormonal or compensatory.Hormonal hyperplasia occurs in breast enlargement during pensatory hyperplasia occurs in the formation of scar tissue in wound healing. 2.2.4 DYSPLASIADysplasia is the development within a tissue of cells that are irregular in size, shape and organisation. This is seen to a small degree in chronic inflammation.Dysplasia can sometimes be a pre-cursor to cancer, but it is not cancer at this stage because it is reversible. Often the tissues return to their original condition.The Pap smear used to detect risk of cervical cancer does this by detecting dysplasia of the cervix. 2.2.5 INTRACELLULAR ACCUMULATIONSIntracellular accumulation is the accumulation within the cells of substances that are not immediately used or eliminated. There are three groups of substances that can accumulate within the cells:Normal body substances – proteins, carbohydrates, lipids, bilirubin and melanin that are present in abnormally large amountsAbnormal body substances – arising from metabolic disturbances, often due to genetic disorders e.g. glycogen storage diseasesExogenous substances – substances from outside the body that accumulate within the cells e.g. toxins2.2.4 CALCIFICATIONCalcium is important to the function of cells but it is normally only present in very small amounts. Calcification is the build-up of abnormally large quantities of calcium within the cells which can then crystallise. There are two types of calcification:Dystrophic calcification occurs in dead or dying tissues. It is often seen in atherosclerosis (hardening of the arteries) or damaged heart valves.Metastatic calcification is found in normal tissues. It can occur from diseases which cause calcium loss from bones, bone cancer or vitamin D toxicity. 2.3CELL DEATHThe ultimate outcome of irreversible cell damage is cell death. There are two types of cell death:Apoptosis – programmed cell deathNecrosis – unregulated cell death2.3.1APOPTOSISApoptosis is a regulated, highly controlled process that selectively eliminates injured and aged cells in order to control regeneration of tissues. It is part of the normal process of growth and development. Apoptosis is involved in:Programmed destruction of cells due to age (e.g. red blood cells)Hormone induced cell death (e.g. menstrual period)Cell death caused by killer T cellsControl of cell proliferationInterference with the process of apoptosis can contribute to the development of cancer as the abnormal cells proliferate and are not killed off. 2.3.2NECROSISNecrosis is the unregulated death of cells in a living organ or tissue. In necrosis, the cell contents are destroyed by enzymes and the cell membrane is damaged causing it to rupture. Necrosis often interferes with the process of generating new cells and regenerating tissues. Gangrene occurs when a significant mass of tissue undergoes necrosis. There are two types of gangrene:Dry gangrene usually occurs due to a loss of blood supply. The area becomes dry and shrinks and changes colour to dark brown or black. It usually has slow progress.Wet gangrene usually occurs due to a bacterial infection. The area is cold, moist to touch, swollen and black in colour. It has a much faster rate of progress. 2.4AGEING THEORIESMany theories have been put forward as to the causes of ageing at a cellular level and organ level. They can be grouped into two broad categories:Stochastic theoriesGenetic theories2.4.1STOCHASTIC THEORIESStochastic theories propose that ageing is caused by random damage to molecules within the cells. There are three main theories:Somatic mutation theoryFree radical theoryWear and tear theorySomatic mutation theoryThe DNA in the cell undergoes constant change due to cellular processes and extrinsic substances which enter the cell. These changes lead to mutations in the DNA of the cell or defects in the DNA’s repair processes.Free radical theoryFree radicals are highly reactive chemicals which are created as the result of oxidative metabolism in the cells. They can cause chemical reactions within the cells which can damage the DNA, proteins, lipids and other structures within the cells. This leads to cell damage and ageing. Wear and tear theoryThis theory suggests that the damage to cells is cumulative over long periods of time. Eventually the damage becomes too great and the cell will die. 2.4.2GENETIC THEORIESThe genetic theory suggests that the lifespan of cells is programmed into our genes.The end of each chromosome in a strand of DNA is finished off with a telomere which stops the strand from fraying – a bit like the plastic on the end of a shoe lace.Each time the DNA is replicated to produce a new cell, the telomere gets a bit shorter. When the telomere gets very short, the cells stop replicating because any more would result in a complete loss of the telomere in which case the DNA would begin to unravel. Some genes are not directly involved in ageing but they can influence the lifespan of an individual. An example of this is the BRAC1 gene which is involved in breast cancer. Note that it is the breast cancer that leads to death, not the gene itself.LESSON 3 – NEOPLASIA AND CANCER3.1Neoplasia 3.2Malignancy3.3Metastasis3.4Types of Tumour3.5Causes and Risk Factors3.5.1Exogenous Factors3.5.2Endogenous Factors3.6Treatment3.1NEOPLASIAWhat is neoplasia?Neoplasia can be defined as:An abnormal and uncoordinated proliferation of cells, exceeding that which would be expected from normal tissue.That doesn’t necessarily mean that all neoplasms are dangerous. Some, like moles or keloid scars, may not look very nice but they are not actually doing us any harm.Neoplasms can be either benign or malignant. Benign neoplasms are relatively harmless. They grow slowly and do not migrate to other parts of the body. Malignant neoplasms are more dangerous these are the ones that grow and spread. When neoplasms become malignant they are referred to as cancer.A neoplasm that forms a solid mass or lump is known as a tumour. This distinguishes it from other types such as the blood-borne neoplasms like leukaemia. 3.2MALIGNANCYMalignant neoplasms are also known as cancer.There are two types of malignant neoplasms – solid tumours and haematological cancers. Tumours are solid growths or masses which initially stay in one place. Haematological cancers involve lymph or blood cells so travel freely round the body. A malignant neoplasm is one which has lost the ability to control both the rate of proliferation and the differentiation of the cells of which it is made. Proliferation is the rate at which the cells multiplyDifferentiation is how the cells determine what kind of cell they are going to be – how they differ from the cells around themWhen this happens, the cells grow rapidly and in a disorganised manner. Malignant tumours are not encapsulated, so it is easy for them to spread and invade the surrounding tissues where they destroy the normal cells. Bits of them can also break off and enter the blood or lymphatic systems and travel to other parts of the body. This is known as metastasis.3457575104140003.3METASTASISSometimes bits of solid tumours break off and travel round the body until they lodge somewhere and start a new tumour in a new location. There are three main ways in which the tumour cells can migrate through the body:Blood streamLymphatic systemBody cavitiesBlood stream One feature of tumours is that they are able to develop their own blood supply to feed them with nutrients – this is why they are able to grow so fast. When cancer cells break away from the original tumour they can enter the venous blood vessels and are then transported round the body in the blood. Veins from the gastrointestinal tract, pancreas and spleen enter the liver before the blood is returned to the general circulation so the liver is a common site for metastases from gastrointestinal or pancreatic cancers. Lymphatic systemCancer cells often metastasise through the lymphatic system. With many types of cancer, the first sign of metastasis is finding tumour cells lodged in the lymph nodes that receive drainage from that area.All lymphatic fluid is filtered through the lymph nodes before it is returned to the blood circulation. Tumour cells are filtered out and trapped in the lymph nodes. Most of them will die here but some may survive and grow and many then spread to other lymph nodes.Body cavitiesThe internal body cavities are filled with fluid to provide shock absorption and reduce friction to the internal organs. Cancer cells from tumours in the internal organs can enter the body cavities and will then lodge in surrounding tissues. 3.4TYPES OF TUMOURTumours are named according to whether they are benign or malignant and the tissue or organ in which they are found. Solid tumours have names ending in –oma. Most malignant tumours are called either carcinoma or sarcoma. The main exception to this rule is cancers of the blood which are called leukaemia.If you know the terminology for the different organ and tissue types, you can often work out what is what.Tissue TypeBenign TumourMalignant TumourEpithelial TissueSurface epitheliumGlandsPapillomaAdenomaCarcinoma Connective TissueFibrous tissueAdipose tissueCartilageBoneBlood vesselsLymph vesselsLymph nodesFibromaLipomaChondromaOsteomaHemangiomaLymphangiomaFibrosarcomaLiposarcomaChondrosarcomaOsteosarcomaHemangiosarcomaLymphosarcomaLymphomaMuscle TissueMuscleMyomaMyosarcomaNervous TissueNervesNeuromaNeuroblastomaBloodWhite blood cellsPlasma cellsLeukaemiaMyelomaAs we discussed before, tumours can also be divided into benign and malignant depending on how fast they grow and how easily they spread to other parts of the body. 3.5CAUSES AND RISK FACTORSThe process by which cancer is created in the body is known as carcinogenesis. There are many different reasons why cancers can develop in the body. As the rate of death from cancer is increasing it is more important than ever to understand how and why it can occur.Of course, a large part of the reason for the increase is that we are now less likely to die from other causes. Death from contagious diseases is now very unlikely due to comprehensive vaccination programs and improvements in treatments. Similarly, there are breakthroughs in treatments for cardiac disease and other conditions. The sad truth is that we will all die of something eventually, and since the likelihood of being hit by a bus is not that high, chances are it will be cancer that gets us in the end until the progress in prevention and treatment becomes so great that something else takes over. The factors that influence whether or not we get cancer can be divided into:Exogenous factors – those originating outside the bodyEndogenous factors – those originating inside the body3.5.1EXOGENOUS FACTORSExogenous factors are those arising from outside the body. They can include chemical and environmental agents. These are collectively known as carcinogens. Some common carcinogens are:Cigarette smokeUltraviolet lightRadiation AsbestosSome viruses (e.g. HPV)Some insecticides Burnt foodsAlcohol 3.5.2ENDOGENOUS FACTORSEndogenous factors are those that arise from within the body. There are a number of factors that can increase the risk of developing cancer:Genetics (e.g. BRCA breast cancer gene, Down’s syndrome)ImmunodeficiencyPre-existing benign neoplasms (e.g. moles)Hormones (e.g. oestrogen, testosterone)AgeObesity3.6TREATMENTAs our understanding of how cancers develop improves, so do the treatment options available. The aims of cancer treatment are:Eliminate the cancerSlow the progressPalliative care – alleviate sufferingSadly, not all cancers can be treated successfully – especially those that have metastasised. In these cases, doctors will do what they can to slow the progress and give the person as much time as possible with family and loved ones.Palliative care is the act of caring for people in the terminal stages of an illness who will not recover. Palliative care aims to make their last days as comfortable as possible.Treatment options to reduce or eliminate cancer in the body include:SurgeryChemotherapyRadiation therapyHormone therapyStem cell treatmentSurgerySurgery is the oldest form of cancer treatment. It can be used to remove localised cancers. Surgery is also used in diagnosis and assessing the progress of cancer by taking biopsies. Recent developments in surgical techniques include cryosurgery (freezing), chemosurgery (using chemicals to destroy tumour), laser surgery and laparoscopic surgery.ChemotherapyChemotherapy drugs act by inhibiting DNA production within the cancer cells and stopping them from replicating. Unfortunately there are some serious and unpleasant side effects from chemotherapy drugs.inhibit production of red and white blood cells by bone marrow leading to:anaemia (lack of red blood cells)compromised immune system (lack of white blood cells)cause loss of appetite, nausea and vomitingcause alopecia (hair loss)Radiation therapyRadiation therapy uses high frequency radiation to target and kill cancer cells which are more susceptible to the damaging effects of radiation than normal cells.The down side is that all cells are susceptible to damage from the radiation. Recent advances in using ultrasound to pinpoint the target site and guide the radiation mean that the risk of collateral damage is reduced.Hormone therapySome cancers such as breast cancer and prostate cancer depend on the presence of certain hormones to be able to grow. The aim of hormone-based cancer treatments is to deprive the cancers of the hormones that they need to grow. Stem cell treatmentThis treatment is used for the treatment of leukaemia. Stem cells are harvested either from the blood stream or directly from the bone marrow and then stored.Depending on the type of leukaemia, the harvested stem cells can be either autologous (from the patient themselves) or allogenic (from a donor).The patient then undergoes an intense treatment of chemotherapy and/or radiotherapy to kill off any cancer cells in the body. This treatment also has the effect of killing off all the cells in the bone marrow. The stored bone marrow cells are then returned to the patient about a day after the chemotherapy is finished.Using stem cells from a donor is very risky because of the risk of rejection which can lead to multiple organ failure in the patient so it is only used as a last resort. LESSON 4 – HOMEOSTASIS AND FLUID BALANCE4.1Fluid and Electrolyte Balance4.1.1Dehydration4.1.2Electrolytes4.1.3Oedema4.2Body Temperature4.2.1 Hypothermia 4.2.2Hyperthermia4.2.3Fever4.3Activity and Fatigue4.3.1Exercise Tolerance4.3.2Fatigue4.3.3Immobility4.1FLUID AND ELECTROLYTE BALANCEApproximately 60% of the body is made up of water, of which about 2/3 is inside the cells and the other 1/3 is in the spaces between the cells or in the blood plasma. The actual amount can vary quite a lot. The amount of fluid decreases substantially with age while men have more fluid than women. Muscle cells contain more water than adipose cells, so levels of body fat also influence the amount of water. Body fluids carry gases, nutrients and waste products around the body. Regardless of age, all healthy people require about 100ml of water per 100 calories (400 kilojoules) metabolised. That means that the average person who expends about 2000 calories per day needs to consume approximately 2 litres of water. This includes the water in food as well as drinks. Many fruits and vegetables have a high water content. Most water is lost through the kidneys as urine with smaller amounts lost through the intestines, lungs and skin. The minimum amount that the kidneys need to pass each day in order to rid the body of metabolic wastes is about 500ml. 4.1.1DEHYDRATIONDehydration occurs when body fluids fall below the level required to maintain blood volume and extracellular fluid and therefore provide adequate fluid, oxygen and nutrients to the cells. The severity is usually measured according to changes in body weight.Mild deficit – loss of 2% of body weightModerate deficit – loss of 5% of body weightSevere deficit – loss of 8% of body weight4.1.2ELECTROLYTESElectrolytes are the ions of various minerals that are found within the fluid and cells of the body. If you have studied chemistry, you will know that the ion of a substance has either a positive or negative charge – hence the name. There are a number of electrolytes that are important to the normal functioning of cells and tissues within the body. While they are only required in small amounts, an imbalance of any of these can cause problems. Imbalances can occur due to:Inadequate dietary intakeExcess loss through urineExcess loss through sweatVomiting or diarrhoeaExcess water intake without electrolyte intakeThyroid or adrenal problemsLiver or kidney diseaseAbsorption issues in small intestineDrugs and medications048196500Here are some of the key electrolytes and the effects that can result from having either too much or too little:072390004.1.3OEDEMAOedema is defined as an excess accumulation of fluid in the body tissues it may be:Localised – as seen in injury or inflammationGeneralised – throughout the body, various causesLocalised OedemaLocalised oedema can result from injury such as a wound, burn or muscle sprain. It is part of the inflammatory process that helps with tissue healing. Look in the lesson above if you want to jog your memory on inflammation.Localised oedema can also occur as part of an allergic inflammatory response. Generalised OedemaGeneralised oedema is widespread through an extensive area of the body. It can result from electrolyte imbalance (see above), hormones, kidney failure, heart failure or liver failure.Generalised oedema is significant to you as a practitioner because it can be an indication of a serious underlying medical condition. Puffy ankles could just mean that the client has spent too long on their feet or it could be an indication of heart disease. It’s important to find out which before you treat them. Vigorous massage on a person with cardiac disease could result in too much fluid being pushed back into the circulatory system which could overload the heart. LymphoedemaLymphoedema occurs when there is damage to the lymphatic system which impairs the ability to drain fluid away from an area of the body. A common example of this is in women who have had lymph nodes removed from their armpit following breast cancer. The resulting scar tissue means that the lymphatic fluid cannot drain from the affected arm and so they get swelling. 4.2BODY TEMPERATURENormal body temperature is usually around 37oC but can be around 0.5oC either side of this. Maintaining body temperature is important because a temperature that is either too high or too low can affect ability of the cells to perform their normal functions. In extreme cases cell injury or death can occur. Body temperature is the result of a balance between heat gain and heat loss by the body. Most of the heat gained is the result of metabolic processes occurring mainly in the skeletal muscles and internal organs. Excess heat is then transferred from the core to the surface via the blood and is lost into the atmosphere through the skin.The hypothalamus controls the body temperature. When the body is too hot, it will try to reduce heat by inducing sweating. The water evaporation from the skin causes cooling. When the body is cold it will try to conserve heat by reducing blood flow to the surface and extremities and shivering to generate heat in the muscles. 4.2.1HYPOTHERMIAHypothermia is an abnormally low body temperature. It is defined as a temperature below 35oC. It is a change that occurs without a change in the regulatory temperature set-point by the hypothalamus. Hypothermia is usually due to prolonged exposure to cold environments. Hypothermia is more common in small children and the elderly. Children have a larger ratio of surface area to body mass so they lose more heat. Elderly people have slower metabolism and are less active so they generate less heat in their muscles. 4.2.2HYPERTHERMIAHypothermia is an abnormally high body temperature. It is defined as a temperature above 39oC. It is a change that occurs without a change in the regulatory temperature set-point by the hypothalamus. Hyperthermia occurs when the body is overwhelmed by excessive metabolic heat production, impaired heat loss or high environmental temperatures. 4.2.3FEVERFever is an increase in body temperature due to an increase in the regulatory temperature set-point by the hypothalamus. This is different to hyperthermia which is due to external factors.Fevers caused by the hypothalamus are usually between 39oC – 41oC. Fevers below 40oC are not generally considered to be harmful to the body, but fevers in young children can sometimes cause convulsions which can be harmful to the brain and nervous system if they go on for a long period.Substances which cause fever are called pyrogens.The exact purpose of fever is unknown but it is thought to be because some bacteria and viruses are less able to survive in a hot environment. 4.3ACTIVITY AND FATIGUEActivity can be defined as expending energy for a purpose. In this section we will be looking at physical activity which includes exercise, but it also includes incidental activity – moving around during our daily activities.Our ability to exercise, and indeed to carry out everyday physical activities is influenced by general health, cardiovascular fitness, muscle strength, flexibility and motivation. 4.3.1EXERCISE TOLERANCEExercise tolerance is a person’s ability to tolerate exercise and perform physical tasks. It can be influenced by both physical and mental factors. Intolerance is the inability to complete activities due to lack of physical or psychological energy. There are a number of ways in which exercise tolerance can be measured. The most common is to use a subjective scale, asking the person how tired they feel or how difficult they find the task. Another way of measuring tolerance is to monitor cardiac output during exercise. This is usually done on a treadmill and is known as stress testing because it tests how hard the person is able to push themselves before reaching the maximum safe heart rate.One good indicator is the maximal oxygen consumption (VO2max) which is the maximum amount of oxygen a person is able to use in a minute. The higher the result the more activity they are able to tolerate.4.3.2FATIGUEFatigue is a state of mental or physical tiredness following a period of activity. It can be either acute or chronic.Acute FatigueAcute fatigue has a rapid onset and limited duration following a period of intense activity. It will resolve either when the activity ceases or shortly afterwards. The level and duration of activity before acute fatigue results will depend on the muscle strength and cardiovascular fitness of the individual.Chronic FatigueChronic fatigue has a slow onset and lasts for a long period of time. The level of fatigue is higher than would be expected compared to the level of activity and does not resolve when activity is ceased. Chronic fatigue can be caused by an underlying medical condition such as heart disease or obesity, viral infection or depression. Chronic Fatigue Syndrome is defined as chronic fatigue that lasts for 6 months or more, is not relieved by rest and is accompanied by other symptoms. There is no established cause but it is often preceded by viral symptoms and has been linked to Epstein-Barr virus.Treatment involves management of symptoms and encouraging the patient to continue normal activities as much as possible. 4.3.3IMMOBILITYImmobility and bed rest cause enforced inactivity. Immobility may result from an injury that requires immobilisation and stabilisation to facilitate healing or it may result from a medical condition that limits physical ability.Bed rest is often prescribed as a treatment for persons recovering from serious illness.The complications that can occur from immobility and bed rest are:Atrophy of skeletal musclesDeconditioning of cardiac muscleRedistribution of blood volume from periphery to coreOsteoporosisPneumoniaUrinary retentionConstipation DepressionLESSON 5 – INFECTIOUS DISEASES5.1Pathogens 5.2Spread of Infection5.3Treatments5.4Vaccinations5.4.1Immunisation and Vaccination5.4.2National Immunisation Program5.4.3Commonly Vaccinated Diseases5.1PATHOGENSPathogens are living organisms that can invade the body and cause disease. The main types of pathogen are:BacteriaVirusesFungiParasitesOthers We will look at specific diseases caused by all these different types of organisms as we work our way through this course. BacteriaBacteria are single-celled organisms which do not have a distinct nucleus. They are able to reproduce by simply dividing the cell. Bacteria are everywhere – in the soil, water and air. They also live in plants, animals and humans. Many are not harmful and can even be beneficial like the bacteria that live in your gut and help with digestion. Think of all those adverts for probiotics that are always on television. Probiotics help develop a colony of “good bacteria” in the intestines. Some bacteria however are harmful. They do not usually attack the body cells themselves but they can release powerful toxins which damage cells. VirusesViruses are the smallest type of pathogen. They do not have an organised cell structure and consist of just a nucleus of DNA surrounded by a protein shell. Viruses are so small that they cannot be trapped by filters or seen under a normal microscope.Viruses are responsible for many common diseases including cold, influenza, chicken pox, measles, mumps, polio and rabies.Viruses do not respond to antibiotic treatment but many of them can be prevented by vaccination. FungiFungi are members of the plant kingdom. They lack chlorophyll which is what makes the green colour in most plants. They come in many colours, shapes and sizes including edible mushrooms and poisonous toadstools. They also include yeast and mould. The antibiotic penicillin was originally developed from mould.Many species of fungi are capable of living as parasites on either plants or animals. The ones that infect humans are of microscopic size and can cause skin infections. Usually these infections are self-limiting – that is, they will only survive for a certain length of time before they resolve themselves.ParasitesStrictly speaking, any pathogen is a parasite because it lives off its host. However for this purpose we refer to members of the animal kingdom which can infect and cause disease in other animals. There are three main classes which infect humans:Protozoa – single celled animals that can cause diseases like malaria or dysenteryHelminths – also known as worms, mainly found in the digestive tract but can also infect other organs including the liver and brainEctoparasites – live on the outside of the body like lice and ticksOthersSmaller classes of parasites cause a range of diseases including some tropical fevers and some sexually transmitted diseases including chlamydia.5.2SPREAD OF INFECTIONSome diseases can pass more quickly through the population than others. Incidence is the rate at which new cases develop within a population over a given period of time. Prevalence is the number of people within that population that are infected at the same time. Diseases can be divided according to their prevalence:Endemic diseases are limited to a particular geographical area and are stable in terms of prevalence and incidence rates – they are not increasing.Epidemic diseases experience a sudden increase above the normal levels of incidence and prevalence but still within the normal geographical area.Pandemic diseases spread beyond international borders and have the potential to become global.There are number of ways in which pathogens can enter the body. The main ways are:PenetrationDirect contactIngestionInhalationPenetrationPathogens enter the body through a break in the skin or membranes. This could be a cut, graze, burn or ulcer. Some diseases like chicken pox can cause open lesions on the skin. Operating theatres are kept sterile and strict hygiene procedures are followed because surgical wounds present an easy opportunity for pathogens to enter the body.Direct ContactSome pathogens can be transmitted directly from exposed infected tissues to intact skin or membranes. Sexually transmitted diseases are often transmitted in this way. It is also possible to pick up diseases from touching surfaces that have pathogens on them. It is easy to pick up plantar warts (verrucae) at the swimming pool. The virus that causes the wart can survive on the tiled floor surrounding the pool and then transmits to anyone that steps on it. IngestionIngestion means taking in the pathogens through the mouth and digestive system. This is a very efficient way for pathogens to enter the body and many bacteria, viruses and parasites will enter in this way.In order to infect a person by ingestion the pathogen must be able to survive in the highly acidic environment of the stomach. InhalationA number of pathogens can enter the body via the respiratory tract, mainly bacteria and viruses.When thinking of acquiring infection by inhalation we automatically think of respiratory infections like pneumonia, influenza or tuberculosis. But many other viruses can also infect the body in this way including measles and chicken pox. 5.3TREATMENTSDifferent types of pathogens require different types of treatment. The three main types of treatment are:Anti-microbial agents – medications that will directly kill the pathogensImmunotherapy – boosting the patient’s immune systemSurgery – removing infected tissuesAnti-Microbial AgentsThere are a range of anti-microbial agents available including antibacterial, antiviral, antifungal and anti-parasitic agents.Antibacterial AgentsAntibacterial agents are normally known as antibiotics. Most are produced from other bacteria or fungi. Many antibiotics have side effects including allergic reactions and gastrointestinal upset.Antibiotics are only effective against bacteria and should not be given for anything else. They do not work against viruses like the common cold. Once a patient has started a course of antibiotics, they should always finish it. Failure to follow these guidelines has caused a rise in the number of antibiotic resistant bacteria which cannot easily be treated. Antiviral AgentsUntil recently there have been very few effective antiviral treatments but following the rise of AIDS in the 1980s research was put into developing antiviral medications.Most antiviral agents are aimed at the treatment of HIV and AIDS and work by inhibiting the virus’s ability to reproduce. More recently a new class of antiviral drugs has been developed to help fight influenza-type viruses.Nevertheless, the standard treatment for most viruses remains to support the immune system while allowing the infection to run its course.Antifungal AgentsMost antifungal agents work by breaking the cell membrane. Most are applied topically as the majority of fungal infections are on the skin but there are also some oral medications which should only be used when topical medications do not work due to their effect on the liver. Anti-Parasitic AgentsAnti-parasitic agents are as diverse as the parasites themselves. There are economic factors restricting the development of anti-parasitic agents as many parasitic infections occur mainly in developing countries.There is concern about continued effectiveness as some parasites become resistant to existing treatments for example some strains of malaria. ImmunotherapyImmunotherapy involves stimulating the body’s own immune system to respond to the pathogen so that the spread of the pathogen is limited or reversed. This can include immunotherapy after infection has taken place or immunisation to prevent the pathogen from taking hold in the first place.SurgerySurgery is considered a last resort. It is used when the infection cannot be controlled by other methods. Removal of the affected body part by surgery can prevent spread of the pathogen to the rest of the body.5.4VACCINATIONMany infectious diseases, especially bacteria and viruses, can be very serious or even fatal. Even diseases that we may not think of as particularly harmful – such as measles or whooping cough – can be fatal in vulnerable people. Fortunately, the incidence of many of these diseases has significantly declined and some have been eradicated. A lot of this is thanks to vaccinations. As more people are vaccinated, the disease is not able to spread and infect new victims so it becomes less common. The down side of this is that, as these diseases become less common within society, people are becoming complacent about the need for vaccines. This is leading to an increase in some common diseases with young children in Australia being hospitalised and even dying every year from diseases that could easily be prevented.5.4.1IMMUNISATION AND VACCINATIONMost people use the words immunisation and vaccination interchangeably but there is a difference. Vaccination – the act of receiving the vaccine, usually by injectionImmunisation – acquiring immunity against a disease as a result of having received a vaccine.So how do vaccines work? Usually they are administered by injection. There are several different types of vaccine. They can contain:A small amount of a live but weakened virusA small amount of a dead bacteria or virusA small amount of a modified toxin produced by a bacteriaAdministering the vaccine allows the body to develop antibodies to guard against future infection but without the serious symptoms which would normally accompany infection. Immunisation usually takes 1-2 weeks to take effect after the vaccination is administered. The length of time that the person remains immunised can vary depending on the disease. Some can last up to thirty years. Others, like the influenza vaccine, need to be repeated more often because the disease mutates so the vaccine is no longer effective. All vaccines in Australia are thoroughly tested for safety and side effects before they are approved for use by the Therapeutic Goods Administration (TGA). Some patients may get mild side-effects from the vaccination after it has been received. These may range from a low grade fever to mild symptoms of the disease itself. Severe reactions are very rare. There is no evidence that vaccinations cause autism or ADHD, in fact most scientific studies have proved quite the opposite. Many vaccines are given in childhood to prevent diseases like measles, chicken pox, diphtheria or whooping cough which were once common in our society. Although these diseases are often thought of as mild, they can be severe resulting in hospitalisation and sometimes even death. That is not a risk that anyone should take.Other vaccines are given to people travelling to foreign countries which have diseases not naturally occurring in Australia. These are known as travel vaccines. 5.4.2NATIONAL IMMUNISATION PROGRAMThe National Immunisation Program is a national government initiative to increase immunisation levels in Australia. There are 16 vaccines included on the register. The National Immunisation Program Schedule lists the vaccines covered by the Program and the ages at which they should be given.Vaccines included in the program are covered under Medicare when given at the ages listed in the Program.Child ProgramsBirthVaccine2 monthsHepatitis B, diphtheria, tetanus, whooping cough, Hib, polioPneumococcalRotavirus 4 monthsHepatitis B, diphtheria, tetanus, whooping cough, Hib, polioPneumococcalRotavirus6 monthsHepatitis B, diphtheria, tetanus, whooping cough, Hib, polioPneumococcalRotavirus12 monthsHib and meningococcal C18 monthsMeasles, mumps, rubella, chicken pox4 yearsDiphtheria, tetanus, whooping cough, polioMeasles, mumps, rubella, chicken pox (if not given at 18 months)School Programs10-15 yearsHepatitis BChicken poxHuman papillomavirus (HPV)Diphtheria, tetanus and whooping coughAt Risk Groups6 months and overInfluenza (medical conditions causing risk of serious complication)12 monthsPneumococcal (medically at risk)12-18 monthsPneumococcal (Aboriginal and Torres Strait children in high risk areas)12-24 monthsHepatitis A (Aboriginal and Torres Strait children in high risk areas)4 yearsPneumococcal (medically at risk)15 years and overInfluenza (Aboriginal and Torres Strait)Pneumococcal (Aboriginal and Torres Strait medically at risk)50 years and overPneumococcal (Aboriginal and Torres Strait children)Pregnant womenInfluenza65 years and overInfluenzaPneumococcal 5.4.3COMMONLY VACCINATED DISEASESThe schedule above lists the diseases for which vaccinations are usually given. Many of these diseases are now rare in Australian society due to immunisation which means that the disease is less able to spread however the trend towards non-vaccination means that they are now on the increase. Many of these diseases can be mild but can also have very serious consequences. The following table lists the main diseases covered under the National Immunisation Program and their effects on the body. 013081000LESSON 6 – MUSCULOSKELETAL DISORDERS6.1Trauma Related Injuries6.1.1Fractures6.1.2Dislocations6.1.3Strains and Sprains6.1.4Whiplash6.2Skeletal and Spinal Conditions6.2.1Osteoporosis6.2.2Scoliosis6.2.3Herniated Disc6.2.4Sciatica6.2.5Ankylosing Spondylitis6.3Joint Conditions6.3.1Osteoarthritis6.3.2Rheumatoid Arthritis 6.3.3Gout6.3.4Bursitis6.3.5Frozen Shoulder6.4Muscle and Connective Tissue Disorders6.4.1Cramps and Spasms6.4.2Tendinitis6.4.3Piriformis Syndrome6.4.4Iliotibial Band Syndrome6.4.5Shin Splints6.4.6Plantar Fasciitis6.4.7Tennis Elbow6.4.8Carpal Tunnel Syndrome6.4.9 Fibromyalgia6.1TRAUMA INJURIESWe all have accidents from time to time and those accidents often result in injury. Hopefully you have not had any serious injury yourself but let’s have a look at what kind of injuries can occur. 6.1.1FRACTURESA fracture is a broken bone. Fractures can be classed as simple or compound depending on whether the bone stays in position or moves. They can also be classed as open or closed depending on whether or not they break the skin. Fractures can partially or fully break the bone. There are many different forms that a fracture can take depending on how they occur. Some important types of fracture are:Greenstick fracture – does not go all the way through the bone. Usually happens in children. Their bones are more flexible and can bend slightly resulting in a partial minuted fracture – the bone is shattered into several pieces usually as the result of a heavy blow.Spiral fracture – caused by twisting of the bone.Stress fracture – small, often microscopic fractures caused by repeated stress or impact. Often occur in the foot.-2381252921000012604752240280Stress Fracture020000Stress Fracture14033517462500 Osteoporosis (low bone density) increases the risk of fractures.The elderly are more prone to fractures because their bones are less dense. They are also more likely to fall over.6.1.2DISLOCATIONSA dislocation occurs when two bones in a joint are displaced so that they no longer meet together and the joint is unable to operate. A subluxation occurs when the bones are only partially displaced.Some joints are more prone to dislocation than others depending on their structure. The shoulder is particularly susceptible. People with hyper-flexible joints are more prone to dislocations because the muscles and ligaments are holding the joints less tightly in place.Sometimes the dislocated bone will return to position on its own but sometimes needs to be put back in place by a medical professional. This should only ever be done by a suitably qualified professional because it is possible to trap a nerve or blood vessel.6.1.3STRAINS AND SPRAINSA strain is an injury to a muscle or tendon. A sprain is an injury to a ligament.Strains and sprains often occur from sudden trauma like a fall or accident but they can also be the result of accumulated low level trauma as in high levels of exercise over a long period of time. Strains and sprains can be divided into 3 grades depending on the level of injury:Grade 1 – fibres damaged up to 25% of total thickness of the muscle, tendon or ligament. 5-14 days healing time.Grade 2 – between 25% - 75% of total thickness damaged. 14-30 days healing time.Grade 3 – over 75% of total thickness of the tissue, up to and including 100% complete rupture. 2-12 months healing time.In severe cases, surgery may be required to fix the injury. Ligaments in particular are very slow to heal because they have little blood supply and are more likely to require surgical intervention.6.1.4WHIPLASHWhiplash is a collective term given to injuries sustained from a sudden uncontrolled movement of the neck and cervical spine. This can include injuries to muscles, ligaments, vertebrae and discs. It often occurs as the result of a car crash. Symptoms include neck pain, stiffness and headaches.Whiplash injuries should always be assessed by a doctor as there may be spinal injury which could cause long term nerve damage if untreated. 6.2SKELETAL AND SPINAL CONDITIONSThe skeletal system provides the structure and support for the body. You will have studied the skeleton as part of your anatomy and physiology studies. 6.2.1OSTEOPOROSISYou may well have heard of osteoporosis. It is a condition which is characterised by a loss of bone density. So how does this occur?There is a constant turnover of bone tissue in a process called remodelling. Cells called osteoclasts resorb the old bone material while cells called osteoblasts create new bone. Ideally these two processes should happen at the same rate in order to maintain bone density.In children, bone material is created faster than it is absorbed which is important because it allows them to grow and become stronger. We reach peak bone density in early adulthood and slowly lose density as we get older and the rate of bone loss begins to exceed the rate of bone formation. Osteoporosis is a condition where the bone density is significantly reduced due to an imbalance between the rate of bone resorption and bone formation. The result is that the bone becomes brittle and there is an increased risk of fractures.The formation of bone material requires lots of calcium. If there is not enough calcium available or if it is required for other purposes then this can affect bone density. Vitamin D is also required to convert calcium into bone material. Women are more at risk of osteoporosis than men because they have lower bone density to start with and changes in hormone levels after menopause inhibit the absorption of calcium into bones. Exercise also affects bone density, with weight bearing exercise essential to maintaining good bone density. Osteoporosis is usually diagnosed through a bone scan. It is a preventable condition in most cases but it is difficult to reverse once it has already occurred so prevention is very important through maintaining a healthy calcium rich diet and exercise. 6.2.2SCOLIOSISScoliosis is a lateral (sideways) deviation of the spine. It can be either congenital or acquired. Scoliosis can occur either due to a structural deviation of the spine itself or due to the muscles on either side of it pulling unevenly and therefore creating a curve. Uneven leg length can also create a scoliosis as the spine compensates for the difference in height between the two hips. Scoliosis is best treated in childhood as the spine and muscles are still growing. Treatment can consist of exercises, brace, cast or surgery depending on the severity of the curvature. 322897577470006.2.3HERNIATED DISCBetween each of the vertebrae in the spine is an intervertebral disc which provides cushioning and shock absorption to the spine. It is comprised of an outer casing of fibrous cartilage with an inner core of soft, gelatinous material. Sometimes the discs can become injured. Initially they may become compressed and create a bulge. As this increases the outer case of the disc can lose integrity and the inner material protrudes through to the outside. Depending on the direction of the bulge or protrusion there may be no symptoms but if it pushes on a nerve or the spinal cord it can cause considerable pain. It can also create muscle weakness and numbness. The part of the body affected will depend on exactly where the injured disc is located and therefore which of the peripheral nerves is affected. 6.2.4SCIATICAThe sciatic nerves are derived from the spinal nerves which exit between vertebrae L4 and S3. They run down the posterior of each leg. A disc protrusion at this level can press on the sciatic nerve causing pain in the back of the leg, numbness or weakness. Pain radiating down the leg from the sciatic nerve is known as sciatica. It should be noted that sciatica is not always due to disc protrusion. The nerve also runs through the centre of the piriformis muscle in the buttocks. This muscle can also press on the nerve when it becomes tight and produce the same symptoms.6.2.5ANKYLOSING SPONDYLITIS Ankylosing spondylitis (ankylos = stiff, spond = spine, itis = inflammation) is an inflammatory condition similar to rheumatoid arthritis that affects the joints of the spine. It usually starts at the sacrum and spreads up through the lumbar spine. Symptoms usually start as lower back pain and it can be misdiagnosed as a herniated disc. As it develops the pain and stiffness moves higher and will also spread into the hips. It is usually worst in the mornings and improves as the spine loosens up with movement. The main complications are fusion of the spinal joints and breathing difficulties as it becomes difficult to expand the rib cage.Treatment is limited to managing the symptoms through anti-inflammatory medications and exercises to improve strength and flexibility. 6.3JOINT CONDITIONSThe joints between our bones are what allow us to move. You will have learned about the different kinds of joints in anatomy and physiology. Now it is time to learn about some of the common conditions that can affect them. 6.3.1OSTEOARTHRITIS30861008382000The ends of our bones are covered with cartilage which protects the bone, provides shock absorption and provides a smooth surface to reduce friction on movement.Osteoarthritis is a degenerative condition where the cartilage gets worn away over time. It loses its smooth surface and becomes rough which causes friction on movement. This in turn increases the rate of wear and tear until eventually the cartilage is completely worn through.As the bone is irritated it reacts by trying to replace the cartilage by thickening. The bone is not smooth like the cartilage and the build-up of bone tissue restricts movement. It also creates pain on movement. 6.3.2RHEUMATOID ARTHRITISRheumatoid arthritis (RA) is an autoimmune condition in which the body’s immune system attacks the synovial membranes of the joint capsules causing inflammation. RA is usually found in the joints of the hands and feet but can be found in any joints of the body. It is different from other forms of arthritis in that it can sometimes affects parts of the body other than the joints.Most people with RA have a substance called rheumatoid factor in their blood. This is used as a diagnostic method but not all people with RA have rheumatoid factor while some people with rheumatoid factor will not develop symptoms of the disease. Women are 2-3 times more likely to develop RA than men. The main symptoms of RA are those of inflammation. Sufferers can also develop nodules – small bumps of connective tissue – around the affected joints. Over time the inflammation breaks down the synovial membrane causing fibrosis – the development of scar tissue. Destruction of the joint can lead to subluxation – partial dislocation of the joints. Swelling in the synovial capsule causes stretching of the synovium and the ligaments. This leads to muscle and tendon imbalances which in turn lead to joint deformities.Movement is restricted initially due to pain in the joints but later due to fibrosis. 6.3.3GOUTGout is an inflammatory joint condition caused by a build-up of uric acid crystals. 357187512065000Uric acid is a natural metabolic by-product that is formed when we digest certain proteins containing purine. Gout is a result of hyperuricaemia – a condition where the amount of uric acid produced exceeds the amount that can be cleared by the kidneys. This can be due to excessive production or poor kidney function. Over 90% of gout sufferers are men over the age of 40. Risk factors include high purine diet, obesity, alcohol consumption and high blood pressure. There is also thought to be a genetic factor. Signs and symptoms are intense, localised inflammation. It is found mostly in the toes which is thought to be due to gravity. The affected joint becomes bright red, very swollen and extremely painful to touch. Each episode lasts a few days to a few weeks. Initial attacks can be up to a year apart but get closer together other time. A potential complication of hyperuraemia is kidney stones which are also formed from uric acid crystals. Kidney stones can impair kidney function which means the kidneys have less ability to clear uric acid thus exacerbating the condition. Treatment of the acute condition is by anti-inflammatories. After this the treatment is aimed at preventing future attacks. Medications can inhibit the production of uric acid but the best method for preventing gout is lifestyle changes including a low purine diet. 3571875233680006.3.4BURSITISA bursa a fluid filled sac found at points of friction, mostly where tendons or muscles move over bone. Normally there is only a small amount of fluid in the bursa but if it is irritated or injured it may become inflamed and the amount of fluid increases. A bursitis usually occurs from repetitive stress so it is a common injury found with endurance sports. It can also accompany other inflammatory joint conditions like rheumatoid arthritis. Treatment involves anti-inflammatory and analgesic medications and avoiding activities that aggravate the condition. 6.3.5FROZEN SHOULDERFrozen shoulder is a condition where portions of the joint capsule form adhesions and stick together. It usually follows an injury to the shoulder such as tendinitis or bursitis. Lack of use due to the pre-existing injury causes the adhesions to form. Symptoms include loss of range of motion, acute pain on movement and aching when not in use. Treatment involves analgesics and anti-inflammatories to reduce the pain and an exercise program aimed at improving range of motion in the shoulder joint. If this is unsuccessful the adhesions may be removed surgically by arthroscopy. 6.4MUSCLE AND CONNECTIVE TISSUE DISORDERSOur muscles and the connective tissue structures that support them are what provide us with our strength and our ability to move. Our muscles work hard but sometimes they get overloaded and then injury occurs. 6.4.1CRAMPS AND SPASMSCramps and spasms are an involuntary contraction of a muscle, usually skeletal muscles. A cramp is a strong, painful short term condition. A spasm may be less strong but continues for a long period of time. There are five main causes of cramps and spasms:Nutritional deficiencies – calcium and magnesium deficiencies as well as dehydration can all cause cramps.Ischaemia – lack of oxygen means that the muscle cannot function properly.Exercise – muscle fatigue, dehydration, electrolyte imbalance and hyperthermia can all contribute to cramps. Over-excitation of the nerve fibres in the muscles is also a factor.Splinting – this is a reflexive response against injury. When the muscle reaches a point where it cannot safely stretch any further it goes into spasm to protect against injury. Neurological – some conditions affecting the nervous system such as multiple sclerosis can cause spasms. Treatment of cramps and spasms is to rest, restore any fluid or electrolyte imbalance. Avoid over-stretching or vigorous massage of the affected muscles as this could cause muscle fibres to tear. Gentle stretching may persuade the muscle fibres that it is ok to relax. Another method is reciprocal inhibition – by contracting the opposite muscle, it turns off the signals to the affected muscle causing it to relax. For example, if you have a hamstring cramp try contracting your quadriceps and hip flexor against resistance. 6.4.2TENDINITISTendinitis is different to a tendon strain. With this condition the tendon is inflamed but there is no actual tear. It is usually a symptom of overuse – repetitive low grade stress on the tendon causes inflammation.Signs and symptoms are those of inflammation. The condition is usually aggravated with exercise and relieved with rest.Treatment consists of anti-inflammatories, rest and avoiding the aggravating activity.If ignored the condition could progress to a grade 1 strain over time. 6.4.3PIRIFORMIS SYNDROMEThe piriformis muscle is one of the gluteal muscles and runs from the greater trochanter of the femur to the sacrum. Its main actions are abduction and lateral rotation of the thigh.The sciatic nerve which extends down the posterior of the leg runs either alongside or through the piriformis muscle. This means that when the piriformis muscle becomes tight it can press on the sciatic nerve causing sciatica – a radiating pain which travels down the back of the leg. Treatment involves massage and stretching to release the tight muscle as well as exercise therapy to prevent further tightening of the muscle. While piriformis syndrome is a common cause of sciatic pain, care should be taken to rule out other causes particularly herniation of a vertebral disc.4143375119380006.4.4ILIOTIBIAL BAND SYNDROMEIliotibial band (ITB) syndrome is a common overuse condition seen mainly in athletes or those partaking in regular endurance exercise. The ITB is a long section of connective fascia that reinforces the tensor fasciae latae (TFL) muscle running along the posterior aspect of the thigh from the pelvis to the knee. The TFL flexes and abducts the thigh as well as rotating it medially.The ITB runs across the lateral epicondyle of the femur to attach to the tibia. Friction can occur at the point where it crosses the femur.The condition is most likely to occur due to repetitive bending and straightening of the knee such as distance running. Running downhill especially aggravates it because of the hyperextension. People with anatomical abnormalities such as bow legs or torsion are also more susceptible. 6.4.5SHIN SPLINTS42144959271000The correct definition is an inflammation of the connective tissue covering the tibia (shin bone). However it is often used to refer to a variety of conditions including muscle and tendon strains and stress fractures of the tibia.All these conditions have similar symptoms and causes and it is difficult to distinguish between them without scans. Pain from shin splints can be mild or severe and the exact location of the pain depends on the actual injury. The cause of shin splints is usually an overuse injury. It is common in sports like distance running which cause repetitive stress. The main reasons for developing shin splints are a sudden increase in training load or too much running on hard surfaces with too little shock absorption in the feet and shoes. Overtraining, including increase in training schedule, causes strain on the muscles making them tighten. The muscles of the shin including the tibialis anterior attach along the length of the tibia. When they tighten they put pressure on the periosteum – the outer covering of the bone – causing inflammation and possibly small tears. Lack of shock absorption can cause inflammation of the tibia itself and also lead to stress fractures. Treatment includes rest, anti-inflammatories and changing exercise routines. 6.4.6PLANTAR FASCIITISThe plantar fascia is made from thick fibrous connective tissue that runs along the plantar (bottom) surface of the foot from the calcaneus to the metatarsals. When this area becomes tight or inflamed due to overuse it can become painful to walk. 337629544958000The condition is most commonly found in runners and in people who over-pronate when they walk.The main reason why plantar fasciitis develops is due to overuse or poor alignment of the foot however the following risk factors can increase the risk:Pronation of the footFlat archesObesityPoorly fitting shoesStiff-soled shoesOver-stretching of the footTight calf muscles or Achilles tendonTreatment consists of anti-inflammatories, rest, gentle stretching, massage, avoiding activities that exacerbate the condition.Orthotics or support shoes can help in many cases however care should be taken because over-aggressive or overly stiff orthotics or shoes can aggravate it further. If left untreated heel spurs can occur which are a calcification of the plantar fascia where it connects to the calcaneus. 6.4.7TENNIS ELBOWTennis elbow is one of the most common overuse injuries. It is an inflammation of the tendons of the forearm extensor muscles where they insert into the lateral epicondyle of the humerus. These are the muscles that lift the hand and the wrist.Symptoms are pain on the lateral side of the elbow joint particularly when rotating against resistance such as turning a door handle, loss of strength and difficulty gripping objects.Contributing factors to the development of tennis elbow include:Playing racquet sports like tennisLack of strength in the forearmPoor technique when playing sportsRepetitive movements of the hand and armContinuously lifting heavy loadsTreatment involves anti-inflammatories to reduce pain and modifying activities which cause the pain. 6.4.8CARPAL TUNNEL SYNDROME4028440-11874500The carpal tunnel is made up of the carpal bones of the wrist and the transverse carpal ligament that spans across them to hold the flexor tendons of the wrist in place. The median nerve runs through the carpal tunnel and can cause pain if pressure is placed on it. Pain is felt in the medial side of the hand and wrist and can also radiate up the forearm. Tingling or numbness can also occur.There are three main reasons why it can occur:Oedema – fluid retention and swelling in the wrist. This can be caused by obesity or hormonal imbalance from menopause or pregnancy.Subluxation – displacement of the carpal bones often due to trauma such as falling onto the wrist.Fibrosis – the most common cause. Repetitive strain causes inflammation of the tendons and the carpal ligament which leads to a build-up of fibrous tissue in the carpal tunnel putting pressure on the nerve.People most at risk from fibrotic carpal tunnel syndrome are those who spend many hours a day at a computer.Treatment consists of anti-inflammatories to reduce swelling and relieve pressure on the nerve. A wrist splint will help to support the wrist. In severe cases surgery may be required to remove some of the fibrous tissue. 3562350283210006.4.9FIBROMYALGIAFibromyalgia is a condition causing chronic pain in the muscles, tendons, and ligaments. It can also cause spasms, stiffness, fatigue and sleep disturbance. Many patients also have chronic fatigue syndrome however this may be due to sleep disturbances caused by the fibromyalgia. It is characterised by a predictable pattern of tender points in the muscles initially concentrated around the neck, shoulders and back but which can go on to affect all muscles. Pressing on these points with just a light pressure will elicit an abnormal pain response. In order to give a confirmed diagnosis at least 11 out of 18 points must be active and the condition must last for 3 or more months with no other diagnosable cause of the pain. The cause of fibromyalgia is unknown although there is often a triggering factor such as arthritis, injury, physical or emotional stress. Many sufferers have abnormally high levels of certain neurotransmitters including substance P which is involved in the transmission of pain nerve impulses to the brain.Fibromyalgia is not considered to be an autoimmune condition. Fibromyalgia is more common in women than men and usually starts in middle age. There is no known cure but it can be treated with pain medication. Other treatments include stress management, improving sleep quality, relaxation techniques, cognitive behaviour therapy and massage.LESSON 7 – INTEGUMENTARY DISORDERS7.1Infectious Conditions7.1.1Boils7.1.2Impetigo 7.1.3Cellulitis7.1.4Herpes7.1.5 Warts7.1.6Tinea 7.1.7Lice 7.2Non-Infectious Conditions7.2.1Acne7.2.2Rosacea7.2.3Contact Dermatitis7.2.4Eczema7.2.5Psoriasis7.2.6Vitiligo7.2.7Ulcers7.2.8Scars7.3Neoplastic Conditions7.3.1Moles7.3.2Carcinomas7.3.3Melanomas7.1INFECTIOUS CONDITIONSOur skin provides a protective barrier between the inside of our body and the outside world. It provides a large part of the first line of defence of our immune system. While our skin is good at resisting many of the pathogens that try to enter our bodies, sometimes infection can still take place.The next part of this lesson looks at some of the common skin infections that can occur. 7.1.1BOILS424815024003000Boils are also known as furuncles. They are infections of the sebaceous glands in the hair follicles, usually with Staphylococcus aureus (Staph A) bacteria. Staph A normally lives on the skin without causing infection but when our immune system is low or the skin is broken infection can occur. Boils are red, raised lumps on the skin which become filled with pus as they develop. As they become larger they also become increasingly painful.Sometimes a collection of boils occurs in a small area and become connected. This is known as a carbuncle. Boils are not dangerous as long as the infection stays localised. Initial treatment consists of hot compresses to try and draw out the pus. A doctor may lance the boil but this should not be done at home as it may cause further infection. Antibiotics can be prescribed but they are best reserved for people with incurrent infections.Staph A is contagious and can be spread by physical contact with an infected person. 4248150114935007.1.2IMPETIGOImpetigo is also known as school sores because it often affects children. It is caused by either the staphylococcus or streptococcus bacteria. Initial symptoms are a rash of small red blisters or pustules filled with clear fluid. They later rupture and become covered with a honey-covered crust. The infection often starts when the skin has been damaged by some other injury. It is often itchy. The most common sites are the face and ears. Treatment is usually with a topical antibiotic treatment. If this fails to work then oral antibiotics can be given.Impetigo is highly contagious and care needs to be taken to avoid cross-contamination. The patient should be discouraged from scratching itchy lesions as they can spread the infection to another part of their own body by touching. Clothing and bed sheets need to be washed daily. Avoid physical contact with patients or with surfaces that they have touched. 7.1.3CELLULITISCellulitis is an infection of the deeper layers of the skin – the dermis and/or subcutaneous layer. It is usually due to either the streptococcus or staphylococcus bacteria but can also come from other sources like infection from animal bites. Bacteria can often enter through existing wounds. The most common site of infection is the legs but it can also be found on other body parts. The infection manifests as a tender, red, swollen plaque which can spread. It is often accompanied by pain, oedema and fever. Infection often spreads to lymph nodes. Repeated or long term infection can lead to damaged lymph nodes causing lymphedema. There is a potential to develop septicaemia which is an infection of the blood or necrosis (tissue death). Septicaemia can lead to organ failure including liver and kidneys.Treatment involves oral or intravenous antibiotics depending on the extent and severity of the infection.4048125302260007.1.4HERPESThere are two types of the herpes simplex virus. Herpes simplex I causes cold sores while herpes simplex II causes genital herpes. Both types are highly contagious. Both types are transmitted through mucous secretions – either oral or genital. It is possible for the two types to cross over with cross-contamination from one site to another. The virus manifests as cold sores or blisters on the affected area. There is often a feeling of itching or tingling for 2-3 days before the outbreak becomes apparent. The blisters gradually develop a crust and usually resolve within 1-2 weeks. An infected person continues to transmit the disease up to 3 days after symptoms have resolved and the virus can survive on surfaces which the person comes into contact with. It is easy to catch cold sores by sharing a glass of water. The initial outbreak usually occurs 2-20 days after coming into contact with the virus. The first outbreak may be almost unnoticed or it may be accompanied by swollen lymph nodes and fever. Subsequent outbreaks can be triggered by illness, sunburn, cold, stress or other factors.4171950-13970007.1.5WARTSWarts are caused by the human papilloma virus (HPV). There are more than 80 different types of HPV. They include the types that cause warts on the hands and feet as well as the types that cause genital warts. They can also occur in other areas.Warts on the soles of the feet are known as plantar warts or verrucae. Warts manifest as small, raised, irregular shaped lumps, often with a greyish appearance. They can be tender or itchy.Warts can be transmitted by direct skin-to-skin contact or by skin-to-surface contact. They usually enter the body through breaks in the skin. Plantar warts are frequently transmitted at swimming pools as the virus can live on the tiled floor until it enters the skin of another person which has been softened by time spent in water. Treatment is aimed at removing the wart. The main treatments are the application of salicylic acid which breaks down the wart or by freezing it off. Laser surgery and antiviral therapy are also sometimes used. An unusual method which seems to work is occluding the wart with duct tape. The duct tape should be left on for 6 days a week up to 2 months until the wart resolves. The reason it works is not known. Theories are that it stimulates the immune response, or that the skin surface comes away when the duct tape is removed taking the virus cells with it. 7.1.6TINEATinea is caused by infection with fungi called dermatophytes (derm = skin). Tinea is named differently depending on the part of the body affected:Tinea corporis – body or faceTinea capitis – scalpTinea pedis – feetTinea unguium - nails460883020510500Tinea CorporisTinea corporis occurs on any part of the body other than the scalp of feet. It is also known as ringworm because of its appearance, but there are no worms involved. It has the appearance of wide, flat, red lesions which are circular or oval in shape. They spread and grow in size and the central area often clears as the area grows. The lesion can be itchy or tender.461010020320000Tinea CapitisTinea capitis is characterised by inflamed lesions on the scalp often accompanied by hair loss in the affected area. They are usually on the back of the head. A scale or crust can develop. There is a high risk of a secondary bacterial infection.453390020002500Tinea PedisTinea pedis is also known as athlete’s foot because it is often found in people whose feet become hot and sweaty from being enclosed in shoes during exercise. Tinea pedis can be mild or can be painful with inflamed lesions, peeling or fissured skin. It can often produce itching. 461010016319500Tinea UnguiumTinea unguium is a fungal infection of the nails, usually the toenails. The nail initially turns white then yellow or brown. The nail thickens and cracks as the nail bed becomes infected. TreatmentDefinitive diagnosis is made by taking a skin scraping to be analysed. Initial treatment is usually by topical antifungal medications. This can take a long time and discipline and patience is required.It is important to avoid re-infection by washing shoes and socks, cleaning combs and hairbrushes depending on the part of the body affected.When topical treatments are ineffective oral antifungal medications can also be used. These are only prescribed after diagnosis has been confirmed by analysis of skin scraping.Oral antifungals can have an adverse effect on the liver so they should only be used when topical treatments fail to work and liver function should be monitored. 7.1.7LICEInfection with lice is known as pediculosis. Lice are small insect from the genus pediculus which like to live on humans and animals as parasites. They live off blood and lay their eggs at the base of the hair. The different types of pediculosis are named for the areas of the body in which they occur:39052502857500Pediculosis capitis – headPediculosis corporis – bodyPediculosis pubis – pubic and genital areasIt is a misconception that people with lice are dirty as they prefer clean skin and hair. Lice are easily transmitted from one person to another as they are able to jump. They can also be transferred from animals to humans. Lice are small grey-brown wingless insects which are big enough to be seen without a microscope. The eggs are white in colour and are known as nits. They are attached to the base of the hair shaft. Treatment is application of pesticidal soap or shampoo. Persons who are allergic to pesticides can choose to attempt to smother the lice with petroleum jelly or olive oil but this is less effective. Nit combs are fine-toothed combs which are used to manually remove the eggs from the hair. Repeated treatments may be needed once a week to catch any new lice that hatch from eggs.Lice can be removed from clothing by washing and drying them at high temperature or by leaving them in a sealed plastic bag for 2 weeks. Hair brushes and combs should be treated with pesticide after use. Bedding and towels should also be washed and kept clean to prevent re-infestation. 7.2NON-INFECTIOUS CONDITIONSWhile there are many infectious skin conditions, there are also many that are not infectious and cannot be passed from person to person. These may be caused by immune dysfunction, hormone imbalance or other causes.6.2.1ACNE34480508128000Acne vulgaris is a condition that will affect most people at some time in their lives. It is an inflammatory condition with small, localised skin infections usually of the sebaceous glands. Acne is a bacterial infection – usually staphylococcus – but unlike boils it is not contagious, nor is it so severe. It is found mainly on the face, neck and upper back but can also appear on other parts of the body. Sebaceous glands in the hair follicles produce sebum which helps to moisturise the skin and hair. Acne occurs when these glands become blocked by dead skin cells, bacteria, hormones and extra oil. Stress and fatigue can contribute to the condition as well as cosmetics. Acne takes the form of small, raised lesions on the skin. They are named according to their appearance.Pimples – small red bumps, sometimes painful, with no visible sebum edomes – raised bumps containing sebum. Known as whiteheads or blackheads according to the colour of the sebum they contain.White comedomes are closed to the atmosphere so the sebum retains its original appearance. Black comedomes are open to the atmosphere so the sebum oxidises and changes colour. The black is not due to dirt. Cysts – deeper infections in the dermal layer, do not reach the surface.There are a number of factors that can contribute to the development of acne:Testosterone production – high testosterone levels during puberty increase sebum production by sebaceous glands which is why teenagers are susceptible to acne.Bacteria – bacteria colonise the hair follicles leading to inflammation.Stress – upsets the hormonal balance and lowers the immune system.Liver congestion – poor nutrition and lifestyle choices cause liver congestion making it difficult for the liver to neutralise high levels of testosterone.Cosmetics and skin products – can block pores and hair follicles leading to a build-up of sebum.Hormonal imbalance – hormonal changes such as contraceptive pills and menopause can lead to acne in mature women. Treatment for acne focus on clearing up existing lesions, preventing new lesions and preventing scarring. The main approaches are:Improve diet and lifestyle including reduction in processed and fatty foods.Improved personal hygieneAvoid oil based cosmetics and skin care productsTopical acne treatments including retinoids, peroxides and antibioticsOral antibioticsOral hormone treatmentsLaser surgeryIt is important to avoid squeezing pustules as releasing the contents onto the skin can spread infection. Trauma to the tissue can also increase the risk of scarring.Good personal hygiene and avoiding oily products on the skin are recommended but it is important not to go too far. Stripping the skin of all its natural oils will encourage high levels of sebum production which will exacerbate the problem rather than solve it. 7.2.2ROSACEAAcne rosacea is an inflammatory condition that causes redness of the skin primarily on the forehead, cheeks and nose. Unlike acne vulgaris, it does not produce comedomes. It usually appears in mid-life (30-50 years old). It is more common in women than men and in people with fair skin.421005051371500Rosacea is caused by inflammation accompanied by a vascular weakness which allows fluid and inflammatory mediators to leak into the dermis, although exactly what triggers this is unknown. Risk factors for developing the condition include:Alcohol consumptionSpicy foodsRegular, prolonged exposure to sunlight or strong windFair complexionThe condition initially manifests as a general redness of the skin. It starts with blushing that goes away, but progresses to a permanent redness or dark discolouration of the skin. Men in particular can develop rhinophyma – development of a large bulbous nose. People with rosacea are usually heat sensitive and should avoid vascular stimulants such as heat, sunlight, alcohol and spicy ical treatments are similar to those for acne vulgaris, including diet and lifestyle modification, topical acne treatments and topical antibiotics. Laser surgery can be used to remove individual blood vessels and reduce rhinophyma. 7.2.3CONTACT DERMATITIS440055016256000Dermatitis is defined as an inflammatory condition of the skin that is caused by an outside agent. There are two main types – contact dermatitis and atopic dermatitis which is also called eczema. In this section we will look at contact dermatitis. Contact dermatitis can be divided into:Contact irritant dermatitis – direct irritation of the skin by a substance with which it comes into contactContact allergic dermatitis – a type IV hypersensitivity reaction to allergens coming in contact with skinIrritant dermatitis is caused by direct irritation of the skin. Irritation can be mechanical (rubbing, chafing), chemical (cleaning products) or environmental (poisonous plants). There is no allergic response involved.Allergic contact dermatitis is caused by a type IV hypersensitivity response to an allergen. Type IV allergic responses are mediated by T cells and usually take 24-72 hours to develop. There are many different potential allergens – in fact over 2000 have been identified. Common examples are plants, metal alloys in jewellery, preservatives in cosmetics and latex. Symptoms of contact dermatitis are redness of the skin, dryness, vesicles (blisters), pain, itching and swelling. The symptoms of irritant dermatitis will be confined to the area of contact while allergic dermatitis may cover a larger area – although still localised. Both types of contact dermatitis can have acute or chronic forms. Acute episodes arise from a single exposure whereas the chronic form arises from continued exposure over a long period of time.Treatment for both types is aimed at removing the source of the irritant or allergen. In some cases this may be difficult for example someone whose employment brings them into regular contact with chemicals may need to change profession. An example of this would be a swimming instructor who is sensitive to chlorine. Topical treatments such as corticosteroid creams can help to reduce symptoms of inflammation and itching. 7.2.4ECZEMA458406518034000Eczema is the common name for atopic dermatitis. Atopic means a hypersensitivity response that is not localised to the site of contact. This is known as a type I hypersensitivity response. Eczema can occur in either childhood or adulthood and people with the condition often also suffer from asthma and hayfever which are other atopic conditions. 462851512192000Childhood eczema is characterised by redness, formation of vesicles (blisters) with oozing and crust formation. It often starts on the cheeks and can be found on the scalp, arms, torso and legs. It usually starts before 5 years old and resolves by 15 years old. Adult eczema is characterised by dry, red patches of skin on the face, neck and upper torso. It is also found in the creases of the elbows and knees. Both forms can have prolonged outbreaks with severe itching. Secondary bacterial infections are common due to broken skin. Although eczema is not linked to a specific allergy, many people find they are more prone to outbreaks if they eat certain foods or use certain products on their skin. Stress can also be a factor. Treatment is aimed at alleviating the symptoms of dryness, itching and inflammation. It is important to keep the skin clean and moisturised using products that do not cause irritation. Trigger foods and environmental irritants should also be avoided. Topical corticosteroids can reduce inflammation but prolonged use can cause thinning of the skin. Topical immunosuppressants can control outbreaks but increase risk of other infections. Anti-histamines can reduce itching and their sedative effects can also help deal with stress which can exacerbate the condition.Some studies have shown that probiotics can help in reducing type I hypersensitivity reactions. 7.2.5PSORIASIS39116002984500Psoriasis is a chronic inflammatory condition where excessive turnover of epithelial cells leads to a thickening of the skin. It is present in about 2% of the population. Psoriasis is characterised by well-defined red plaques of dry skin which are often covered with a silvery scale. Patches are often found on the knees and elbows but can also occur on any part of the body. It usually has acute phases followed by periods of remission. The cause is unknown but it appears to run in families. Outbreaks can be triggered by physical and emotional stress, skin damage, sunburn, hormonal changes and medications. It tends to be worse in winter due to the lack of sunlight.Psoriasis can be difficult to treat. Treatment is aimed at suppressing the symptoms. Topical treatments include moisturising agents, corticosteroid creams and salicylic acid. Oil based moisturisers are better than water based.Phototherapy treatment involves exposure to sunlight or UV light. This can be an effective treatment but needs to be used cautiously because too much exposure can exacerbate the condition. It also increases the risk of skin cancer.Since stress is a major component avoiding stressful situations and using relaxation techniques can be helpful. 7.2.6VITILIGO369125518796000Vitiligo is a pigmentation problem found in 1-2% of the population in which areas of skin lose their pigmentation. It is more common and also more noticeable in people with dark skin. The condition manifests as areas of skin that become pale or white in colour as they either lose the melanocytes or the melanocytes stop producing melanin. The areas are irregular in shape and can be large or small.Areas of depigmentation occur most commonly on the face, neck, arms and legs. These areas are very prone to sunburn because they have no melanin to protect them. The risk of skin cancer is also increased.The underlying cause is unknown but is thought to be either hereditary or autoimmune. There is no cure for vitiligo. Once an area has lost its pigmentation it cannot be recovered. Topical corticosteroids and UV therapy can slow the progress but both need to be used with caution due to side effects and risk of complications. Treatment usually centres around masking the condition. Self-tanning lotions, skin stains and cosmetics can darken the depigmented skin. Tattooing can be used but it is difficult to match the colour. In cases of extensive depigmentation, the person may prefer to use medications to destroy the remaining melanocytes thereby making all their skin white. This makes them vulnerable to sunburn and skin cancer.7.2.7ULCERSAn ulcer is a break in the skin or mucous membrane that fails to heal and that is often accompanied by inflammation. There are three main types of ulcer on the skin:Varicose ulcers – caused by lack of circulationDiabetic ulcers – complication of diabetes mellitus4947920127000Decubitus ulcers – pressure soresVaricose UlcersVaricose ulcers are caused by a lack of circulation. They are often a complication of varicose veins which impair venous return. The lack of circulation means there is less nutrients and oxygen available to heal any wounds that occur in the skin. Diabetic Ulcers49352205207000Diabetic ulcers usually occur in the lower legs and feet. They are caused by a combination of poor circulation, decreased nerve supply and decreased oxygen supply.436245024320500Decubitus UlcersDecubitus ulcers are also known as pressure sores or bed sores. They occur when a person is immobile for a long period. They are caused by ischaemia due to unrelenting pressure that impairs the flow of blood and lymph. They are mainly found in bony area such as the heels, hips or shoulders. The pressure from the weight of the bone stops blood supply to the tissue supporting its weight. Constant pressure for 2 hours is enough to cause ischaemia. Prevention and TreatmentPrevention of all types of ulcers is better than treatment. This can be achieved by maintaining circulation. To achieve this, it is important to avoid immobility. In the case of patients who are bedridden or have limited physical movement it may be necessary for the caregiver to move them on a regular basis. Treatment depends on the severity of the condition. Occlusive dressings will keep out any further infection as well as keeping wound fluid in place which is needed for healing. Severe long term ulceration may result in necrotic tissue which needs to be surgically removed. Skin grafts may also be required if the damage is too extensive. 7.2.8SCARSThe body has an amazing ability to heal itself. Often, tissues manage to regenerate to their original condition with no evidence that the injury even took place.Sometimes, the damage is too extensive or the cells have limited ability to regenerate so it may not be possible for the body to repair itself with the original type of tissue. In this case the body may repair itself with fibrous connective tissue which is easier to produce. These kinds of repairs with fibrous tissue are known as scars. The advantage of scar tissue is that it is often stronger than the original tissue that it is replacing, but the disadvantage is that it is also less flexible. Most scars on the skin will lay flat to the skin’s surface and be similar in colour to the original skin, though they may lack pigmentation and hair. These scars can fade over time and become less visible. 44291255524500Keloid ScarsKeloid scars occur when the scar becomes over-developed with more collagen than is required to repair the original injury. The scar becomes hypertrophic – that is, overgrown. It becomes raised from the skin. Some keloid scars continue to grow indefinitely. Keloid scars can be treated with cortisone to inhibit growth but this is not always effective. Methods used to remove keloids include radiotherapy, cryotherapy (freezing) and laser therapy.Keloid scars are more common on people with dark skin. 7.3NEOPLASTIC CONDITIONSNeoplastic conditions are abnormal growth of cells. These can be either benign (moles) or malignant (tumours).3676650276225007.3.1MOLESMoles or nevi are benign neoplasia where melanocytes replicate and become concentrated in a small area. They then produce melanin which gives the mole its colour. Most people have moles which can develop before or after birth. Most appear between 1-4 years of age. They begin as brown or black marks on the skin which can grow and may develop coarse hairs.It is important to distinguish moles from freckles which are just concentrations of melanin in the skin as opposed to moles which are made of melanocytes. Moles which develop after the age of 20, or which grow or change colour, are known as dysplastic nevi. They may be irregular in shape with a raised surface and are usually larger than normal moles (>5mm). These moles should be checked regularly as they are the most likely to develop into melanoma although only about 20% of melanomas arise from moles. 7.3.2CARCINOMASThere are two types of carcinoma:Basal cell carcinomaSquamous cell carcinoma462407015494000Basal cell carcinomaBasal cell carcinomas (BCC) are the most common accounting for around 75-80% of all skin cancers. They are the least dangerous as they are slow growing and non-metastasising but can grow large and deep if left untreated.They are most common in people who have had a high exposure to sunlight. They initially look like a pink or red nodule or plaque. As they grow they can develop ulcers in the centre which do not heal.459549533083500Although they do not metastasise they can still be dangerous because they erode the surrounding tissues including blood vessels and nerves.Squamous cell carcinomaSquamous cell carcinomas (SCC) These are the second most common type of skin cancer representing 10-20% of all skin cancers. They are most common on the ears, hands and lips.People exposed to industrial chemicals are the most likely to develop SCCs. They are similar to BCCs in that they are characterised by a sore that will not heal.SCCs are more dangerous than BCCs because they are faster growing and can metastasise. TreatmentTreatment for both types of carcinoma is by surgical excision. Radiotherapy may be appropriate for deep lesions or metastases. Patients will need to be checked for new carcinomas for the rest of their lives. 7.3.3MELANOMAS4086225825500Melanomas are the least common type of skin cancer representing only about 5-10% of all skin cancers but they are the most dangerous because they are malignant – that is they are fast growing and easily metastasise.Melanomas are neoplastic growths of melanocytes and can initially resemble moles. For this reason any new moles that develop after the age of 20 should be checked. The main cause of melanomas is exposure to UV radiation including tanning salons as well as direct sunlight. People with fair skin are more at risk because they have less melanin to protect them from the harmful UV radiation. Melanomas are usually larger than moles (>5mm) and irregular in shape. They are black or brown in colour and have a raised uneven surface. They may have surrounding inflammation and they may bleed or ulcerate from time to time. Early detection is important because they can metastasise quickly. People with dark tattoos should be especially careful as the melanoma may go unnoticed. Treatment is by surgical removal with chemotherapy where metastasis is suspected. LESSON 8 – EYES, EARS, NOSE AND THROAT8.1Eyes8.1.1Conjunctivitis8.1.2Stye8.1.3Cataract8.1.4Glaucoma8.1.5Macular Degeneration8.1.6Near-Sightedness8.1.7Long-Sightedness8.1.8Squint8.2Ears8.2.1Otitis Externa8.2.2Otitis Media8.2.3Tinnitus8.2.4Vertigo8.2.5Meniere’s Disease8.3Nose8.3.1Rhinitis8.3.2Sinusitis8.4Mouth and Throat8.4.1Mouth Ulcers8.4.2Gingivitis8.4.3Dental Decay8.4.4Tonsillitis8.4.5Laryngitis8.1EYESVision is our dominant sense, with nearly 70% of our sensory receptors located in the eyes. Sight is important to help us know what is going on around us and to keep us from running into danger. Any conditions that affect the eyesight can therefore have a significant effect on our independence and our quality of life. 8.1.1CONJUNCTIVITISConjunctivitis is an inflammation of the conjunctiva, the mucous membrane that lines the inside of the eyelids and the sclera of the eyeballs (it does not cover the cornea).The main purpose of the conjunctiva is to provide moisture in the form of mucous which lubricates the eye socket and prevents friction. Signs and symptoms vary according to the type and severity of conjunctivitis. They can include redness, inflammation, lacrimation (tears), itching, pain and photophobia. 414083552006500Causes of conjunctivitis include:Physical irritants (e.g. dust)Chemical irritants (e.g. chlorine from swimming pool)AllergensBacteriaVirusesAllergic ConjunctivitisAllergic conjunctivitis is a type I hypersensitivity disorder. It is usually seasonal and accompanies hayfever. The main symptoms are redness, tearing and itching.Treatment includes avoiding allergens, anti-irritant eye drops and antihistamines.Bacterial conjunctivitisBacterial conjunctivitis is a highly contagious condition. It is usually caused by streptococcus or staphylococcus bacteria. It often accompanies other bacterial or viral infections due to lowered immune system.Signs and symptoms include redness, pain, itchiness, burning, a ‘gritty’ sensation and tearing. A white or yellow discharge may also occur. The eyelids can become sticky with crusting in the corners and on the eyelashes. The patient may find that the eyelids stick together when they wake in the morning. The condition is usually self-limiting, lasting 10-14 days if untreated, but can become chronic.Treatment is with antibiotic eye drops. Oral antibiotics can also be used if eye drops are unsuccessful. The condition is highly contagious so care must be taken to wash the hands after any contact and not transfer infection from one eye to the other or to another person. Viral conjunctivitisThis is less common than bacterial conjunctivitis. Even when the patient has a cold virus, chances are the conjunctivitis is due to bacteria.Viral conjunctivitis, when it does occur, is highly contagious. It is usually due to either adenovirus or herpes virus.Manifestations include redness and tearing. There is no white or yellow discharge. There is no treatment for the viral infection which is usually self-limiting to about 2 weeks but antibiotic eye drops may be given to prevent a secondary bacterial infection.It is very highly contagious so it is very important to avoid passing the virus to another person by careful hand washing and avoiding contact. Patients should avoid wearing contact lenses and wear prescription glasses until the infection is resolved.4570730167640008.1.2STYEA stye is a bacterial infection of the sebaceous glands at the base of the eyelashes, usually staphylococcus. It produces a red, inflamed, painful lump which may contain pus.The condition is usually self-limiting but can be treated with topical or oral antibiotics.8.1.3CATARACT44157906477000A cataract is a condition where the lens of the eye becomes opaque and does not allow light through to the retina. There are many reasons why cataracts can occur including:Age – fibres in the lens become compressed and dehydrated and electrolytes like sodium, potassium and calcium become more concentrated leading to opacity.Metabolic disorders – e.g. diabetes mellitusUV light – long term exposureSmokingMedications – including corticosteroidsInjury – direct trauma to the eye, heat or radiationCongenital – cataract present at birth. Can be genetic defect, maternal infection (e.g. rubella) or maternal intake of toxins (e.g. smoking)As the cataract develops the pupil of the eye develops a white appearance. Vision will become blurry and distorted, affecting both near and distant vision. The only treatment for cataract is surgery to replace the lens.8.1.4GLAUCOMAGlaucoma is the name given to conditions involving an increase in intra-ocular pressure (pressure inside the eye). As you will have learned in anatomy and physiology, the front section of the eye is filled with a fluid called aqueous humour. The amount of fluid can build up causing pressure due to:Increased rate of secretion of aqueous fluidResistance to flow rate between iris and ciliary body (so fluid cannot move within the eye and builds up in one areaReduced rate at which fluid leaves the eye (between iris and sclera)-142875-381000Risk factors for developing glaucoma include:Age Family historyDiabetesHypertensionHyperthyroidismHistory of migrainesThe manifestations of glaucoma depend on severity of the condition. Mild forms can be asymptomatic (no symptoms). As it progresses, they include:Loss of visionPain in and around the eyeRedness of the eyeEnlarged pupilHeadachesNauseaTreatment is initially aimed at reducing intraocular pressure through medications. If necessary, laser surgery can be performed to create an opening in the iris to allow the fluid to pass through and bypass any blockage so that the pressure does not build up again. Treatment is important because the increased pressure can damage the optic nerve fibres leading to permanent vision loss.8.1.5MACULAR DEGENERATIONThe macular is the central part of the retina which contains the highest number of cones, the photoreceptors that are responsible for detailed vision and seeing colours. Metabolic waste products can accumulate in this area because of the high number of cells and their high level of metabolic activity. These waste products cause degeneration of the cells leading to loss of vision.Macular degeneration is usually caused to age. The exact cause is unknown but there appears to be links to genetic factors, cigarette smoking, poor diet and cardiovascular disease. 36861757747000There are two types of macular degeneration:Dry - the accumulation of waste products damages the cells leading to atrophyWet – as above, but there is also the development of new blood vessels which leak fluids, protein and other substances that cause damage and scar tissue. Once scar tissue has formed the damage is irreversible.Symptoms of the disease include:Loss or distortion of the central part of visionDevelopment of a ‘blind spot’Difficulty reading or seeing close objectsDifficulty seeing in poor lightTreatment options are limited. There are no effective treatments for the dry form although its progress is slow and may develop into the more serious wet form.Progression of the wet form can be slowed by injections into the eyes of VEGF inhibitors, a class of drugs which inhibits the growth of new blood vessels. This treatment is both painful and expensive.Laser therapy can be used to target the abnormal blood vessels but this is not suitable for all cases.3868420-271780008.1.6NEAR-SIGHTEDNESSNear-sightedness is also known as myopia.It occurs when distant objects focus in front of the retina rather than on it. People with myopia can often see close objects clearly but distant objects are blurred. It often occurs when the eyeballs are too long.The condition can be treated with corrective lenses or laser surgery. It is a condition that does not usually deteriorate with age since the intrinsic muscles of the eye are not used in distance vision. 385191043815008.1.7LONG-SIGHTEDNESSLong-sightedness is also known as presbyopia.Presbyopia can occur when the eyeball is too short so that distant objects focus behind the retina instead of on it. This can occur when the eyeball is too short. In this case, people can usually see distant objects they may have trouble seeing close objects because the amount by which the ciliary muscles would have to pull on the lens in order to focus is just too much.Presbyopia can also occur in older people. Just like other muscles in the body, the ciliary muscles in the eye become weaker and stiffer with old age so they are less able to alter the shape of the lens. 8.1.8SQUINT436943511557000A squint is also known as strabismus. Strabismus is an abnormal alignment of the eyes – usually horizontal – arising from either a weakness of the extrinsic eye muscles or a neurological disorder. This results in diplopia (double vision). The condition usually begins in childhood. A squint is usually concomitant – that is the misalignment remains constant regardless of which direction the person is looking. Occasionally it can be incomitant in which the degree of misalignment varies. The latter type is usually due to muscle weakness or paralysis, as the weaker eye does not move as much as the stronger one.The brain learns to compensate for the misalignment by either accepting signals from each eye alternately or by ignoring the weaker eye. It is important to treat the squint because over time this can lead to a functional blindness in the weaker eye.Treatment involves eye exercises to strengthen the weak muscles or by placing a patch over the stronger eye which forces the child to use the weaker one.8.2EARSOur ears control not only our sense of hearing but also our sense of balance. Disorders of the ear can affect both. 8.2.1OTITIS EXTERNAOtitis externa is an infection of the outer ear, usually by bacteria. It can also be caused by fungal or viral infection or an allergic reaction.Manifestations are inflammation, redness, pain, itching and discharge. Heavy discharge can block the ear canal leading to temporary deafness.The condition can be exacerbated by moisture in the ear from swimming or sweating. It can also be made worse by attempting to clean the ear with cotton buds which can push discharge, earwax or debris further into the ear.Bacterial infections can be treated with either topical or oral antibiotics. The patient should avoid getting the ear wet until the infection is resolved.8.2.2OTITIS MEDIAOtitis media is an inflammation of the middle ear commonly caused by a bacterial or viral infection. It is often a complication of the common cold.Otitis media often involves the eustachian tube which connects the middle ear to the sinuses. The condition is more common in children up to 3 years old because their eustachian tubes are shorter and more horizontal than adults which makes them more susceptible to infection. Bottle feeding infants puts them in a supine position which increases risk.Manifestations of otitis media include:Severe persistent earache408622526860500Small children may constantly put their finger in their earIrritability and poor sleep patterns in infantsInflammation of tympanic membrane (eardrum)Rhinitis (inflammation of nasal passages and sinuses)Hearing lossFever NauseaLong term otitis media can affect intellectual and social development in young children because of the effect on hearing.Treatment includes anti-inflammatories and antibiotics. Where the condition does not resolve a tube may be surgically implanted in the tympanic membrane to allow draining of fluid. Children with tubes inserted should not immerse their heads in water or go swimming because water can enter the middle ear via the tube causing further damage.8.2.3TINNITUSTinnitus is the presence of a persistent, abnormal noise in one or both ears without any external stimuli. The noise may be a ringing, hissing, buzzing, humming or roaring.Tinnitus is mostly commonly experienced in people between 40-70 years of age. The causes of tinnitus are varied including:Ear infectionBlocked ear canalNoise-induced hearing loss (e.g. industrial machinery, loud music)Meniere’s disease (see section below)HypertensionHead traumaMedicationsFood allergiesNicotineStimulants (e.g. caffeine)Treatment of the condition involves eliminating the cause where possible. Stress reduction and relaxation techniques can help to deal with the symptoms. Some people find that playing music or some other type of noise masks or inhibits the tinnitus. 8.2.4VERTIGOVertigo is a disorder of vestibular function where the person experiences a sense of motion. This can be:The person feels like they are movingThe person feels like they are still but the environment is moving.Our sense of balance and equilibrium is controlled by the semicircular canals in the vestibular system of the inner ear, which you will have learned about in anatomy & physiology. There are three semicircular canals connected by a central vestibule. When our head changes position, fluid in the canals moves and receptors tell our brain what position our head is in. About 85% of vertigo is due to injury or inflammation of the inner ear with the other 15% being due to a problem with the central nervous system. There are a number of causes including:InfectionTraumaMedications or toxinsAllergyAlcoholOrthostatic hypotension (blood pressure drops when standing up)Treatment is to remove the underlying cause where possible.Motion SicknessMotion sickness is a sensation of dizziness and nausea when moving. The exact cause is unclear but it seems to be triggered by an inconsistency between signals sent to the brain by the eyes and the ears. This is why it is triggered by reading a book while sitting in the car.The best way to avoid motion sickness is to look at the external environment while travelling. Anti-emetic medications are another possible treatment.8.2.5MENIERE’S DISEASEMeniere’s disease is a condition where a build-up of endolymph – the fluid in the inner ear – which leads to a triad of:VertigoTinnitusHearing lossThe cause of Meniere’s disease is unknown although it sometimes develops after a viral infection.Manifestations of the condition include:Periodic episodes of tinnitusFeelings of ear fullnessPeriodic episodes of severe vertigo with a need to sit or lie stillFallingNausea Periodic hearing lossAs the disease progresses, the hearing loss gets more severe and constant while the vertigo gets less.Treatment involves trying to reduce the endolymph fluid by medication including sedatives, corticosteroids and diuretics. Surgical interventions include a stent to drain the excess fluid or sectioning the vestibulocochlear nerve which connects the inner ear to the brain.8.3NOSEThe nose is hard to ignore. It’s stuck there right in the middle of the face. The nose provides the external opening to the respiratory system and also provides our sense of smell. It provides a first line of defence against pathogens wanting to enter the respiratory system. This also means that pathogens that are not destroyed or eliminated can lodge in the nose and surrounding sinuses and cause infection.8.3.1RHINITISRhinitis is an inflammation of the nasal passages. It can be either:Infectious – viral or bacterialAllergicThe condition can be exacerbated by cold environment, inhalation of dust or irritants or excessively dry air.Infectious RhinitisThe manifestations of infectious rhinitis are inflammation of the nasal mucosa, narrowing of the nasal cavities, headache, facial pain, fever and decreased sense of smell. The most common cause of infectious rhinitis is a viral infection. Viral rhinitis is usually self-limiting and lasts about 5-7 days.Bacterial rhinitis is likely to arise as a complication from a viral infection or in those who are immunocompromised. Bacterial infection should be suspected if the condition worsens after 5-7 days or continues for more than 10 days.Sometimes acute rhinitis can become chronic if the infection fails to clear or if there are recurrent infections.Treatment includes mucolytic agents (break down mucous), anti-inflammatories and decongestants. Antibiotics should only be given where a bacterial infection has been confirmed. They will not help a viral condition and may lead to antibiotic-resistant infection.Allergic RhinitisAllergic rhinitis is a hypersensitivity response to airborne allergens and is commonly associated with hayfever.Allergic rhinitis can be either seasonal or perennial depending on the type of allergen. Seasonal rhinitis will increase at times when the allergen is more abundant – for example high levels of pollen in spring. Perennial rhinitis is triggered by allergens that remain more constant such as dust or traffic pollution.Symptoms of allergic rhinitis include itching, sneezing, nasal discharge and congestion. Treatments include avoidance of allergens and anti-histamines. In severe cases corticosteroids may be prescribed.8.3.2SINUSITISSinusitis is an inflammation of the paranasal sinuses that are situated in the sphenoid, ethmoid, maxilla and frontal bones. The sinuses are spaces that make the bones of the skull lighter. They also produce mucous which warms and humidifies the air we breathe in and protects the airways. Causes of sinusitis are the same as for rhinitis – they can be viral, bacterial or allergic. Manifestations include headaches and facial pain over the affected sinus which is worse in the morning. There may also be some nasal discharge. Sinusitis often occurs together with rhinitis.Treatment is with anti-inflammatories. Antibiotics may be given if a bacterial infection is suspected. 8.4MOUTH AND THROATThe mouth and throat provide the opening of both the respiratory and digestive systems to the outside world. They allow oxygen and nutrients to enter our body. They also provide a first line of defence against pathogens. 8.4.1MOUTH ULCERS394335018415000Mouth ulcers are also known as aphthous ulcers. They are small lesions in the epithelial lining of the oral cavity. The lesions appear white in colour with surrounding inflammation. They can be extremely painful and usually last about 7-14 days.The cause is unknown but may be due to bacteria, virus, autoimmune or nutritional deficiency. Treatment is limited to alleviating the pain with topical medications. 389572542545008.4.2GINGIVITISGingivitis is an inflammation of the gums which surround the teeth. It is relatively painless but the gums can bleed on brushing. If untreated inflammation can spread to the periodontal ligament which anchors the tooth to the bone leading to tooth loss. The condition is caused by a build-up of bacterial plaque on the teeth and can be prevented by regular flossing and brushing. Gingivitis has been linked to cardiovascular disease although it is unclear whether it contributes to cardiovascular disease or is a symptom.8.4.3DENTAL DECAY40474902286000Tooth decay is also known as dental caries. Our teeth are covered with a hard external coating called enamel. Bacteria in the mouth react with dietary carbohydrates to produce an acid which can break down the enamel coating. Once the decay eats right through the enamel, the soft interior of the tooth becomes infected leading to inflammation and acute pain. It can also create an abscess at the base of the tooth. Treatment involves removing any infected tissue and repairing the hole with amalgam. If the damage is extensive or an abscess has formed it may be necessary to remove the whole tooth. Medications include antibiotics to treat infection, anti-inflammatories and analgesics for the pain.Tooth decay can be prevented by regular brushing and flossing and avoiding sugary foods and drinks which feed the bacteria. 4381500141605008.4.4TONSILLITISThe tonsils are collections of lymphoid tissue on either side of the back of the mouth and have an important role to play in protecting the body from pathogens. Unlike lymph nodes, they are not surrounded by a capsule so they easily absorb pathogens. This helps them in their role as part of our immune system, but it also makes them vulnerable to infection.Tonsillitis is an inflammation of the tonsils due to either a viral or bacterial infection. It usually occurs as part of a general respiratory tract infection. The inflamed tonsils are red, swollen and painful and may be covered in white spots which are caused by exudate.Bacterial tonsillitis is treated with antibiotics. If chronic tonsillitis develops, in which there are recurrent infection, the tonsils may be removed surgically. Surgical removal has become less common in recent years.8.4.5LARYNGITISLaryngitis is an inflammation of the larynx. It is usually due to viral or bacterial infection and occurs as part of a general respiratory tract infection. It can also occur due to tobacco smoking. The inflammation creates exudate and increased mucous production which can lead to coughing. Inflammation of the vocal cords which are contained in the larynx can lead to hoarseness of voice. LESSON 9 – RESPIRATORY DISORDERS9.1Infectious Conditions9.1.1Common Cold9.1.2Influenza9.1.3Acute Bronchitis9.1.4Pneumonia9.1.5Tuberculosis9.1.6Whooping Cough9.2Chronic Obstructive Pulmonary Disease9.2.1Emphysema9.2.2Chronic Bronchitis9.2.3Asthma9.3Environmental Lung Disease9.4Lung Cancer9.5Cystic FibrosisThe respiratory system allows the exchange of gases – oxygen and carbon dioxide – between our body and the outside world. Oxygen is vital for all of our cells to survive. The respiratory system consists of the mouth, throat, trachea, bronchi and lungs. We have already looked at mouth and throat conditions and this next lesson focuses on the lower respiratory system. 9.1INFECTIOUS CONDITIONSOur lungs are quite good at defending against invasion by pathogens – they have to be, as they are in the air we breathe all the time.When infection does take hold, it spreads easily due to the warm moist environment which is ideal for pathogens to survive and multiply.Respiratory infections are one of the most common reasons why people visit their doctors. Most respiratory infections are viral, but fungal and bacterial infections are also possible. 9.1.1COMMON COLDThe common cold is a viral infection of the upper respiratory tract and occurs more frequently than any other type of infection. It is found more in children than adults as their immune systems are still developing. Children may have 4-6 colds a year while adults only have 2-4 colds. They are a major cause of absenteeism from school and work. It was once thought that the common cold was just one virus, but in fact there are over 200 different viruses that can cause it. These include adenoviruses, rhinoviruses, parainfluenza viruses and respiratory syncytial virus (RSV). RSV is very common in children under 3 years old and is also most severe in this age group.Cold viruses are easily spread from person to person. They can pass by direct contact, indirect contact (touching a surface that an infected person has also touched) and are also airborne. The most contagious stage is in the first 3 days of symptoms. It takes about 5 days for symptoms to appear after infection takes place.The manifestations are blocked nose, nasal discharge, mild fever, sore throat, cough and headache. It usually lasts for about 2 weeks. There is no cure for the common cold so the treatment is based on alleviating symptoms with decongestants, analgesics and cough suppressants. Vitamin C and zinc are sometimes given to boost the immune system. Care needs to be taken with decongestants as many of them are also stimulants.9.1.2INFLUENZAWhen most people talk about having the ‘flu’ they mean a common cold virus. Actual influenza is a different, altogether more serious viral infection. Most people will get influenza at least a couple of times in their lifetime. For most people it is no more than an unpleasant experience, but for vulnerable groups like children and the elderly it can potentially be lethal. The initial signs and symptoms are similar to those of a cold – headache, nasal congestion and discharge, sore throat and cough. The main difference is that they are more severe and have a more rapid onset. Influenza is also characterised by a high fever, fatigue and muscle aches and pains.There is a risk of secondary infections, particularly within vulnerable groups, of viral or bacterial pneumonia or bronchitis. These secondary infections together with the high fever are what constitute the high risk.Treatment usually centres around alleviating symptoms – rest, analgesics, decongestants, cough medicines and keeping hydrated especially during fever. There are some antiviral medications available but these are expensive so are usually reserved for severe cases. They need to be taken within 48 hours of symptoms developing in order to be effective. Antibiotics do not work against viruses so they should be saved for bacterial complications like pneumonia and bronchitis.VaccinationInfluenza is a highly contagious airborne disease that can spread quickly through a population. Some strains can even transmit from animals to humans. The best way to prevent this spread is through vaccination programs.The virus mutates easily, with new strains developing each year. This is why it is important to get a flu vaccine annually, especially for vulnerable people including children, elderly and pregnant women. The vaccine is updated to include the strains that scientists believe will pose the biggest risk that year. 9.1.3ACUTE BRONCHITISAcute bronchitis is an inflammation of the bronchial tree – the bronchi and bronchioles – as the result of a viral or bacterial infection. It is usually self-limiting, lasting a few weeks.It is usually a complication of the common cold or influenza but can also happen separately. It can also be a complication of other diseases like measles. It is more common in vulnerable groups like children, elderly and those with a compromised immune system.Manifestations of acute bronchitis are inflammation and swelling of the bronchial tubes, increased mucous production, coughing and wheezing as air moves through the obstructed passages. The cough may last several weeks after other symptoms have passed.Treatments are similar to those for colds and influenza – rest, keeping hydrated. Antibiotics are not effective as it is usually caused by a viral infection. Breathing warm moist air helps to dissolve the mucous. Cough medicines can be used to treat the coughing. Cough suppressants can be used at night to help the person sleep, but coughing is important to clear the mucous out of the lungs otherwise the infection can become chronic. Expectorant medications encourage coughing to help clear mucous. Bronchodilators help to widen the airways and make breathing easier.3362325198755009.1.4PNEUMONIAPneumonia is an inflammation of the alveoli of the lungs. The alveoli are the air sacs which allow the exchange of oxygen and carbon dioxide between the lungs and the blood. The alveoli are small delicate structures with thin walls to allow gas exchange. When infection enters the lungs, they fill up with fluid and mucous which can damage them easily. In severe cases this can lead to permanent scarring of the lungs.Pneumonia is usually either viral or bacterial in origin, resulting as a complication of other infections like a cold or influenza. It can have either a sudden or gradual onset.Manifestations of pneumonia include: coughing, chest pain, cyanosis (from lack of oxygen), shortness of breath, mucous production, fever, muscular aches and pains and fatigue.Bacterial pneumonia can be treated with antibiotics. Other treatments are rest, breathing humidified air, oxygen supplementation if necessary and physical therapy to clear the chest by loosening mucous and encouraging coughing.Those with a lowered immune system due to other illnesses are at a higher risk of serious complications. People who are bedridden or paralysed are especially vulnerable because they have a reduced cough reflex. 9.1.5TUBERCULOSISTuberculosis is a bacterial infection which predominantly affects the lungs and lymph nodes but can also affect other systems of the body. Tuberculosis is spread by coming into direct contact with an infected person. It is becoming more prevalent due to reduced rates of immunisation. It is a potentially life threatening condition with a 50% chance of mortality if left untreated.It is estimated that up to 1/3 of the world’s population are affected. Not everyone who becomes infected develops symptoms so they can pass on the disease to other people without knowing. Signs and symptoms of active tuberculosis include coughing, blood in mucous, fatigue, weight loss, fever, chest pain and shortness of breath. Other signs and symptoms may arise if other organs of the body are affected. The main treatment is with antibiotics but incorrect treatment regimens have led to a rise in resistant strains which do not respond to antibiotics. This means that several different types of antibiotics may need to be prescribed in order to be effective. The tuberculosis vaccine is not currently part of the National Immunisation Schedule but is available as a travel vaccine and should be taken by anyone travelling to developing countries who is not already immunised. 9.1.6WHOOPING COUGHWhooping cough is also known as pertussis and is caused by the bacteria bordetella pertussis. It is highly contagious and is most dangerous in babies under 12 months of age. Babies under 4 months who have not had both their initial doses of vaccine are most at risk because they do not receive immunity from the mother. Signs and symptoms take 7-20 days to appear. There are two stages to the infection:Catarrhal stage - resembles the common cold with nasal congestion, sneezing, nasal discharge, conjunctivitis and mild fever. Paroxysmal stage – dry hacking cough that becomes paroxysmal (spasmodic) as it develops. Uninterrupted, spasmodic coughing until the patient runs out of breathing, followed by “whooping” as they draw in breath through constricted airways.Episodes of coughing can happen up to once an hour and the patient may vomit after coughing. They may develop cyanosis because of the lack of oxygen. In extreme cases, brain damage and even death can occur from lack of oxygen.Pertussis is especially dangerous in young children because oxygen deprivation can affect brain development.Whooping cough is treated by antibiotics. Oxygen may need to be administered to treat cyanosis.The best treatment is vaccination to prevent the disease in the first place. It is part of the National Immunisation Schedule for all babies and children in Australia.9.2CHRONIC OBSTRUCTIVE PULMONARY DISEASEChronic obstructive pulmonary disease (COPD) is the name given to a group of chronic respiratory conditions which involve obstructed or limited air flow. The main conditions included in this group are:EmphysemaChronic bronchitisAsthma 318135057785009.2.1EMPHYSEMAEmphysema is a condition characterised by destruction and loss of elasticity of the walls of the alveoli which results in reduced gas exchange between the lungs and the blood. There are about 300 million alveoli in the lungs. These are delicate, thin walled structures which are designed to maximise the available surface area for exchange of oxygen and carbohydrate between the lungs and the alveolar capillaries.Particles which are inhaled together with the air we breathe can irritate the alveoli causing inflammation leading to a build-up of mucous which reduces the amount of space available for air. As the irritation continues it eventually breaks down the delicate walls of the alveoli and they merge together to form bigger structures called bullae. It also causes the development of inelastic, fibrous scar tissue. The loss of elasticity means that the lungs do not contract properly on exhalation and carbon dioxide remains in the lungs. Passive exhalation ceases to be effectively and the patient must make a conscious effort to breathe out. Because the carbon dioxide has not been fully expelled, there is less space available for oxygen to be breathed in. About 80% of emphysema cases are due to cigarette smoking but it can be due to breathing in industrial or other pollutants. It can also arise from chronic pneumonia. Patients experience chest pain, shortness of breath, cough, wheezing, fatigue and exercise intolerance. Air trapped in the alveoli pushes out the lungs giving them a barrel-chested appearance. Emphysema cannot be reversed so prevention and early intervention is crucial. The first stage is to eliminate anything that can contribute to the condition – stopping smoking is key. Bronchodilators and mucous-reducing medications have limited effect on improving breathing. The patient may need oxygen therapy especially in the later stages. Surgery to remove damaged sections of lung by making more room for the remaining lungs but this is only suitable for a small number of patients.9.2.2CHRONIC BRONCHITISUnlike acute bronchitis, chronic bronchitis is not usually caused by infection.Chronic bronchitis is an inflammation of the bronchi and bronchioles caused by long term irritation due to smoking or pollutants in the air. 357187580327500The bronchi become inflamed and swollen which narrows the air passages. They also produce large quantities of mucus which fills the air passages and allows less air to pass through. Long term irritation can also lead to changes in the epithelium with a build-up of thick fibrous tissue. Chronic bronchitis manifests as a long term cough lasting 3 months or more which produces clear phlegm. The patient gets increasingly short of breath as the condition worsens. They may develop cyanosis and right-sided heart failure as a result of oxygen deprivation. The inability to clear mucous means that the patient is more susceptible to developing bacterial or viral respiratory tract infections and pneumonia.Treatment involves slowing the progress of the disease by quitting smoking and avoiding polluted air. Bronchodilators can make breathing easier. Most chronic bronchitis sufferers do not require oxygen on a regular basis but may need it in emergencies.People with chronic bronchitis should receive annual vaccinations against influenza and pneumococcus (a cause of bacterial pneumonia) because they are at increased risk of infection. 9.2.3ASTHMAAsthma is a chronic condition characterised by spasmodic tightening of the smooth muscle of the bronchi together with inflammation and increased mucous production. This results in constriction and blocking of the airways making it difficult to breath out. Unlike the other forms of COPD asthma rarely does permanent damage to the lungs. There are a number of reasons why people develop asthma. Allergic and exercise-induced asthma are developed in childhood while other forms may develop as a result of respiratory infection or cigarette smoking. Asthma often runs in families and can accompany other hypersensitivity disorders like hayfever and eczema.Once a person has developed asthma, it often remains with them for life. The main triggers of an asthma attack are:AllergensMedicationsAir pollutionIndustrial chemicalsRespiratory infectionsExerciseEmotional stressFeatures of an attack are:Shortness of breathCoughingWheezingRapid heart rateOver-inflation of lungsChest painCyanosis A severe attack of asthma can be fatal due to lack of oxygen. Most sufferers will carry medication with them, usually in the form of an inhaler, and this should be administered immediately. Where possible the patient’s own inhaler should be used as some patients are allergic to certain medications. For a severe attack, medical help should be sought straight away. Ongoing treatment is aimed at reducing the frequency and severity of attacks. This involves:Avoidance of allergens and pollutantsModifying exerciseAnnual influenza vaccinationPreventative bronchodilatorsCorticosteroids Relaxation techniques9.3ENVIRONMENTAL LUNG DISEASEThe main class of environmental lung diseases is pneumoconiosis. These diseases are caused by inhalation of organic or inorganic dust and are often workplace-related. They include:AsbestosisTalcosisCoal miner’s lungFarmer’s lungPsittacosis (bird fancier’s lung)AsbestosisThis condition is one of the more common forms of pneumoconiosis due to the amount of asbestos around us. It is found in people who have worked in asbestos manufacturing, installation and removal. It can also be found in other people who have had exposure for example people living in fibro houses made from asbestos sheeting. It is important to check carefully for asbestos before embarking on any home renovations. A license is now required to handle asbestos even in the home. Asbestosis is not a type of lung cancer, but it creates a significant risk of developing cancer, particularly mesothelioma, which we will look at later in this chapter.TalcosisTalcosis can be found in people who have inhaled large amounts of talcum powder. This can include manufacturing workers. Drug users may suffer from this because drug dealers use talc to dilute the drugs that they are selling. Other groups at risk include babies and small children who may accidentally inhale baby powder. Beauty therapists and pedicurists are also at risk of exposure if they use powder in their treatments.Coal Miner’s LungThis is common in many areas of New South Wales and Australia due to the mining industry. Underground mine workers are particularly susceptible to inhaling coal dust. Areas with a high incidence of this disease include the Illawarra and Hunter regions. Farmer’s Lung and PsittacosisBoth these conditions can be experienced by farmers. Farmer’s lung comes from inhaling hay dust while psittacosis comes from inhaling bird droppings including chickens.Manifestations and TreatmentSome types of pneumoconiosis, particularly those involving organic dust, trigger a type III hypersensitivity disorder resembling an asthma attack, with spasmodic constriction of the bronchi, inflammation and increased mucous. Chronic inflammation of the lungs often builds up with prolonged exposure. Inorganic dust leads to inflammatory lesions within the lungs with progressive fibrosis which leads to a loss of plications of pneumoconiosis are pneumonia from secondary bacterial and viral infections and the development of lung cancer.Treatment involves identifying and removing the cause where possible. Corticosteroids can be used to reduce inflammation and oxygen therapy may be needed in the later stages of the disease.9.4LUNG CANCERLung cancer is strongly linked to tobacco smoking, with bout 80-90% of lung cancers being smoking related. Other risk factors include exposure to industrial chemicals, asbestos, radiation or tuberculosis.About 95% of all lung cancers are carcinomas, with a low incidence of a number of other types of cancer. Nearly all lung cancers are carcinomas. There are two main types of lung carcinoma with important differences:Small cell carcinoma accounts for 25% of all lung cancers. It spreads quickly and easily metastasises to other areas of the body. It is rarely operable and survival time is usually less than five years.Non-small cell carcinoma accounts for the other 75% of lung cancers. It spreads slowly but often remains asymptomatic until they have already spread extensively. Less than 30% of patients will survive more than 5 years, mainly due to late detection.Signs and symptoms include a persistent cough, bloody phlegm, chest pain and shortness of breath. These all mimic other lung diseases which is why lung cancer is often not discovered until it is too late.Mesothelioma is a cancer of the lining of the pleural cavity surrounding the lungs. It is usually a result of long term asbestos exposure. It is much rarer than carcinoma which can also be asbestos-related. The symptoms are chest pain and difficulty breathing. Survival time is usually less than 2 years from diagnosis. Treatments for lung cancer include surgery, chemotherapy and radiation therapy. Sadly, even with these treatments, the prognosis for survival is poor.9.5CYSTIC FIBROSISCystic fibrosis is a genetically inherited condition which affects mainly the respiratory and digestive systems. It is an autosomal recessive disorder which means the child must inherit the defective gene from both parents in order to develop the disease.Cystic fibrosis inhibits the ability of chloride to pass through the membrane of epithelial cells. You will remember from anatomy & physiology that epithelial tissue makes up the skin and the mucous membranes of the body. Since chloride is almost always linked to sodium in the body, this also affects the absorption of sodium and therefore water which is attracted to the sodium. The significance of this is that the mucous produced by the membranes is abnormally thick in both the respiratory and digestive systems. It is difficult to clear the thick mucous out of the lungs which leads to obstruction of the airways and increased risk of respiratory infections. Many patients also have decreased pancreatic function which affects the ability to digest and absorb nutrients while males are often infertile. They also excrete excess sodium in sweat and are prone to dehydration in hot weather.There is no cure for cystic fibrosis so treatment focuses on managing symptoms. Respiratory symptoms are managed by antibiotics to prevent infections, mucolytic agents to break down the thick mucous and physical therapy to move mucous out of the lungs. Some people may receive a lung transplant.Pancreatic enzymes and vitamin and mineral supplements are used to manage gastrointestinal absorption issues.Life expectancy has improved but most will still die before the age of 40.LESSON 10 – CARDIOVASCULAR DISORDERS10.1Circulatory Conditions 10.1.1Hypertension10.1.2Postural Hypotension10.1.3Raynaud’s Disease/Phenomenon10.2Blood Vessel Disorders10.2.1Atherosclerosis10.2.2Varicose Veins10.2.3Deep Vein Thrombosis10.2.4Aneurism10.2.5Stroke10.3Heart Conditions 10.3.1Heart Attack10.3.2Angina10.3.3Heart Failure10.3.4Coronary Artery Disease10.3.5Arrhythmias 10.1CirculationThe heart pumps blood around the body to provide vital nutrients and oxygen to the tissues. You will have learned in anatomy and physiology that it is important to keep blood pressure within a certain range. Too little, and the tissues will not get the oxygen and nutrients they need. Too much, and the strain on the heart becomes too much.Blood pressure is divided into:Systolic - the amount of pressure when the heart muscles contract to pump the bloodDiastolic - the amount of pressure when the heart muscles are relaxed.When reading blood pressure, the systolic figure is always given first. Ideally, blood pressure should be at or below 120/80.SystolicDiastolicNormal<120<80Pre-hypertensive120-14080-90Stage 1 Hypertension140-16090-100Stage 2 Hypertension>160>100The diastolic pressure, which is the pressure when the heart muscle is relaxed, is a better indication of health.10.1.1HYPERTENSIONHigh blood pressure is known as hypertension. It is defined as a blood pressure greater than 140/90. Hypertension is one of the most common diseases in our society due mainly to modern diet and lifestyle. Hypertension puts pressure on the heart and blood vessels increasing risks of other diseases. It is known as the ‘silent killer’ because a person can easily have it without any signs or symptoms. Causes and risk factors for developing hypertension include:Family historyHigh salt intakeObesityLack of exerciseStressAlcohol consumptionCigarette smokingHigh cholesterolAtherosclerosis (hardening of the arteries)MedicationsKidney disease. There are few signs and symptoms, however some that may occur include headaches, exercise intolerance, swollen ankles and excessive sweating or anxiety. High blood pressure is important to get treated because it can lead to many complications including stroke, angina, heart failure, kidney disease and vision problems. The primary treatment for hypertension is lifestyle modification – losing weight, exercising regularly, reducing salt and alcohol consumption and stopping smoking. There are a number of different medications which can be prescribed to lower blood pressure. These include diuretics, beta-blockers (reduce heart rate and cardiac output) and ACE inhibitors (inhibit fluid retention and encourage vasodilation).Any patient on hypertensive drugs needs to be monitored closely by their doctor. Hypertensive medications can interact with other medications including herbal medicines, so it is important to consult with their doctor before prescribing anything.10.1.2POSTURAL HYPOTENSIONPostural hypotension is also known at orthostatic hypotension. It is defined as a sudden drop in blood pressure when a person changes position from lying to sitting or sitting to standing.When a person shifts from a lying/sitting position to standing, blood drains quickly to the legs which decreases blood pressure in the upper body and head. The body responds to this by constricting blood vessels and raising the heart rate to normalise the blood pressure. Postural hypotension is caused by a delayed reaction which results in low blood supply to the brain.Signs and symptoms include dizziness, weakness, nausea, blurred vision, palpitations and fainting. Symptoms usually last a few minutes until the blood pressure returns to normal.Postural hypotension is especially common in elderly people because they have lower cardiac output. Other risk factors include reduced blood volume, dehydration, bed rest or immobility and drug-induced hypotension. It can be side effect of medication to control high blood pressure. Treatment centres around resolving the cause of the condition. People on anti-hypertensive medications should have their medications reviewed. Diuretics should be avoided, as should dehydration and alcohol. Support stockings may help prevent pooling of blood in the legs.The person can also be taught ways of coping with the condition – such as taking their time to stand up. Moving the legs before standing helps to use the skeletal muscles as a pump to redistribute blood. lefttop10.1.3RAYNAUD’S DISEASE/PHENOMENONRaynaud’s disease and Raynaud’s phenomenon are two related conditions which result in a lack of blood flow to the extremities. 473392578105000Both conditions are characterised by a sudden vasoconstriction of the peripheral arterioles leading to a loss of blood supply to the hands and feet. Fingers and toes will turn white then blue. Attacks can last from a few minutes to a few hours and are usually triggered by cold or emotional stress. The difference between the two conditions is the underlying cause:Raynaud’s disease – the cause is unknown. Raynaud’s phenomenon – caused by some previous trauma including frostbite, vibration from using industrial machinery, collagen diseases, neurological disorders, arterial disease or occupational exposure to alternating hot/cold temperatures.Treatment is aimed at preventing attacks. This includes avoiding cold, anxiety, emotional distress and medications that can cause vasoconstriction. Lifestyle factors such as smoking which can affect peripheral circulation should also be avoided.10.2BLOOD VESSEL DISORDERSBlood vessel disorders affect our arteries, veins and capillaries which carry our blood around the body.10.2.1ATHEROSCLEROSIS345757513208000Arteriosclerosis is the name given to hardening of the arteries. Atherosclerosis is a type of arteriosclerosis caused by a build-up of fibrolipid lesions called atheromatous plaques on the inside of the arteries. The exact way in which the plaques developed is not fully understood. The plaques are white or yellow in colour and 0.5-1.5 cm in diameter but can join together to form larger plaques. As they form on the inside of the arteries they narrow the diameter. This leads to higher blood pressure and also means that the heart has to work harder to push the blood through the narrow space. As the plaques develop they can become calcified which can make the arteries brittle. The plaques can rupture or ulcerate leading to the development of a thrombus (clot) which can break off to form an embolus (a free moving object) which can then lodge somewhere else.Sometimes the plaques can grow enough to completely block an artery which can lead to ischaemia – where lack of blood supply can lead to tissue death. Complications from this can include gangrene in the legs or a heart attack depending on which arteries are blocked.Atherosclerosis often goes unnoticed. Until complications occur, the only symptom is raised blood pressure. As the condition develops, signs of ischaemia may become apparent in areas of the body affected by a loss of blood supply.Risk factors to developing atherosclerosis include high cholesterol levels, hypertension, cigarette smoking, diabetes, obesity, age, sex (males more at risk) and genetic factors.The progress of the disease can be slowed by lifestyle changes – losing weight, reducing cholesterol, stop smoking and exercise. Cholesterol lowering and blood thinning medications may be prescribed. Surgical interventions include a bypass of blocked blood vessels or placing a stent in the blood vessel to allow blood to flow through. Both of these are used when coronary arteries become blocked.10.2.2VARICOSE VEINS44577008191500Varicose veins are dilated, tortuous veins which are caused by failure of the valves due to increased pressure. They are mainly found in the legs because gravity puts the veins of the legs under greater pressure but they can be found anywhere. Veins in the legs appear ropey, twisted and are often a blue colour. Normally the valves prevent the backflow of blood due to gravity but when the valves fail the blood is able to flow back down causing a pooling effect. 445643033401000The veins may become tender and the person may develop aching and oedema in their legs after standing which improves if they elevate the legs.Risk factors for developing varicose veins include:Prolonged periods of standingPregnancy (foetus puts pressure on femoral vein)AgeSex (women are more likely)Congenitally weak veinsPhysical obstruction to blood flowObesityTreatment focusses on improving venous blood flow and preventing further damage. The patient can wear support stockings – which they should put on in the morning before the blood has built up. They should also elevate the legs at the end of the day.In some cases it is possible to perform surgery to remove damaged sections of veins. The body is very good at developing new blood vessels and can often generate new vessels to replace what has been removed.Although varicose veins are usually just unsightly and uncomfortable they can develop some complications. The most serious are blood clots which can then enter the circulation and lodge elsewhere blocking blood vessels, and varicose ulcers which occur due to lack of blood supply to the skin. 46520101587500010.2.4ANEURYSMAn aneurysm is an abnormal bulging in a blood vessel, most commonly found in the aorta or the brain. They are caused by a weakness in the smooth muscle that forms the wall of the blood vessel.Aneurysms can develop due to a number of factors including congenital weakness, trauma, infection, hypertension and atherosclerosis. Aneurysms are usually asymptomatic and most people do not realise that they have one until it ruptures. Large aneurysms over 4cm in diameter may cause pain.A ruptured aneurysm is often a life-threatening event. A ruptured aorta can cause severe loss of blood into the body and must be treated immediately. A ruptured aneurysm into the brain can cause a stroke. Aneurysms which are discovered prior to rupture are treated with surgery to mend the damaged blood vessel.10.2.5STROKEA stroke is also known as a cerebral vascular accident (CVA).A stroke is defined as a severe neurological deficit from vascular-related damage to the brain tissue. There are two types of stroke:Ischaemic stroke – interruption to blood supply through obstruction of a blood vessel, about 85% of all strokes. Due to a thrombus (clot) or embolus (dislodged material) in the blood vessel.Haemorrhagic stroke – bleeding into the brain from a ruptured blood vessel. Due to hypertension, aneurysm or weakened blood vessel.While ischaemic strokes are more common, haemorrhagic strokes are more likely to be fatal.The risk factors for developing a stroke are:HypertensionAneurysmDiabetesSmokingCardiac arrhythmiaAlcohol consumptionTumourBlood clotting disordersDrugs and medicationsIt is important to recognise the signs and symptoms of a stroke as prompt treatment can often save a life or prevent brain damage. The common signs and symptoms are:Severe, sudden headacheWeakness or paralysis on one sideDrooping faceLoss of visionLoss of balance and coordinationSlurred speechUnconsciousnessImmediate emergency treatment is needed. The type of treatment depends on the type of stroke. An ischaemic stroke will be treated with medications to dissolve the clot while haemorrhagic stroke requires immediate surgery to stop the bleeding.Following the stroke the patient will need ongoing physical therapy, speech therapy and other assistance to deal with the long term effects of brain damage. People at risk of a further ischaemic stroke may be prescribed blood thinning medication.People who are at high risk of a stroke should focus on prevention by moderating their lifestyle and managing hypertension or other health issues that increase the risk.Transient Ischaemic Attack (TIA)A TIA is similar to a stroke but there is no permanent damage. A small clot temporarily lodges in a blood vessel causing short term ischaemia. The signs and symptoms are the same as for a stroke but the person will recover fully.Having a TIA puts a person at high risk for a stroke. They may need to take blood thinning medication and implement lifestyle changes to prevent any further clots from developing and lodging in the brain.10.3HEART CONDITIONSOur heart pumps blood round the body providing essential nutrients and oxygen to all the cells and tissues. Without a functioning heart, all of our tissues and organs will die from starvation and oxygen deprivation. 10.3.1HEART ATTACKA heart attack is the death of part or all of the heart muscle due to ischaemia. Ischaemia is a lack of oxygen to the tissues due to an interruption to the blood supply. The resulting tissue death is known as infarction.There is an important difference between a heart attack and cardiac arrest.Heart attack – death of muscle tissue due to oxygen deprivation. The heart may or may not stop completely.Cardiac arrest – the heart stops beating. This can be due to heart attack or other causes.Heart attacks are usually caused by atherosclerosis of the coronary arteries. The fatty plaques that build up on the inside of the arteries obstruct the blood flow. Clots that form in the plaques can also block the arteries. When the blood cannot get through, the heart muscles do not get the vital oxygen and nutrients that they need to keep operating.The seriousness of the heart attack is determined by the size and location of the blockage and the length of time that the blockage lasts.Time is a key factor in heart attacks. The heart muscle loses its ability to contract within about 60 seconds. Within a few minutes, the cells begin to swell and cease functioning. Irreversible cell death (necrosis) happens within 20-40 minutes. After this, the damaged portion of the heart will not recover.It is important to recognise the signs and symptoms of a heart attack so that emergency medical attention can be received as soon as possible. They are:Chest painPain radiating to left arm, neck or jawProlonged pain not alleviated by restCrushing or constricting feeling in chestShortness of breathNauseaAnxietyPale, clammy skinShock Loss of consciousness The risk factors for having a heart attack are similar to those for other diseases of our society – obesity, lack of exercise, diabetes, hypertension, smoking and stress.Treatment needs to be commenced as soon as possible. Common treatments for a heart attack include:Administering oxygenAspiringBlood-thinning medicationsNitroglycerin (vasodilator)Pain medicationsThrombolytic agents (break down clots)Beta-blockers (block sympathetic nervous system and reduce oxygen needs of heart muscles) There are a number of surgical treatments available. Surgery involves removing damaged tissues and preventing further attacks. Surgical techniques include:Coronary stent – placing a small tube inside the blood vessel to keep it openAtherectomy –surgically removing the atherosclerotic plaqueCoronary artery bypass – grafting a new section of blood vessel that by-passes the blocked section. (usually uses section of blood vessel taken from the leg).Rehabilitation programs after a heart attack involve lifestyle modification including diet, appropriate exercise, stopping smoking, stress management, control of hypertension and diabetes. 10.3.2ANGINAUnlike a heart attack, angina does not result in the permanent death of heart muscle tissue.Angina is a pain in the chest which is triggered by exercise or physical activity and is relieved by rest. It happens when a partial obstruction of the coronary arteries results in restricted blood flow. This means that the muscles do not get enough oxygen. The effect is similar to getting pain from lactic acid in your legs if you run too hard. The causes of angina are similar to those of atherosclerosis or a heart attack – obesity, diabetes, hypertension, lack of exercise, smoking. Signs and symptoms are also similar to those of a heart attack, except that they are usually less severe and can be alleviated with rest. Note - if the symptoms do not go away with rest, there is a good chance that the person is having a heart attack so they should receive medical attention as soon as possible.Many people who are diagnosed with angina have medication that they can take if they experience an attack. This is usually either nitroglycerin which dilates the blood vessels or beta-blockers which reduce the heart rate.While angina is different to a heart attack, it is a good warning sign that a heart attack may occur in the future. People with angina should modify their lifestyle including diet and exercise to reduce the risk.10.3.3HEART FAILUREThe amount of blood that the heart is able to pump round the body in a given time is known as the cardiac output. As with all muscles, the cardiac output is determined by strength and fitness. Endurance athletes have strong hearts due to conditioning and their cardiac output on exercising may be 5-6 times what it is at rest. On the other hand, someone with heart failure may use all of their cardiac output even when they are resting. For these people even the slightest activity such as climbing a flight of stairs can leave them breathless.Heart failure is a progressive loss of cardiac output due to age or history of cardiovascular disease. The heart loses its ability to pump the blood round the body at a sufficient rate to meet the oxygen and nutrient requirements of the cells and tissues. Heart failure does not mean that the heart has stopped – that is cardiac arrest.Heart failure can be:Systolic – the heart muscle loses its contractibility – that is, the ability to contract and push the blood round the systemDiastolic – the heart loses its elasticity – that is, its ability to stretch and allow the chambers of the heart to fill up with blood which can then be pumped.Causes of heart failure are similar to those of other cardiovascular diseases – hypertension, atherosclerosis, diabetes, obesity, smoking, stress and lack of exercise. Previous cardiac injury from angina or heart attack can also cause changes to the heart muscles.335280058293000Heart failure is often caused by cardiac hypertrophy. When the heart has to work extra hard – for example when the patient has hypertension or atherosclerosis – the heart muscles adapt by growing to become stronger. The problem with this is that the hypertrophied muscle means that there is less space within the heart for blood. The hypertrophied muscle is also less flexible, just like many bodybuilders have limited flexibility. The reduced flexibility together with reduced capacity of the heart chambers means that less blood is pumped round the body with each contraction of the heart muscle.Sometimes the heart muscles will become irreversibly stretched – they lose their elasticity, remaining dilated, and cannot contract to pump blood. This is due to increased pressure from hypertension.Damage to the heart from episodes of angina, heart attack or other injury can cause fibrosis – the development of fibrous scar tissue to replace the damaged heart tissues. Scar tissue is formed from fibrous collagen and is less flexible than muscle tissue which reduces the heart’s ability to contract and pump blood. The manifestations of heart failure depend on whether the right or left side of the heart is affected. The left side is more commonly affected than the right. Right-sided failure often happens at the same time as left, so there will be both sets of symptoms. Treatment often centres around lifestyle modifications to reduce the stress on the heart. This includes rest, dietary changes and changes to physical activity. Medications for heart failure include beta-blockers to reduce heart rate, diuretics and vasodilators to reduce blood pressure.In some cases surgical treatments may be appropriate. This could include repair to damaged valves or artificial pumps to decrease the workload of the heart. In extreme cases, the patient may receive a heart transplant.Oxygen therapy is often required in advanced heart failure.10.3.4CORONARY ARTERY DISEASECoronary artery disease (CAD) is a condition which involves impaired blood flow to the heart muscles due to an obstruction of one or more of the coronary arteries. This is usually due to atherosclerosis.Causes of CAD are the same as for atherosclerosis elsewhere in the body - high cholesterol levels, hypertension, cigarette smoking, diabetes, obesity, age, sex (males more at risk) and genetic factors. CAD often remains asymptomatic until it is in advanced stages because, as the large blood vessels become blocked, the smaller ones take over. As the disease becomes more advanced, less blood is able to reach the heart muscles. As this happens, exercise intolerance increases. The patient will also suffer the effects of ischaemia on the heart muscles – angina and possible heart attack.Treatment focusses on lifestyle modification to slow the progress of the disease. This includes managing hypertension, losing weight, appropriate exercise and stopping smoking. The patient may be given blood-thinning medication. They may also be given medication such as nitroglycerin and beta-blockers to be taken in the event of an angina attack.In some cases surgery may be performed to insert a stent into the blocked artery which allows blood to pass through. Another type of surgery is a cardiac bypass which involves removing the blocked section of artery and bypassing it with a new section of blood vessel.10.3.5ARRHYTHMIASCardiac arrhythmias are disruptions in the normal rhythm of the heart.Heart rhythm is created by the sinoatrial node (SA node) which is the natural pacemaker of the heart. The SA node sends out electrical impulses which stimulate the muscles of the atria to contract. This signal is then transmitted from the atria to the ventricles via the atrioventricular node (AV node). Dysfunction of either of these nodes can cause an abnormal heart rhythm called an arrhythmia.Arrhythmias can be congenital – something we are born with – or acquired.There are many different types of arrhythmia. Some of the common ones are summarised in the following table.ConditionEffectsCauseSinus BradycardiaSlow heart beat <60bpmAthletesHyperkalaemia (excess potassium)HypoxiaSinus TachycardiaFast heart beat >100bpmExercise stressFeverHeart failureSupraventricular TachycardiaFast heart beat 140-240bpmSudden, short term attackSensation of palpitationsShortness of breathCongenital abnormalityAtrial FibrillationErratic heart beats up to 400 bpmHeart beat too fast to allow atrial and ventricular fillingCoronary artery diseaseHypertensionHeart attackHyperthyroidismPremature Ventricular ContractionsEctopic (extra) heartbeatHeart diseaseInfectionSympathetic nervous systemElectrolyte disturbanceMedicationsVentricular FibrillationHeart rate >350bpmVentricles pulsate but do not contract.Heart attackTreatmentTreatment is aimed at controlling the arrhythmia, correcting the cause where possible, and preventing serious consequences.Some arrhythmias can be treated with something as simple as correcting an electrolyte disturbance. There are also various types of medication which can control the electrical impulses which create the arrhythmia, which work in a number of different ways.Pacemakers can be fitted which transmit an electrical pulse that overrides the heart’s own electrical signals and creates a steady rhythm. Defibrillators can also be fitted which automatically activate in the event of atrial or ventricular fibrillation.LESSON 11 – BLOOD DISORDERS11.1Anaemia 11.2Hypercoagulability11.3Bleeding Disorders11.4Leukopenia 11.5Leukaemia11.1ANAEMIAAnaemia is a reduced capacity of the blood to carry oxygen round the body due to:A lack of red blood cellsorA lack of haemoglobinA lack of red blood cells can either be due to bleeding through trauma or due to a condition which causes red blood cells to break down at a faster rate than normal.Anaemia can also be due to deficient red blood cell or haemoglobin production. This is often due to nutritional deficiencies including iron, vitamin B12 and folate.Iron Deficiency AnaemiaIron deficiency anaemia is the most common form of anaemia and affects people of all ages. Iron is a major component of haem, the component of red blood cells which carries oxygen round the body. Without iron, the oxygen carrying capacity of the cells is diminished.Iron is lost through dietary deficiency, bleeding or increased demands. Iron is used continuously. As red blood cells break down the iron is released and used to make new blood cells but a small amount is lost each time in faeces. We need to make up this loss by dietary intake.The western diet contains enough for most people but children require more because they are growing, and menstruating women also need more because of blood loss.Most dietary iron comes from red meat. Iron can also be obtained from plant sources but it is present in lower amounts and is also less bioavailable – meaning that we are able to absorb a smaller percentage of the available iron. Plant-based iron is also in a different form which can be used less efficiently. Some iron-rich foods also contain other minerals which prevent the absorption of iron. An example of this is spinach which contains phytate fibre which inhibits iron absorption.Megaloblastic AnaemiaMegaloblastic anaemia is caused by either a lack of vitamin B12 or a lack of folic acid. Usually this is due to a dietary deficiency but sometimes it can be caused by malabsorption.Vitamin B12 requires intrinsic factor, which is produced in the stomach, in order to be absorbed. Inability to produce intrinsic factor is called pernicious anaemia. People with pernicious anaemia will not be able to get vitamin B12 from normal dietary supplements. They may be able to take sublingual supplements (dissolve under the tongue) but it is more effective to have injections. Megaloblastic anaemia has one key difference to iron deficiency anaemia – the red blood cells are bigger than normal but they have a short life.Vitamin B12 is only found in animal products including meat, eggs and dairy. It is not available in any plant foods. Vegans are at risk of developing B12 deficiency but it can take several years to develop because the body is good at storing it. The only way to replace B12 without eating animal products is with supplements or injections.Folic acid is found in a wide range of food sources including meat and plant foods however much of it is lost in cooking. Many bread and cereal products are fortified with extra folate. Pregnant women are susceptible to folic acid deficiency because they have a higher than normal requirement.Manifestations and TreatmentThe signs and symptoms of anaemia are pallor, fatigue, exercise intolerance, brittle hair and nails and impaired cognitive function Some people may feel short of breath due to low oxygen levels. Confirmed diagnosis can be made with blood tests. The tests will show low haematocrit (number of red blood cells). Depending on the type of anaemia, the tests will also show low iron, low ferritin (the storage form of iron), low B12 or low folate.Anaemia is usually treated with dietary supplements. Those with severe anaemia can receive injections of iron or B12 depending on the cause of the anaemia. Controlling chronic blood loss – such as heavy menstruation or gastrointestinal bleeding – will also help to control the anaemia.11.2HYPERCOAGULABILITYHypercoagulability is a condition where the blood clots more easily than normal. This creates the risk that a thrombus (clot) will develop in a vein or artery and block the circulation.The two ways in which hypercoagulability can develop are through:Increased platelet functionIncreased clotting factorsIncreased platelets can occur as a result of other conditions including surgery, infection, cancer, rheumatoid arthritis and Crohn’s disease. Increased red blood cells can also lead to an increase in platelet production. This is why erythropoietin (EPO) is banned in competitive sport because it increases red blood cell production.Increased clotting factors can be due to a hereditary condition or as a result of other factors including bed rest, immobility, heart attack, cancer, smoking and contraceptives or hormone replacement therapy containing oestrogen.Hypercoagulability conditions are potentially dangerous because a clot could form in the lungs or heart which is potentially fatal. The condition should be managed with lifestyle changes to reduce the risk and blood thinning medication such as aspirin, warfarin or heparin.People at risk should avoid long periods of sitting or immobility as it is important to keep the circulation moving to prevent clots. Long distance and airline travel is a particular risk.Anyone who is on blood-thinning medication needs to be carefully monitored by their doctor. These medications also interact with a lot of other medicines including herbal medicines so it is important to consult with their doctor when prescribing anything.11.3BLEEDING DISORDERSBleeding disorders occur when a person bleeds too easily. This can be due to a lack of platelets, lack of clotting factors or weak blood vessels.Platelets can be reduced due to a destruction of bone marrow as in leukaemia. Some medications also reduce the number of platelets, including warfarin and heparin which are a common blood thinning medication used in the treatment of atherosclerosis.Another cause of excessive bleeding is a lack of clotting factors. This is the problem with people suffering from haemophilia who have a genetic condition which means they are lacking one of the clotting factors.Vitamin K is needed to produce clotting factors. It is a fat soluble vitamin which is synthesized in the intestines from a wide range of foods so it is very rare to be deficient. Newborn babies do not have vitamin K until they have started feeding so babies born in hospital are usually given an injection of vitamin K in case they bleed. Bleeding can also be caused by weakened blood vessels. This can be due to scurvy (lack of vitamin C), Cushing disease (excess cortisol) or old age. Other factors that can weaken blood vessels include viruses, bacterial infection, extreme temperature, snakebite, shock or trauma.Treatment for bleeding disorders is normally focussed on treating the underlying cause. This may mean a review of medications. People with haemophilia can receive transfusions of clotting factors. They should also avoid injury. 11.4LEUKOPENIALeukopenia is a lack of white blood cells. The most common type of leukopenia is neutropenia which is a lack of neutrophils.Neutrophils account for 60-70% of all white blood cells. Their primary role is to fight bacteria and fungi which they do through the process of phagocytosis (engulfing the pathogen in order to destroy it).There are a number of different causes of neutropenia:Autoimmune – some autoimmune conditions like rheumatoid arthritis and lupus produce antibodies to neutrophilsInfection – viral or bacterial infections. Neutropenia is one of the main symptoms of AIDS.Medications – chemotherapy and some antibiotics can destroy suppress the production of white blood cells in the bone marrowRadiation – radiation therapy for cancer damages the bone marrow11.5LEUKAEMIALeukaemia is the name given to cancers of the bone marrow which lead to the development of abnormal blood cells. The abnormal cells do not function properly, have a long life span and interfere with the development of normal cells.Leukaemias are classified as to how fast they develop and what type of cells are affected. There are four types all together:Acute – develop and spread rapidlyChronic – develop slowlyMyelogenous – affect granulocytes and monocytesLymphocytic – affect lymphocytesThe manifestations of leukaemia are:AnaemiaFatigueAbnormal bleeding – bruising easily, bleeding gumsBone painHeadacheAbdominal pain, nausea, vomitingIncreased susceptibility to infectionThe causes of leukaemia are largely unknown. There does appear to be a genetic component, with Down syndrome children being 10 times as likely to develop leukaemia. There is also an increased risk in patients who have previously received chemotherapy for other types of cancer.Because the malignant cells travel in the blood stream it is easy for them to migrate to other parts of the body and invade other tissues and organs.The main treatment for leukaemia is chemotherapy. This can actually make the symptoms worse because it kills bone marrow and blood cells.Bone marrow transplant can be considered for patients who do not respond to chemotherapy. This can be done either by taking a piece of healthy bone marrow from the patient or from a donor. The patient’s own bone marrow is then destroyed by chemotherapy before the healthy bone marrow is transplanted. Using bone marrow from a donor is risky because the patient will need to take anti-rejection medications, and there is still a chance that they will reject the donor marrow.LESSON 12 – IMMUNE SYSTEM DISORDERS12.1Hypersensitivity Disorders12.1.1Allergies12.1.2Delayed Response Hypersensitivities 12.2Systemic Lupus Erythematosus12.3Epstein-Barr Virus12.4Human Immunodeficiency Virus12.4.1Retroviruses12.4.2Transmission and Prevention12.4.3Stages of the Disease12.4.4Treatment12.5Lymphoma12.1ALLERGIESHypersensitivity reactions occur when a person has an excessive or inappropriate immune response to a substance which would normally be considered harmless. Substances which trigger these hypersensitivity responses are known as allergens.There are a number of different types of hypersensitivity response. The main kinds are:Allergies – immediate response within a few minutes of exposureDelayed response – can take hours or days to manifest, often with repeated exposure12.1.1ALLERGIESAn allergy is a type I hypersensitivity reaction also known as an IgE mediated reaction because the body reacts by fighting the allergen with immunoglobulin E (IgE), a type of antibody which triggers an immediate response.The IgE antibodies are released by B cells in the blood in response to the presence of an allergen. This then triggers mast cells (tissue cells) and basophils (white blood cells) to react and fight the allergen by producing an inflammatory response.Many different types of substances can provoke an allergic reaction. Common allergens include dust, mites, pollen, latex, nuts, fish and eggs. There are many other allergens – over 2,000 have been identified in total.Allergic reactions begin rapidly – often within a few minutes of contact with the allergen. There are two types of reaction:Atopic – a localised reaction e.g. skin irritation, rhinitis or asthmaAnaphylaxis – a systemic reaction that can be debilitating and even life threateningType I allergic reactions often have two phases. Initial phase - involves mast cells which release histamines into the local area. Histamines cause inflammation leading to the common signs and symptoms of hives, rhinitis and asthma. Secondary phase - inflammatory response which happens 2-8 hours after exposure and can last for several days. The second phase can cause tissue damage. It is unclear why allergies develop but there is often a family history. Allergies usually develop in childhood but can start at any age. Atopic ReactionsManifestations of allergic reactions depend on how the allergen enters the body. They are caused by the mast cells releasing histamines which then cause localised inflammation. They can include asthma, rhinitis, itchy eyes, sore throat or hives. Anaphylaxis Anaphylaxis is an acute, systemic response to an allergen that can be potentially life-threatening. In this case, large quantities of histamines get released into the blood and travel round the body.The large amounts of histamines cause widespread oedema, erythema (red skin), breathing difficulties and vasodilation. The vasodilation can cause a dramatic drop in blood pressure leading to shock.It is important to recognise the signs and symptoms of anaphylaxis because it can develop into a life-threatening emergency. They are:Skin erythemaItchingHivesBreathing difficultiesOedema of throatVomitingShockTreatmentPeople who know they have an allergy should avoid the allergen as much as possible. Some allergens like pollen are unavoidable in which case anti-histamine medications can reduce the response.Anaphylaxis needs to be treated quickly as the person may stop breathing. It is usually treated by an injection of adrenalin. The person may have their own supply if they know they are at risk. Injectors are often referred to by the brand name Epipen but there are also other brands available. 12.1.2DELAYED RESPONSE HYPERSENSITIVITIESNot all hypersensitivities result in an immediate allergic reaction. There are 3 other types – Types II, III and IV – which are mediated by IgG antibodies, T cells or a combination. Food intolerances (as opposed to food allergies) and contact dermatitis are both examples of delayed responses.It is often difficult to determine the cause of the response because it may not start until 24-48 hours after exposure and continue after exposure has ceased.Symptoms of food intolerances include:Gastrointestinal upsetMalabsorption of nutrientsDermatitisFatigueFood tolerances are usually diagnosed using an elimination diet. It is important to eliminate other factors including:Psychological factors (if someone believes they are intolerant, they will display symptoms)Reactions to excessive or inadequate consumption of a type of food (e.g. excess carbohydrates may cause bloating)Reactions to sudden changes in diet (e.g. sudden increase in fruit may cause a temporary reaction because the digestive system is not used to processing the additional fibre)12.2SYSTEMIC LUPUS ERYTHEMATOUSSystemic lupus erythematous (SLE) is a systemic autoimmune condition where antibodies attack various tissues throughout the body. The causes of SLE are unknown. There does not appear to be a genetic factor with only 5% of children of sufferers going on to develop the disease themselves. It is more prevalent in women than in men. The disease affects many different body systems so there is a wide range of signs and symptoms.Because of the number of body systems involved diagnosis can be complicated. The American College of Rheumatology have published a list of 11 criteria which are used for diagnosis, with at least 4 being present. The key diagnostic criterion is the presence of anti-nuclear antibodies in the blood which are present in over 90% of patients.Treatment for SLE is focussed on managing the signs and symptoms of the disease. This mainly involves anti-inflammatory medications and corticosteroids. In severe cases immunosuppressants may be used. Anti-malarial drugs have also proved useful for some of the skin rashes and ulcers.12.3EPSTEIN-BARR VIRUSEpstein-Barr virus (EBV) is also known as glandular fever or mononucleosis.EBV occurs in all age groups but is most common in children, adolescents and young adults. It is spread mainly through contact with oral secretions – hence the nickname “kissing disease” but it can also be spread through other means like sharing a glass of water. EBV has an incubation of up to 60 days before symptoms become apparent and a person can pass on the virus during this time without knowing.EPV initially infects the mucous membranes of the pharynx and the salivary glands. It then spreads to nearby lymphoid tissue including tonsils, adenoids and cervical lymph nodes where it infects the B cells. The infected B cells have an extended life span and also replicate themselves at a great rate. They produce lots of antibodies including antibodies to the virus and also another type of antibody called heterophiles. The presence of these antibodies is used in the test to see if someone has the virus. The body responds to the presence of infected B cells by producing large numbers of killer T cells which will eventually control the B cells until they become dormant in the epithelial cells of the throat. This can take a long time and active EBV virus can still be found in saliva several months after symptoms have cleared up.Severity of symptoms varies greatly between patients. Some may be almost asymptomatic while others will be severely debilitated for a long period of time. Initial feelings of general fatigue and malaise will generally be followed by fever, sore throat and swollen, painful cervical lymph nodes. The lymph nodes become swollen due to the large number of B and T cells. Other lymph nodes may become swollen to a lesser extent.Potential complications are inflammation of the spleen and liver. A less dangerous complication is streptococcal infection of the throat. EBV does not respond to antiviral medications so treatment is based on alleviating symptoms such as pain and fever, good nutrition and rest. 12.4HUMAN IMMUNODEFICIENCY VIRUSHuman immunodeficiency virus (HIV) is a viral infection that invades the immune cells of the body where it replicates and slowly destroys the immune system. When the immune system reaches a critical level the body is unable to defend itself against other opportunistic infections. This condition of having a critically weakened immune system is known at acquired immunodeficiency syndrome (AIDS).Once upon a time HIV was considered a death sentence. When the disease first emerged in the 1980’s it was like nothing that had been seen before. With no prevention measures in place, and no treatments developed, it spread quickly through at risk communities and killed most of the people infected within a few years.Nowadays it is a very different story. We know much more about HIV – what it is, how to avoid catching it and how to treat it. Infection rates in the developed world have decreased dramatically and there is a considerable increase in the expected lifespan of those who have been infected. Fear of the disease has also decreased as we understand more about how it can and cannot be transmitted, meaning that sufferers are no longer isolated from the community.HIV works by targeting the helper T cells of the immune system. These cells have a very important role to play. They activate the B cells which release antibodies to fight infection and the killer T cells which destroy infected cells.Because the virus hides itself so well inside the T cells, it goes unnoticed by the body’s immune system and is free to replicate itself without danger of being detected and destroyed.The virus replicates inside the T cell. The T cell then dies and ruptures which releases copies of the virus into the blood which are able to infect more T cells. This happens at a faster rate than healthy T cells can be produced so the T cell count begins to diminish. When it gets low enough the body is no longer able to fight off infection.12.4.1RETROVIRUSESHIV is a type of virus known as retrovirus. Most viruses are single-celled organisms containing a nucleus of DNA – this is what contains the genes that our cells need to replicate. Retroviruses on the other hand contain RNA. There is a slight difference. RNA is produced by our cells when they replicate. It is like a copy of DNA but with some minor changes. It then gets converted into a new piece of DNA when the cell replicates (you may learn more about this in advanced anatomy & physiology studies). When retroviruses invade a cell, they bring their own RNA with them. Once inside the host cell, they convert their RNA into DNA which is incorporated into the host cell. The host cell treats the viral DNA as part of its own and uses it to produce genes. This is how the virus produces new copies of itself. Retroviruses are very difficult to detect until they have invaded a host cell and infected it. By the time this happens it is too late to prevent it. 12.4.2TRANSMISSION AND PREVENTIONWhen HIV was first discovered there was a lot of panic because no-one really understood how it was transmitted. People were afraid that they could catch it simply from touching an infected person – or even by breathing in the same air.These days we know a lot better. HIV can only be transmitted in bodily fluids. It is actually quite fragile and cannot survive in the atmosphere. This means that you would have to get the body fluids of another person inside your body in order to catch it. This can happen either by ingestion or through an open wound. Common methods of transmission are sexual intercourse, blood-to-blood contact (as in sharing needles) or perinatally (from mother to baby).Sexual contact is the most common form of transmission with over 75% of infections occurring due to unprotected sex. The virus is present in both semen and vaginal fluid. Transmission in this way is easily preventable by the use of condoms. Sadly, in some parts of the world access to condoms is limited, or use of them is discouraged by religious or community leaders. People with other sexually transmitted diseases are higher risk of contracting HIV because they may have lesions which provide a way for the HIV virus to enter the blood stream.Because HIV is found in blood, a common form of transmission is by sharing needles and syringes with an infected person. This is common among drug users. Be careful when walking around barefoot in areas where drug use may occur like a park of beach. Standing on a needle is unlikely to cause infection because the virus dies in air, but if there is still liquid blood inside the needle it could enter your body. Needle exchange programs are aimed at reducing the risk of transmission of HIV and other diseases by providing sterile needles and syringes to drug users.Healthcare workers also need to be careful of needlestick injuries which should always be reported. The other method of transmission is from mother to baby. This can happen in utero (in the womb), during labour and delivery, or by breast-feeding. Over 90% of infected children catch the disease in this way. A person infected with HIV can transmit the disease even when they have no symptoms. It can take a few weeks to a few months for the disease to develop to the stage where it can be detected in a blood test and it is possible to transmit it during this time so anyone who thinks they may have been infected needs to have tests over a period of time to make sure they are clear and also need to take extra care not to infect other people during this time.12.4.3STAGES OF THE DISEASEThere are three phases to HIV:The American Centre for Disease Control and Prevention (CDC) and the World Health Organisation (WHO) have different ways of classifying the disease, according to the stage of development. Both systems begin with the latent phase, where T cell counts are still high and the patient is relatively asymptomatic, ending with overt AIDS where the T cell count falls too low to mount an immune response and the body becomes overwhelmed by infections.Both systems are used to determine appropriate treatment regimes.CDCThe CDC divides HIV/AIDS into 3 categories according to the number of remaining T cells in the body. The lower the T cell count, the more symptoms occur.Category 1 T cell count >500 cells/?lInitial acute viral symptoms (acute HIV)Largely symptomaticPersistent lymphadenopathy (inflammation of lymph nodes)Category 2 T cell count 200-500 cells/?lBeginnings of symptomatic conditionsCandidiasis (thrush)Pelvic inflammatory diseaseCervical cancerHerpes zoster (shingles)Idiopathic thrombocytopenic purpure (spontaneous bruising)FeverLong term diarrhoeaPeripheral neuropathyCategory 3T cell count <200 cells/?lAIDS-defining illnessesCandidiasisCervical councilCytomegalovirusEncephalopathyHerpes simplexKaposi sarcomaLymphomaTuberculosisPneumoniaSalmonella septicaemiaToxoplasmosis of brainWasting syndromeWHOThe WHO divides the progression of HIV/AIDS into primary infection followed by 4 stages of development. It bases the stages on the type of symptoms displayed rather than T cell count, making it easier to judge the progression of the disease in developing countries where it may be more difficult to process blood tests.Primary InfectionAcute HIVAsymptomaticClinical Stage 1 AsymptomaticPersistent lymphadenopathyClinical Stage 2Moderate unexplained weight lossRecurrent respiratory infectionsHerpes zosterOral ulcersSkin rashesFungal nail infectionsClinical Stage 3 Severe unexplained weight lossChronic diarrhoeaPersistent feverOral thrushTuberculosisSevere bacterial infectionAnaemiaLow plateletsNeutrophils <500 cells/?lClinical Stage 4Wasting syndromePneumoniaHerpes simplexCandidiasisTuberculosisKaposi sarcomaCytomegalovirusCNS toxoplasmosisEncephalopathySalmonellaLymphomaCarcinomaNephropathyCardiomyopathy12.4.4 TREATMENTThere is still no vaccine or cure for HIV. The virus mutates easily so it is very difficult to produce an effective vaccination.Treatment focuses on slowing the progress of the disease, alleviating symptoms of overt AIDS and preventing and treating opportunistic infections.Anti-Retroviral MedicationProgress of the disease can be slowed using highly active anti-retroviral therapy (HAART).Heart involves the administration of at least 3 different types of anti-retroviral medications. There are several types of anti-retroviral drugs which suppress the replication of the virus. Each type of medication acts at a different stage of the replication cycle which is why they work best in combination.Opportunistic InfectionsThe low T cell count means that patients are susceptible to opportunistic infections. These are infections that would not normally be able to take hold in a person with a strong immune system. The best treatment is prevention – avoiding situations where the person could pick up an infection. This includes staying away from friends and family who have an illness.Treatment of opportunistic infections depends on what the infection is. Palliative CarePalliative care is the end stage for people who are terminally ill and are not expected to improve. It consists of making the person as comfortable as possible in the final stages of their life. 12.5LYMPHOMALymphomas are a group of cancers which affect the lymphoid tissues. They are solid tumours arising in the lymph nodes involving a proliferation of abnormal B cells and T cells.Mutated cells within the lymph nodes replicate producing large masses of abnormal, non-functioning lymphocytes. As a result, the lymph nodes become enlarged. The enlarged lymph nodes are painless – this is the key difference between lymphoma and inflammation due to infection by pathogens. Swollen lymph nodes are found mainly in the cervical, axillial and inguinal nodes. Patients may also experience anaemia, fatigue, weight loss, night sweats, itchy skin and loss of appetite. In late stages the patient will have diminished immunity leading to secondary infections.The cause of lymphoma is often unknown but previous exposure to HIV or Epstein-Barr virus considerably increases the risk.Lymphoma is categorised into Hodgkin’s lymphoma and Non-Hodgkin’s lymphoma.Hodgkin’s LymphomaHodgkin’s lymphoma accounts for around 10% of all lymphoma cases. It results in abnormally large B cells, known as Reed-Steenberg cells, in a few lymph nodes, usually the cervical nodes. It has been linked to Epstein-Barr virus. It affects mainly adults in two age groups – 15-40 and over 55.Symptoms include a palpable mass in the neck, cough, fever, night sweats and weight loss. As the disease progresses, the patient will become more susceptible to secondary bacterial and viral infections.Hodgkin’s lymphoma is capable of metastasising to other organs including liver and bone marrow. Hodgkin’s lymphoma is treated with radiation therapy and chemotherapy. With timely detection the survival rate is better than 85%.Non-Hodgkin’s LymphomaThere are a number of sub-types of non-Hodgkin’s lymphoma which together account for around 90% of lymphomas.The non-Hodgkin’s lymphomas are diverse, affecting both B cells and T cells and can be present in any age group. Most of them affect lymphoid tissues throughout the body, which is different from Hodgkin’s lymphoma that only affects a few lymph nodes. The causes of non-Hodgkin’s lymphomas are largely unknown.The manifestations of the lymphoma depend on the type of lymphoma and the stage of development. Slow-growing lymphomas can remain relatively asymptomatic apart from enlarged, painless lymph nodes. Aggressive or more developed lymphomas present with fevers, night sweats or weight loss. They can also result in secondary infections including bacterial, viral and fungal infections.Treatment of non-Hodgkin’s lymphomas depends on the type and stage of development of the disease. Lymphomas that are limited to a single lymph node or group of nodes can be treated with radiation therapy but many are widespread throughout the body and require chemotherapy.The prognosis depends on the type and extent of the lymphoma but is generally around 60-80% recovery.LESSON 13 – DIGESTIVE DISORDERS13.1Gastroesophageal Reflux Disease13.2Peptic Ulcers13.3Gastroenteritis13.4Irritable Bowel Syndrome13.5Inflammatory Bowel Disease13.5.1Crohn’s Disease13.5.2Ulcerative Colitis13.6Appendicitis13.7 Bowel Cancer13.8 Liver Cirrhosis13.9 Hepatitis13.10 Jaundice13.11 Gallstones13.1GASTROESOPHAGEAL REFLUX DISEASE Gastroesophageal reflux disease is also known as GORD or GERD. It is colloquially referred to as heartburn.It is a condition where the lower oesophageal sphincter (between the oesophagus and the stomach) is weakened, allowing acid to regurgitate from the stomach back up into the oesophagus. Unlike the stomach, the oesophagus does not have the thick layer of protective mucous that protects it from corrosion by the acid. This leads to chronic irritation. There are several possible complications arising from this:Respiratory injury – acid reaches the larynx causing injury. Inflammation of the oesophagus can also spread to the tracheaOesophageal ulcers – risk of infection or bleedingStricture – formation of fibrous scar tissue which is inflexible and restricts the oesophagus making swallowing difficultBarrett’s oesophagus – development of abnormal cells which is a precursor to oesophageal cancerRisk factors for developing GORD include:Pregnancy – the growing foetus puts pressure on the abdomen pushing stomach contents upwardsObesity – fat accumulations around abdominal organs creates pressureDiet – diet high in fatty or spicy foods, caffeine, alcohol and acidic foods can also increase the acidity of the stomach and exacerbate the conditionAutoimmune diseases – inflammatory conditions can cause inflammation of the sphincter which weaken itHiatal hernia – part of the stomach pushes through the hiatus of the diaphragmDelayed gastric emptying – conditions which slow down rate of emptying from stomach to small intestine can cause pressureGastric banding – reduced stomach capacity increases pressure within the remaining stomachMedications – some medications increase riskThe main symptom of GORD is heartburn – a severe pain in the chest, usually within 30-60 minutes of eating. It can be worse at night because lying down makes it easier for the stomach acid to flow up into the oesophagus. The pain can sometimes be confused with angina because they appear in a similar location. The patient may also experience respiratory symptoms including shortness of breath, wheezing, cough and hoarseness. There is some link between GORD and asthma.Treatment involves removing aggravating factors, treating the symptoms and repairing damage. This involves:Modification of lifestyle factors including weight loss and dietary changesAvoid lying down within 2 hours of eatingMedications to neutralise or reduce production of stomach acidSurgery to repair damaged sphincter and remove stricture13.2PEPTIC ULCERSAn ulcer is a lesion that, due to constant irritation or impaired healing process, does not heal. Peptic ulcers are ulcers that occur in the upper digestive tract – either the stomach or duodenum.While there is certainly a link between stress and peptic ulcers, it is not as strong as was once thought. There are two main causes of peptic ulcers:Helicobacter pylori – a bacteria that is able to withstand the acid environment of the acid and attacks the mucosal liningNSAIDS and aspirin – non-steroidal anti-inflammatory medications and aspirin both cause irritation to the stomach lining and slow the production of the protective mucous.Excessive stomach acid – this could be over-production (often after stress is relieved) or lack of foodThe main symptom of peptic ulcers is a burning pain in the chest or abdomen which is often alleviated by consuming food or antacid medications. Other signs and symptoms can include nausea, vomiting, loss of appetite and anaemia from bleeding.If left untreated, a number of complications can occur:Haemorrhage – due to erosion of major blood vessels, can lead to shock and deathPerforation – the ulcer erodes right through the wall of the stomach or duodenum allowing food and bacteria into the peritoneal cavity which can lead to severe infectionScar tissue – can impede the absorption of nutrients and also restrict passage of food through the digestive tractCancer – increased risk of stomach cancerIf a person is diagnosed as having the H. pylori bacteria they can be treated with antibiotics. Ulcers from NSAIDs do not respond to antibiotics and the only way to stop them is to change medications.Antacids and medications that reduce production of stomach acid can both be used to alleviate symptoms.13.3GASTROENTERITISGastroenteritis is an inflammation of the gastrointestinal tract, usually the stomach or small intestine, from a number of different causes. The most common causes are viruses and bacteria but it can also develop from parasites, toxins or allergies. The main signs and symptoms of gastroenteritis are nausea, vomiting and diarrhoea. It can also cause cramps, bloating, gas and bleeding.Most gastroenteritis is self-limiting and clears up within a few days. Anti-diarrhoea medications are not recommended because they may slow the rate at which the pathogen is cleared from the system and therefore make the symptoms last longer. If the problem goes on for more than 2-3 days then doctors may look for some underlying condition like Crohn’s disease.The main treatment is rest and rehydration. If necessary, intravenous fluids may be needed to prevent dehydration. It is easier to prevent gastroenteritis than treat it. Key to prevention is good hygiene – careful food handling and washing hands especially after visiting the toilet. 13.4IRRITABLE BOWEL SYNDROMEIrritable bowel syndrome (IBS) is a condition of digestive dysfunction that cannot be explained by structural or physiological abnormalities of the digestive tract.It is characterised by persistent or recurrent bouts of diarrhoea, constipation or both and is often accompanied by flatulence, bloating, nausea or abdominal pain. Pain is often in the lower abdomen, with intermittent cramping, and alleviated by defecation. In order to be classed as IBS the condition needs to occur for at least 12 weeks over a 12 month period, without other explanation for the symptoms. Conditions such as coeliac disease or lactose intolerance need to be eliminated.While there does not appear to be a physiological cause, the condition is often exacerbated by stress or eating certain foods. Some women find the condition worsens during the premenstrual period.Because there is often no underlying cause, treatment involves managing stress and avoiding dietary triggers. Medications such as anti-spasmodics, anti-inflammatories, anti-depressants and antacids can help with symptoms.13.5INFLAMMATORY BOWEL DISEASEInflammatory bowel disease (IBD) should not be confused with IBS. It is a term used to describe two related conditions – Crohn’s disease and ulcerative colitis.Both conditions are characterised by severe inflammation of the bowel without an identifiable cause. There appears to be a genetic link with both conditions running in families. Both conditions primarily affect the digestive system but they can also affect other parts of the body – including joint arthritis, mouth ulcers and skin rashes.13.5.1CROHN’S DISEASECrohn’s disease often starts in the ileum (the terminal section of the small intestine) but can spread throughout the small and large intestines as far as the rectum. It is often not continuous and appears as irregular patches along the intestines. Over time the inflammation leads to ulceration which can penetrate through the wall of the intestine. They can also create scar tissue which can partially block the intestine. Crohn’s disease often goes through acute phases with periods of remission. Signs and symptoms during an acute phase include:Abdominal pain, especially lower right quadrantCrampingDiarrhoea (often bloody)Weight lossFeverJoint painMouth ulcersIntestinal scarring can lead to malabsorption syndromes. This is especially problematic in children as it can lead to stunted growth and developmental delays.Crohn’s disease has also been linked to inflammation of the liver and bile duct which can result in jaundice.Treatment usually involves anti-inflammatories, including steroids, and immunosuppressant medications to control the inflammation.Sections of damaged intestine can be removed surgically but the problem tends to flare up elsewhere.13.5.2ULCERATIVE COLITISUlcerative colitis is restricted to the large intestine. It usually begins in the rectum and spreads progressively along the large intestine. While there is no established cause, it is generally considered to be an autoimmune condition with the immune system attacking the mucous membranes of the rectum and intestine. This causes inflammation which leads to painful ulceration.Like Crohn’s disease, ulcerative colitis goes through acute periods followed by remission. The signs and symptoms of an acute episode are:Abdominal pain and crampingPainful, chronic diarrhoeaBlood in stoolsLoss of appetiteFeverThe condition can lead to anaemia due to blood loss. It can also cause inflammation of the liver leading to jaundice.Treatment involves steroid and immunosuppressant medications. Nicotine has been found to be effective in many cases so nicotine patches may be prescribed. Many patients will eventually require surgery. Where possible, the bowel can be re-sectioned making it shorter. When too much of the bowel is removed the patient will require a colostomy bag.13.6APPENDICITISThe appendix is a small tube attached to the cecum of the large intestine which contains lymphoid tissue. It has a small role to play in fighting bacteria in the large intestine but is not vital to our survival. Appendicitis occurs when the appendix gets infected or obstructed leading to inflammation. It usually happens between the ages of 5 and 30 but can occur at any age. The first symptom is often general abdominal pain which eventually settles in the right lower quadrant. It is often accompanied by fever, nausea, vomiting, loss of appetite, diarrhoea or constipation. The pain can be exacerbated by coughing, sneezing or abdominal movement. Complications of appendicitis are gangrene or rupture, both of which have severe consequences. Once infection has been identified, the appendix is removed by surgery. Some patients will receive antibiotics first, especially if there are abscesses in the appendix, to reduce the risk of infection being released into the body during surgery.13.7BOWEL CANCER401129510668000Bowel cancer is the second most common cancer in Australia and is most common in people over 50 years old. It occurs in the colon (large intestine) and rectum and is also known as colorectal cancer. Most cases of bowel cancer begin as benign polyps. A polyp is a small mass of tissue that protrudes from the membrane of the colon. Large polyps or ones that have been there for a long time are more likely to become cancerous.There are a number of risk factors that increase the likelihood of developing bowel cancer:Age – over 50 years oldHigh dietary fat and sugar intakeLow dietary fibreLow dietary intake of vitamins A, C and EFamily history of cancer or polypsCrohn’s disease or ulcerative colitisIf identified early, polyps can be removed with a recovery rate over 90%. However, if left untreated, the cancer can spread through the wall of the bowel. Over time it can spread to the lymph nodes and can also metastasise to other organs including the brain, liver and lungs.Bowel cancer often goes undetected for a long time as there are no noticeable signs or symptoms in the early stages. The first sign is often unexplained anaemia or blood in the stools, by which time the cancer has already developed. Signs and symptoms which can indicate the presence of bowel cancer include:AnaemiaBlood in stoolsConstipationAbdominal painFeeling of incomplete bowel movementsWeight lossBowel screening tests are available from either a GP or a pharmacy which test for blood in stools. A positive test is an indication that cancerous polyps may be present but it is not foolproof. Not all cancerous polyps bleed. There are also other reasons why blood may appear in the stools including ulcers or haemorrhoids. People in high risk groups are recommended to get a colonoscopy as this is a more reliable method of detection.Bowel cancer is divided into 4 stages:Stage I – has not yet penetrated the deep layers of the bowel wallStage II – has penetrated through to the muscle layer of the bowel wall but has not spread to the lymph nodes or metastasisedStage III – has spread to the lymph nodes but no metastasisStage IV – has metastasised to other organs in the bodyStages I and II are usually treated with surgery alone but stages III and IV require chemotherapy and possibly radiation therapy as well as surgery. Depending on how much of the bowel has to be removed, the person may require a colostomy bag after surgery.Cancer that is treated in stage I or II has about a 90% survival rate but stage IV has just a 10% survival rate so screening and early detection is important.41814753194050013.8LIVER CIRRHOSISCirrhosis is a condition where much of the functioning tissue of the liver has been replaced with fibrous tissue. The liver is normally very good at regenerating. It is the only organ that has the capacity to grow back if part of it is removed. However, long term chronic irritation or infection can be too much for even the liver to handle. When this happens, normal healthy cells stop regenerating and are gradually replaced by fibrous scar tissue. This scar tissue is interspersed with small pockets of functioning cells which give the liver a bumpy appearance.During the early stages of cirrhosis the liver can become enlarged due to the proliferation of fibrous tissue. As the fibrous tissue contracts the liver then shrinks.Cirrhosis often goes unnoticed until the condition reaches an advanced state. Early indications can include nausea, weight loss, red patches on skin, weakness and diarrhoea. These are all common symptoms of many other diseases.499046516446500As cirrhosis becomes advanced, a number of complications can develop including:Portal hypertension – the portal vein from the digestive system to the liver becomes congested blocking the flow of blood and nutrientsEnlarged spleen – it cannot drain fluid into the portal vein so it swells and may rupture5229225626110Ascites00AscitesAscites – portal hypertension causes fluid from blood and lymph vessels to leak into peritoneal cavity causing oedema and abdominal distension called ascitesInternal varicose veins – especially in stomach and oesophagus due to hypertension which can ruptureAbnormal bleeding and bruising – liver is no longer able to produce clotting factorsJaundice – yellow colour of skin and membranes. The liver is no longer able to break down the bilirubin pigmentSystemic oedema – the liver no longer produces the protein albumin which is needed to maintain fluid balance, leading to oedema throughout the bodyHormone disruption – the liver cannot break down oestrogen leading to feminisation in men and loss of menstruation in womenEncephalopathy – the liver cannot break down toxins which enter the central nervous system causing inflammationKidney failure – due to reduced blood flow from the liver to the kidneysSo what causes cirrhosis? Excessive alcohol consumption is the most common cause, but there are other causes including hepatitis, obstruction of the bile duct, poor nutrition and environmental toxins. There is limited treatment for cirrhosis – by this stage, the damage to the liver has become irreversible. The aim is to slow the rate of deterioration by eliminating alcohol consumption, preventing infection and managing levels of carbohydrate and protein in the diet. Survival rates from liver transplants have greatly increased, especially if the person alters their lifestyle. However a suitable organ donor is not always available.13.9HEPATITISHepatitis simply means inflamed liver. It can be caused by toxins or drug reactions, but most of the time it is caused by a viral infection.While there are many different types of viral hepatitis, there are 3 strains that account for over 90% of infections – hepatitis A, B and C. Hepatitis AHepatitis A is a benign, short-lived disease which rarely results in lasting damage. It is spread by the oral-faecal route which is one of the main reasons why hand-washing is so important. Signs and symptoms are more acute than for other forms of hepatitis but they are more short-lived. They include weakness, nausea, fever, loss of appetite, possible jaundice, dark urine and pale stools.Treatment consists simply of rest and fluids. There is a vaccine available for people travelling to places where there is a high prevalence of the disease.Hepatitis BThe symptoms of hepatitis B are less severe than hepatitis A but the disease goes on for a much longer period and there is a greater risk of permanent damage.Hepatitis B has an incubation period of 1-6 months followed by 3-6 months of symptoms. About 5% of people will go on to develop a chronic infection. Chronic hepatitis is one of the leading causes of cirrhosis of the liver.Hepatitis B is transmitted through blood and bodily fluids. The same precautions need to be taken as for HIV – avoid unprotected sex, sharing needles and other methods of blood-to-blood transmission. The virus can survive for up to 7 days outside the human body so sterilisation of medical or tattooing equipment is important. Anti-viral medications are available for hepatitis B but they only have limited effectiveness. A vaccine is available and is part of the National Immunisation Schedule for all Australian children.Hepatitis CHepatitis C is the most dangerous of the common strains with around 75-85% of patients going on to develop long term chronic infection, greatly increasing their risk of cirrhosis and cancer.Hepatitis C is transmitted by blood-to-blood contact so the most common method of transmission is through shared needles by drug users although contaminated medical, tattooing or piercing equipment can also cause infection.The signs and symptoms are generally weakness, fever, nausea and mild jaundice. They are less severe than the other strains and some people may not even realise that they have been infected. There is no vaccination for hepatitis C and anti-viral medications have limited success to prevention is important.43313352514600013.10JAUNDICEJaundice is a condition where the skin acquires a yellow colour due to a build-up of excess of the pigment bilirubin. Bilirubin is a normal by-product of the breakdown of red blood cells. The liver then processes the bilirubin into bile which is used in the digestive system for the digestion and absorption of fats and fat-soluble vitamins.Jaundice occurs when the liver fails to process the bilirubin at the rate at which it is being produced. There are three main types of jaundice:Haemolytic jaundice – there is an abnormally high turnover of red blood cells. Although the liver is functioning normally it cannot keep up with the level of bilirubin that is produced.Hepatic jaundice – the liver becomes dysfunctional due to infection (e.g. hepatitis, malaria), congenital defect, inflammation or scarring (cirrhosis) which decreases the rate at which the liver is able to process bilirubinObstructive jaundice – obstruction of the bile duct means that the liver is not able to clear bileJaundice should always be taken seriously as it can be an indication of serious liver disease.Treatment of jaundice consists of identifying and treating the underlying condition.3896995336550013.11GALLSTONESGallstones are crystallised deposits of substances that collect within the gallbladder. The gallbladder is an organ that stores and concentrates bile from the liver. It then delivers the bile to the small intestine via the common bile duct when it is required.About 80% of gallstones are derived from cholesterol while the other 20% are made from calcium tinted with bilirubin.There are a number of factors that increase the risk of developing gallstones includingObesity – reduces the amount of salts and increases the level of cholesterol in bileOestrogen – increases cholesterol in bile and reduces gallbladder activity, allowing the cholesterol to crystalliseGender – women are more likely to develop gallstones than men due to higher oestrogenAge – most patients are over 60 years oldCholesterol-lowering drugs – cause a build-up of cholesterol in the gallbladder as part of the process of eliminating it from the bodyDiabetes – high levels of triglyceridesRapid weight loss – encourages metabolism of fat for energy, increasing cholesterol levelsFasting – reduces gallbladder activity, causing stagnation of bileMany people with gallstones are asymptomatic however, if a gallstone gets lodged in the bile duct, it can cause very severe pain, sometimes accompanied by nausea or fever. If the bile duct becomes blocked it can lead to complications. Obstruction of the bile duct can cause jaundice as the liver is unable to clear the bile. It is also the leading cause of pancreatitis (inflammation of the pancreas) as the pancreas is unable to clear the pancreatic acid. The gallbladder can be surgically removed. This will mean that no future gallstones will be produced. We are able to survive without a gallbladder but we are no longer able to store the bile until needed. Instead there is a constantly low-level flow into the small intestine. The main complication of this is a reduced ability to absorb fat-soluble vitamins.LESSON 14 – URINARY DISORDERS14.1Urinary Tract Infections 14.2Pyelonephritis14.3Kidney Stones14.4Renal Failure14.4.1Acute Renal Failure14.4.2Chronic Renal Failure14.1URINARY TRACT INFECTIONSA urinary tract infection (UTI) refers to infections of any part of the urinary system including:Cystitis – infection of the bladderUrethritis – infection of the urethraNephritis – infection of the kidneysThe term is commonly used to refer to lower UTIs – urethritis and cystitis. In this section, we will concentrate on these conditions. We will look at kidney infections separately.The urinary tract is normally a sterile environment. Urine contains waste products to be eliminated but it should not contain living organisms like bacteria or viruses. The slightly acidic quality of the urine helps to kill bacteria while the mucous produced by the membrane of the urinary tract also helps to protect against pathogens. Occasionally, pathogens do manage to enter the body via the urethra. UTIs are much more common in women than men because the urethra is much shorter. The position of the female urethra also means that there is much higher chance of cross contamination from faecal matter.Most lower UTIs are caused by E. coli. Other causes include other bacteria like streptococcus and other types of microorganisms including chlamydia. Obstruction of urine flow can increase the risk of UTIs. Normally, voiding urine helps to wash out any microorganisms that enter the urethra but if it becomes obstructed the microorganisms will multiply and may pass up to the kidneys.Risk factors that increase the likelihood of UTI include:GenderSexual activityProstate enlargementPost-menopausal womenAgePoorly controlled diabetesCatheterisationSigns and symptoms of UTI are painful, burning urination, urgency to urinate and bloody or cloudy urine.Most UTIs can be treated with antibiotics but the cause of the UTI should be established first before prescribing them.14.2PYELONEPHRITISPyelonephritis is an inflammation of the kidneys. It can be divided into two types – acute or chronic. Acute pyelonephritis is caused by a bacterial infection, usually E. coli. Most kidney infections come from bacteria which have entered the urinary tract via the urethra. The exception is staph. aureus which enters from the blood stream. Kidney infections occur most often in chronically ill people and those receiving immunosuppressant treatment. Manifestations of acute pyelonephritis are fever and lower back pain. The patient may also experience UTI symptoms of painful and frequent urination. They may also experience nausea.Acute pyelonephritis can be treated with antibiotic drugs. Chronic pyelonephritis is associated with reflux – where urine flows backwards from the bladder to the kidneys. It is also associated with hypertension, drug use, especially NSAIDs, and other toxins which are cleared from the body via the kidneys. Chronic pyelonephritis leads to the formation of scar tissue and can eventually lead to renal failure.In both types it is important that the patient maintain adequate hydration.14.3KIDNEY STONESKidney stones are also known as renal calculi. They are small crystallised structures made from solutes within the urine. Stones are formed when the urine becomes over-saturated with certain substances. The main substances found in kidney stones are:Calcium oxalate and calcium phosphate (80-90% of kidney stones)Magnesium ammonium phosphateUric acidCalcium StonesThese are the most common type of kidney stones, accounting for about 80-90% of all kidney stones. 401955036131500They are usually associated with high levels of calcium in the blood or urine. Reasons include:Bone resorption due to immobilityCertain medications cause bone resorptionVitamin D intoxicationHyperparathyroidismBone diseaseOther factorsExcessive oxalates in dietMagnesium Ammonium Phosphate StonesThese are formed in alkaline urine in the presence of certain bacteria. These stones enlarge as the bacteria levels increase. They are almost always associated with alkaline urine and UTIs. It is difficult to treat the bacteria within the stone with antibiotics. The stones often grow too large to pass through the ureter and must be removed surgically. Uric Acid StonesUric acid stones form in conditions of gout and high concentrations of uric acid in the urine. They are associated with a high purine diet. ManifestationsThe key manifestation of kidney stones is pain. There are two types of pain associated with kidney stones:Renal colic – acute, intermittent, agonising pain in upper abdomen that can radiate to lower abdomen or groin. Clammy skin, nausea and vomiting are common.Non-colicky pain – dull, aching pain in lower back or side that varies from mild to severe. Often exacerbated by drinking large quantities of fluid.TreatmentTreatment usually involves pain management until the stones are passed and treatment of the underlying condition to prevent recurrence. In some cases surgery may be necessary to remove the stones. More recently, ultrasound has been introduced as a method of breaking down the stones without the need for surgical intervention.14.4RENAL FAILURERenal failure means that the kidneys are no longer able to adequately remove metabolic products and toxins from the blood and regulate the fluid, electrolyte and acid balance of the body fluids. Renal failure can be either acute or chronic in nature depending on the cause.14.4.1ACUTE RENAL FAILUREAcute renal failure is a rapid, sudden decline in kidney function to less than 50% of normal levels over hours or days. There are 3 main reasons why this may occur:Pre-renal problems – problems which prevent blood flowing to the kidneys. Includes reduced blood volume, low blood pressure, extreme dehydration or an embolism blocking the renal artery.Intra-renal problems – problems within the kidneys. Includes nephritis (inflammation of kidneys), embolism within the kidney, bacterial infection or drug reactions.Post-renal problems – problems which prevent fluid leaving the kidneys. Includes kidney stones, enlarged prostate or other conditions which block the flow of urine.Manifestations of acute renal failure include:Sharp decrease in urine outputAbnormally high levels of urea, uric acid and creatinine in bloodPresence of protein, haemoglobin or myoglobin in urineRed or brown coloured urineOedemaAcute renal failure is a potentially life-threatening condition but can often be reversed if it is identified and the cause of the condition is addressed. Fluids, electrolytes need to be carefully monitored in order to maintain homeostasis. Adequate calorie intake is essential to prevent breakdown of body proteins which will produce more nitrogenous wastes. Dialysis may be required to keep water, electrolytes and nitrogenous wastes within normal levels until the kidneys recover sufficiently.14.4.2CHRONIC RENAL FAILUREChronic renal failure is due to long term kidney damage and can take years to develop.Chronic kidney disease is usually categorised into stages, depending on the amount of function that has been lost, with renal failure being the final stage. Risk factors for developing chronic kidney disease include:DiabetesHypertensionFamily history of kidney diseaseNephritisSystemic lupus erythematousPolycystic kidney diseaseThe signs and symptoms of chronic kidney disease develop slowly and are often not recognised until the disease is in an advanced state. They included:Accumulation of nitrogenous wastes in bloodFluid, electrolyte and acid homeostasis imbalancesChanges in bone densityAnaemiaBleeding disordersHypertensionCongestive heart failureGastrointestinal upsetPeripheral neuropathyEncephalopathyDry skinInability to eliminate drugs and toxinsTreatment is focussed on slowing the progress of the disease. This includes reducing pressure on the kidneys by managing hypertension and diabetes and stopping smoking.In advanced cases dialysis may be needed to replace the lost kidney function. Organ transplant is indicated in many cases but is not always appropriate and a suitable donor must be found.LESSON 15 – REPRODUCTIVE DISORDERS15.1Polycystic Ovarian Syndrome15.2Fibroids15.3Endometriosis15.4Premenstrual Syndrome15.5Menopause15.6Infertility15.6.1Female Infertility15.6.2Male Infertility15.6.3Infertility Treatment15.7Cancer15.7.1Breast Cancer15.7.2Ovarian Cancer15.7.3Cervical Cancer15.7.4Prostate Cancer15.1POLYCYSTIC OVARIAN SYNDROME34099509144000During the ovulation cycle, a follicle in the ovary enlarges and becomes filled with fluid to support the developing egg prior to ovulation. Sometimes the follicles do not develop fully and ovulation does not occur. When this happens the fluid is not reabsorbed which produces a follicular cyst. Most cysts disappear spontaneously within 60 days and do not cause any problems.In polycystic ovarian syndrome (PCOS) multiple cysts develop and do not spontaneously resolve. As a result, the ovaries become enlarged. Presence of the cysts also interferes with normal ovulation. PCOS is a common condition affecting 5-10% of women however the cause of it is unknown.Apart from anovulation (failure to ovulate), the manifestations of the condition are:Menstrual irregularitiesRaised luteinising hormoneRaised testosteroneInfertilityAcneHirsutismTendency for obesityInsulin resistanceHypothyroidismWhile obesity and insulin resistance are common manifestations of the disease, recent thought is that they are also risk factors for developing it. The preferred method of treatment is lifestyle modification. Evidence has shown that reducing obesity and increasing physical activity not only reduces insulin resistance but also increases ovulation and fertility. Insulin-sensitising drugs such as metformin can also help but attention to diet and exercise is preferable.Oral contraceptives can be used for treating menstrual irregularities, hirsutism and acne. Women with fertility issues who wish to conceive can take fertility drugs but these need to be monitored closely.15.2FIBROIDSFibroids or leiomyomas are benign neoplasms of smooth muscle tissue found in the uterus. They are thought to affect approximately 20-25% of women of child-bearing age although it is difficult to be sure because many are asymptomatic and therefore go undetected. It is not known why they occur.Fibroids are usually detected during a routine pelvic examination or during investigations of abnormal bleeding. Signs and symptoms of fibroids can include:Menorrhagia (excessive bleeding)Dysmenorrhoea (painful menstruation)Frequent urination (due to pressure on bladder if large enough)ConstipationAbdominal distensionMost fibroids grow slowly and are not considered serious however there are some potential complications. Blockage of fallopian tubes leads to infertilityLarge fibroids can lead to lack of space in uterus for a foetus during pregnancyCan cause excessive menstrual bleeding leading to anaemiaCan place pressure on the bladderOestrogen and progesterone can increase the size of a fibroid and they tend to resolve after menopause.Many fibroids do not require treatment however it is important to ensure that they are benign. If the fibroids grow too large or cause complications like excessive bleeding they can be removed surgically. 15.3ENDOMETRIOSISEndometriosis is a condition where abnormal growths of endometrial tissue occur outside the uterus. The cause of endometriosis is unknown. One theory is that fragments of endometrium pass up the fallopian tubes during menstruation and escape into the peritoneal cavity. Another is that the endometrial cells metastasise through the lymphatic and blood circulations. The endometrial tissue can grow and bleed under the influence of hormones just like in the uterus, but the menstruation cannot escape through the uterus and remains in place. This causes inflammation which leads to the development of fibrous tissue around the endometrial tissue.Many women with endometriosis experience very painful periods and abdominal bloating. They may also experience some rectal bleeding depending on the location of the endometriosis. There is also a higher than normal rate of infertility in women with endometriosis.Fibrous tissue surrounding the endometriosis can lead to adhesions within the abdominal cavity. The effects of the adhesions depend on where they occur. Ovarian adhesions can lead to infertility. Treatment depends on the severity of the condition and the fertility status of the patient. In mild cases and where there is no immediate desire for fertility analgesic medication to manage painful periods will be adequate.Hormone treatments including contraceptive pills can also be used to control symptoms. In women who have severe symptoms or where adhesions have developed, surgery can be sued to remove the endometrial tissue. Whether or not this is possible depends on the location. The best fertility treatment for women with endometriosis is in vitro fertilisation (IVF).15.4PREMENSTRUAL SYNDROMEPremenstrual syndrome (PMS) is the name given to a collection of symptoms experienced by women during the luteal phase of the menstrual cycle – the time between ovulation and menstruation. PMS affects up to 85% of women of menstruating age however the severity of the symptoms varies greatly. About 5-10% will experience symptoms so severe that it affects their ability to carry out daily activities. This is known as premenstrual dysphoric disorder (PMDD).Factors which are known to trigger PMS include:Hormonal imbalances – changes in oestrogen and progesterone levels have been linked to many of the symptomsNutritional deficiencies – including vitamin B6, calcium and some essential fatty acidsSerotonin imbalance – levels of serotonin, which produces feelings of well-being, are decreased during the luteal periodOther factors – stress, general health and other factors can influence PMSThere are many different symptoms which can be included in PMS. Not everyone will have the same symptoms. Common ones include:DepressionMood swingsAnxiety or irritabilityFatigue or lethargyChanged sleep patternsDifficulty concentratingDiminished interest in activitiesHeadacheBreast tendernessBloating and fluid retentionAbdominal painGastrointestinal upsetIncreased appetiteIn order to reach a diagnosis of PMS, the symptoms should be limited to the luteal phase and be present for 2 or more consecutive cycles. Other diagnoses such as depression also need to be excluded. PMS is often treated with contraceptive pills however this is not always helpful. In fact the increased levels of oestrogen and progesterone can exaggerate symptoms in many cases. Anti-depressants may be prescribed to address serotonin imbalances.Getting adequate sleep, maintaining a healthy diet and regular exercise can all help to manage symptoms. 15.5MENOPAUSEMenopause is the cessation of the menstrual cycle. The average age at which this happens is around 50 years old.Menopause does not happen overnight. Menstrual function generally declines over a few years before stopping altogether. This period is called perimenopause and is when many women experience the symptoms that are commonly associated with menopause.So what happens? After puberty, the ovaries release an egg every month in the process called ovulation so that it can be fertilised. During this process, the ovaries manufacture hormones including oestrogen and progesterone which are responsible for creating feminine characteristics and for regulating the monthly cycle. As a woman ages, the number of eggs gets less and the ovaries begin to lose their function. They make less oestrogen and progesterone and they release their eggs less and less frequently until they stop altogether.In the year 1900 the average life expectancy for women was around 50 years old so menopause was not a common issue, but now many women live past 80 and it has become a common condition.While age is the main cause of menopause, it can also happen due to surgical removal of the ovaries or radiation therapy for ovarian cancer. When the ovaries stop making oestrogen and progesterone, other tissues in the body still make small amounts but the overall level in the body is much lower than before leading to a number of mon symptoms of perimenopause and menopause are:Loss of menstrual periodsHot flushesNight sweatsMood swingsDecreased sex driveVaginal itchiness or drynessPoor concentration and memoryPost-menopausal women also have an increased risk of cardiovascular disease and osteoporosis. It has been shown that the increased risk is not due to age alone, but is linked to changing hormone levels.The main treatment for peri-menopausal symptoms is hormone replacement therapy which involves giving oestrogen supplements but this increases the risk of breast cancer and ovarian cancer. It also increases the risk of hypertension, blood clots and gallbladder disease.There are alternative medications for the treatment of hot flushes but they are less effective than oestrogen.Because of the increased risk of osteoporosis, calcium supplements are recommended for post-menopausal women.15.6INFERTILITYInfertility is the inability to conceive a child after at least 1 year of trying. This is slightly different to sterility which is the inability to reproduce due to congenital abnormality or surgery. The key difference is that sterility is a permanent condition.Approximately 15% of couples have fertility issues, while about 1% are sterile. Reasons for infertility are evenly split between male and female. In a number of cases, there is no apparent cause attributable to either partner.15.6.1FEMALE INFERTILITYThere are a number of factors which can affect female infertility including:Ovulatory dysfunction – this can be a lack of ovulation or irregular ovulation, making it difficult to time the fertile periodLuteal phase defect – a discrepancy between the start of the luteal phase of the menstrual cycle and the ovulation date, meaning that the egg cannot implant successfullyCervical mucus problems – poor quality mucous means the sperm cannot travel into the uterus. This can be due to low oestrogen, cervical abnormalities or sexual diseaseUterus abnormalities – can prevent successful implantation. These include fibroids, polyps, congenital abnormalities or scar tissue. Scar tissue from previous caesarean sections can affect future fertilityTubal abnormalities – abnormalities with the fallopian tubes prevent the passage of the egg to the uterus. This can include congenital abnormalities, ectopic pregnancy, fibroids, endometriosis or tubal ligation (surgical tying of the tubes)15.6.2MALE INFERTILITYMale infertility is more straightforward. Men must produce sperm in sufficient quantity, and with sufficient motility to travel through the female reproductive tract. Factors which affect male fertility include:Hormonal imbalancesCongenital anatomical abnormalities (e.g. lack of vas deferens)Abnormal sperm production – due to disease e.g. mumps, chemical or radiation exposureAbnormal motility – inability of sperm to moveSexual dysfunction – impotence or premature ejaculation15.6.3INFERTILITY TREATMENTThe goals of infertility treatment are to identify and address the cause of the infertility. While this often focuses mainly on the female, male factors also need to be considered. A series of tests can often be carried out to determine the cause. The range of tests will often depend on cost.Sometimes the cause may be something as simple as an irregular menstrual cycle, in which case a simple test can detect the fertile period.Medical treatments such as hormone therapy can be used for a number of causes of both male and female infertility. Where female infertility is treated with hormone therapy, there is a risk of multiple eggs being produced and fertilised. When this happens, the couple needs to consider carefully the additional risks of carrying multiple babies to term. The more babies, the greater the risk due to limited space in the uterus and limited availability of nutrients.In vitro fertilisation (IVF) is an option for couples who are unsuccessful at conceiving naturally. Eggs are surgically removed from the ovaries and sperm removed from the testes. The sperm are washed to improve motility before being introduced to the eggs. After 48-72 hours a fertilised egg is selected and placed into the uterus where it will implant into the endometrium. This needs to be done at the correct stage of the menstrual cycle. The woman may receive hormone therapy to strengthen the endometrium prior to implantation.The psychological effects of infertility should not be underestimated. Sometimes stress and anxiety may be the cause of the infertility. Failure to conceive and the processes that are the couple have to undergo in their quest to have a child can be traumatic and feelings of grief and depression are common. Psychological counselling has an important place in fertility treatment. 15.7CANCERReproductive cancers are some of the most common cancers for both men and women. They often go undiagnosed in early stages due to a reluctance to seek medical attention. This can be due to embarrassment or fear that the testing procedure will be painful.15.7.1BREAST CANCERBreast cancer gets a lot of publicity, mainly because of its increase during recent decades. It is the most common cancer in women accounting for almost 30%. Breast cancer mainly affects women over the age of 40 but it can occur at any age and occasionally occurs in men.The most common type of breast cancer is a ductal carcinoma – that is a cancer of the ducts which deliver the milk to the nipple. They account for around 80% of all breast cancers. Most of the remaining cancers are lobular carcinomas – cancer of the lobes where the milk is produced. About 5-10% of breast cancers are caused by genetic factors. There are two genes that have been identified, known as BCRA1 and BCRA2, both of which are found on chromosome 13. 318706510350500Risk factors for developing breast cancer include:BCRA1 and BCRA2 genesFamily historyAgeEarly onset of pubertyLate first pregnancy or no pregnancyObesity Alcohol intakeHormone replacement therapy or contraceptivesEarly detection improves survival rate. Early signs can be hard to detect. They are usually found first by self-examination and then confirmed by mammogram and biopsy. The signs include:Lump in breast“orange peel” texture to skinAsymmetrical breast growthInverted nippleRed or bleeding nippleWomen over the age of 40, particularly those with a family history, should get regular breast examinations.Breast cancer is an aggressive disease which can metastasise first to the axillary lymph nodes and then to other parts of the body. The progress of breast cancer is divided into stages:Stage I – the tumour is less than 2cm and confined to the breastStage II – the tumour spreads to the axillary lymph nodesStage III – the cancer spreads to tissues surrounding the breast or to other lymph nodesStage IV – the cancer spreads to other organs of the bodyTreatment depends on the stage of development of the cancer. Lumpectomy – removal of a section of the breast leaving unaffected breast tissue intact.Mastectomy – removal of the whole breast and nearby lymph nodes if requiredRadiation – stop or slow growth and shrink tumour to make it easier to remove surgicallyChemotherapy – drug therapy to destroy tumour cells.Hormone therapy – medication which blocks oestrogen from tumour cells to stop them growing. Usually tamoxifen – side effects include osteoporosis as it affects calcium uptake by the bonesBreast cancer is not generally a preventable disease, but some women who have the BCRA1 or BCRA2 gene are electing to have mastectomies to remove all breast tissue as they do not wish to take the risk of developing the disease.15.7.2OVARIAN CANCER42767258826500Ovarian cancer is a malignant tumour in one or both of the ovaries. It is less common than breast cancer but it has a high mortality rate because it has few symptoms in the early stages it often goes undetected for a long time. Ovarian cancer can occur at any age but usually affects women over the age of 60.About 90% of ovarian cancers are epithelial cancers or adenocarcinomas. While most tumours are non-functional, some can secrete hormones. Some secrete large quantities of oestrogens while others secrete androgens which inhibit ovulation and oestrogen production.Risk factors for developing ovarian cancer include:Genetics – several genes have been identified which increase the riskFamily historyReproductive history – there is increased risk in women who have not had children or who have had multiple miscarriagesHistory of other cancers – particularly breast or colon cancerOestrogen therapy – hormone replacement therapy or contraceptive pillHigh fat dietEarly signs and symptoms of ovarian cancer are often very subtle and mimic many other conditions so they are often overlooked. They include:BloatingNauseaDiarrhoeaConstipationVaginal bleedingChange in menstrual cycleChange in weightAs the condition advances the patient may develop a palpable mass in the abdomen, increased abdominal girth and ascites (fluid in the peritoneal cavity). For functional tumours, additional symptoms are associated with the hormones produced. There are four stages of development of ovarian cancer:Stage I – the cancer has not spread beyond the ovariesStage II – other pelvic organs such as the bladder or uterus are affectedStage III – tumours are found in the peritoneum and pelvic lymph nodesStage IV – cancer has metastasised to distant organs, usually the lungs or liverThe main form of treatment is surgery to remove the ovaries and possibly the uterus as well. The patient may also receive chemotherapy. Radiation therapy is not usually used for this kind of cancer. Survival rate depends on the stage of development when the cancer is detected. 15.7.3CERVICAL CANCERCervical cancer is a growth of malignant cells in the membrane that lines the cervix. It is easily detectable and also easily treated if detected early.39528751270000Cervical cancer is most commonly caused by the human papilloma virus (HPV) which is spread by sexual contact. Vaccination against HPV is now included in the National Immunisation Schedule for girls aged 10-15 to immunise them before they become sexually active. Although cervical cancer is usually caused by HPV, it can sometimes be found in women who have not been exposed to the virus. Smoking greatly increases the risk of developing cervical cancer so it is important to stop smoking. Other risk factors include immunodeficiency and long term oral contraceptive use. There are few noticeable signs and symptoms in the early stages. Women may notice bleeding outside of the menstrual cycle, especially during intercourse. In more advanced stages they may notice pelvic or lower back pain, including pain on intercourse.Cervical cancer is detected by a Pap smear (named after its inventor, Dr Papanicolaou). It involves taking a scraping of cells from the cervix and then examining them under a microscope for any abnormalities. Ideally the first smear should be taken 3 years after first sexual intercourse or at age 21, whichever comes sooner. The current recommended frequency (as at January 2015) is every two years. Cervical cancer is not always caused by HPV so it is important to have Pap smears even if a woman has been vaccinated or has never had sexual intercourse. The Pap smear picks up changes in the epithelial cells of the cervix known as cervical intraepithelial neoplasm (CIN). The development of these changes is divided into stages:CIN 1 – changes to less than 1/3 of the thickness of the epitheliumCIN 2 – changes to 2/3 of the thickness of the epitheliumCIN 3 – changes to more than 2/3 of the epithelium, up to full thicknessCarcinoma – cancer, involves full thickness and may spread to other tissues or organsCIN 1 can spontaneously resolve in some cases, but can also progress to CIN 2 or CIN 3 so it should not be ignored. CIN 2 and CIN 3 are likely to progress to cancer if left untreated. Once CIN or cancer has been identified by Pap smear, the doctor will carry out a colposcopy (visual examination) and biopsy to confirm the diagnosis and determine the stage of development. The main treatment for cervical cancer is surgery. This may involve removal of the cervix, full hysterectomy or removal of other tissues depending on where the cancer has spread. Chemotherapy and radiation therapy are also used especially where the cancer has spread.15.7.4PROSTATE CANCERThe prostate gland is part of the male reproductive system. It produces a large part of the fluid content of semen. The prostate gland sits just below the bladder and surrounds the urethra. Prostate cancer is the most common cancer in men apart from skin cancer.The prostate gland often becomes enlarged in older men without becoming cancerous. This is known as benign prostatic enlargement.Prostate cancer is generally a condition associated with age, with most cases being over the age of 50 and the average age of diagnosis being 65 years old. 33102552413000The exact cause of prostate cancer is unknown but it appears to be linked to testosterone as it is not found in men who have had the testicles removed or do not function. Other risk factors are increasing age, family history and high fat diet.There are two main methods of diagnosis. A digital rectal examination is a physical examination by the doctor who inserts a finger into the rectum to palpate the prostate and determine whether it is enlarged. Many men are afraid of this procedure but it is generally quick and painless.The other method of detection is by a blood test which looks for prostate-specific antigen(PSA). Levels of PSA in the blood go up and down and can also be influenced by other conditions including benign prostate enlargement, recent sexual activity and infection.While the above tests can give an indication, diagnosis can only be confirmed by a biopsy.Signs and symptoms of prostate cancer are:Enlarged, hardened prostateDifficulty in passing urinePainful urinationBlood in urinationImpotence If left untreated, prostate cancer can metastasise to nearby lymphatic tissue. It can also metastasise to the bones of the pelvis and lower spine. This can result in lower back pain.Treatment of prostate cancer usually involves surgery to remove the prostate and radiation therapy. Hormone therapy can be used to reduce the levels of testosterone which will slow the development of the disease. Chemotherapy is used in cases which have spread to other tissues of the body.LESSON 16 - ENDOCRINE DISORDERS16.1Diabetes Mellitus16.1.1Type I Diabetes16.1.2Type II Diabetes16.1.3Gestational Diabetes16.1.4Complications16.2Hyperthyroidism16.3Hypothyroidism16.4Cushing Syndrome16.5Adrenal Insufficiency16.1DIABETES MELLITUSDiabetes mellitus is not a single disease, but rather it is a collection of conditions which result in elevated blood sugar levels. All cells in the body need energy in order to function. The main source of energy is glucose. The pancreas produces a hormone called insulin. It produces the insulin in the beta cells of the Islets of Langerhans which are hormone-producing glands. Insulin acts on the cells of the body and triggers them to absorb glucose. When either no insulin is produced or the cells become resistant to glucose, the cells do not absorb the glucose and it remains in the bloodstream. The main types of diabetes are:Type I diabetes – an autoimmune condition resulting in destruction of the cells in the pancreas which create insulinType II diabetes – a lifestyle condition which results in the body cells being less receptive to insulin, and the pancreas becoming less efficientGestational diabetes – a short term condition during pregnancyNote: Diabetes insipidus is not related to diabetes mellitus. It is a condition in which the pituitary gland does not produce anti-diuretic hormone resulting in excessive urination. The conditions should not be confused. 16.1.1TYPE I DIABETESType I diabetes is and autoimmune condition in which the body’s own immune system attacks and destroys the beta cells of the pancreas which are responsible for producing insulin. The reason for this occurring is largely unknown but it is thought that it may be triggered by a viral infection. It most commonly occurs in children but can sometimes occur in adults.Signs and symptoms of type I diabetes often have a rapid onset. The most common indications are the three polys:Polyuria – excessive urinationPolydipsia – excessive thirstPolyphagia – excessive hungerOther signs and symptoms of uncontrolled diabetes are blurred vision, fatigue, paraesthesia (pins and needles or numbness), weight loss despite increased appetite and skin infections.Type I diabetes needs to be managed with insulin therapy. This used to be by self-injection, but many patients now have pumps which deliver regular doses. Management of type I diabetes includes careful management of food intake and exercise and matching the levels of insulin to requirements. This involves regular blood glucose tests which can be simply carried out with a thumb prick. The advantage of the pump system is that the patient is able to enter their blood glucose level into the pump and it automatically calculates the insulin dosage.16.1.2TYPE II DIABETESType II diabetes occurs when the level of blood glucose is high relative to the level of insulin produced. There are 3 main causes of type II diabetes:Insulin resistance – insulin is produced but it has less effect than normalLow production of insulin by beta cells Increased production of glucose by the liverOf these, the most common cause is insulin resistance. This is where the pancreas produces normal levels of insulin but the cells of the body become desensitised to it. This is often due to excessive carbohydrate intake. As the cells are presented with more glucose and insulin than they are able to handle, the number of receptors on the outside of the cells reduces so that they are less susceptible to the effects of the insulin. This means that more glucose remains in the blood. The pancreas detects the continued high blood glucose and produces yet more insulin. This leads to a vicious circle. Eventually the pancreatic cells get worn out with the effort of trying to produce enough insulin to cope with all the glucose. They get tired and less efficient – a bit like your muscles at the end of a long run. The result of all of this is long term raised blood glucose levels.Signs and symptoms of type II diabetes are similar to those for type I but they develop slowly over time and therefore are more difficult to recognise. A type II diabetic is also less likely to undergo a diabetic emergency.Type II diabetes occurs more often in adults than in children. It is often associated with a high calorie diet, particularly one high in carbohydrate, and a lack of physical activity. It tends to run in families but this could be due to lifestyle rather than genetics.Treatment for type II diabetes tends to centre around lifestyle modification:Low glycaemic index (GI) foods - these foods release their carbohydrates more slowly and therefore do not produce the characteristic swings in blood glucose and insulin levels that are associated with type II diabetesLow glycaemic load (GL) foods – not overwhelming the body with large quantities of carbohydrate at a timeIncreased exercise – exercise has been linked to decreased body fat, better weight control and increased insulin sensitivity.For those who are not able to manage their diabetes by diet and exercise alone, or who are not willing to make lifestyle changes, various medications are available. These can work by stimulating insulin production, increasing insulin sensitivity or decreasing liver glucose production. It is important to understand the cause of the type II diabetes before selecting the correct medication. For instance, there is no point in increasing insulin sensitivity if the hyperglycaemia is due to overproduction of glucose by the liver. 16.1.3GESTATIONAL DIABETESGestational diabetes is a type of diabetes that has its onset during pregnancy and resolves after childbirth. It most often happens in women with a family history of obesity, older mothers, women who have had multiple pregnancies and obese women. Gestational diabetes needs monitoring carefully as it can lead to pregnancy complications, miscarriage, stillbirth and foetal abnormalities. 16.1.4COMPLICATIONSComplications can arise from all types of diabetes. They can be divided into acute and chronic complications.Acute ComplicationsAcute complications are usually associated with type I diabetes but could also be associated with type II diabetes especially if they make sudden changes to exercise and medication.Ketoacidosis When insulin is critically low the body breaks down fats for fuel. The metabolic by-product of this is ketones which are highly acidic and lower the pH of the blood. This can result in nausea, vomiting, lethargy and fatigue. Eventually it can lead to hypotension and coma. Ketoacidosis is recognisable by a fruity odour to the breath. HypoglycaemiaHypoglycaemia occurs when blood glucose drops too low. This can be due to inadequate food intake, excessive insulin intake or vigorous physical activity. Symptoms include hunger, irritability, dizziness, sweating, confusion, weakness and loss of consciousness. Chronic ComplicationsThere are a number of long term complications that can result from diabetes particularly if it is poorly controlled. These complications apply to both type I and type II diabetes.The main complications associated with diabetes are:Cardiovascular disease – atherosclerosis, hypertension, stroke, peripheral vascular disease.Kidney disease – inflammation, lesions, loss of function, renal failure.Vision impairment –diabetic retinopathy, macular degeneration, cataracts, glaucomaNeuropathy – peripheral nerve damage, damage to spinal nerves, loss of sensation, numbness.Diabetic ulcers – mainly on foot, associated with either peripheral vascular disease or peripheral neuropathy. Can lead to necrosis or gangrene.Infections – increased risk of infection.16.2HYPERTHYROIDISM41935402095500Hyperthyroidism is a condition where the thyroid produces excess quantities of the hormones T3 and T4. The effect of these hormones is to increase metabolism and stimulate the sympathetic nervous system.Most cases of hyperthyroidism are caused by an autoimmune condition known as Graves’ disease. The immune cells attack the thyroid which causes it to swell up and form a goitre (swelling in the throat). Other causes include a pituitary tumour or excessive intake of iodine.Classic symptoms of hyperthyroidism, especially Graves’ disease, are the formation of a goitre and bulging eyes. The patient may also develop dry skin and thin, brittle hair and nails.Many of the signs and symptoms of hyperthyroidism are linked closely to the hypermetabolic state. They include nervousness, irritability, weight loss, increased appetite, tachycardia (high heart rate). Palpitations, shortness of breath, excessive sweating and heat intolerance. The person may also be fatigued due to inability to sleep. There are various treatments available for hyperthyroidism depending on the cause and severity of the condition:Medications to reduce thyroid functionReduction of dietary iodineSurgical removal of part or all of thyroidRadioactive iodine to destroy thyroidThere is a risk that the treatment of hyperthyroidism will result in hypothyroidism – a condition in which insufficient thyroid hormones are produced. 16.3HYPOTHYROIDISMHypothyroidism is a condition characterised by abnormally low levels of the thyroid hormones T3 and T4 in the blood. It affects about 10% of the population and is more common in women than men. There are two types of hypothyroidism:Congenital hypothyroidism – present at birthAcquired hypothyroidism – develops later in lifeCongenital hypothyroidism occurs when the baby is born with an abnormally small thyroid gland or without a thyroid. The condition may not be picked up immediately as the baby receives hormones from the mother while in the uterus. If not treated, the condition can result in mental retardation.There are a number of different causes of acquire hypothyroidism:Autoimmune – Hashimoto’s disease is an autoimmune condition that attacks the thyroid and stops it from functioningTreatment for hyperthyroidism – treatment with radioactive iodine usually results in hypothyroidismSurgery – surgical removal of thyroid due to hyperthyroidism or cancerMedications – including bipolar disorder medicationsRadiation exposure – including cancer treatment and other causesThe signs and symptoms of hypothyroidism are often subtle but increase as the condition persists. They include;Goitre (as thyroid enlarges to trap any available iodine)Fatigue and lethargyWeight gainSlow digestion with constipationPoor tolerance of coldDry skin and hairHigh cholesterolMuscle weaknessThe disease is treated with thyroid hormone replacement therapy.16.4CUSHING SYNDROME44386507048500Cushing syndrome is a condition that results from long term exposure to excess levels of cortisol and other glucocorticoids.Cortisol is a glucocorticoid hormone produced by the adrenal cortex. Its main function is the regulation of metabolism and stress response. It influences metabolism of glucose, fats and proteins in the body. Excessive amounts can also suppress the immune and inflammatory responses so glucocorticoids are prescribed to treat autoimmune and other inflammatory conditions.The manifestations of Cushing syndrome are: Weight gainIncreased abdominal fatAbdominal stretch marksRound faceBuffalo hump – fat between shoulder bladesMuscle wasting and weaknessIncreased bruisingThin skinAndrogenisation in women – male pattern hair growth and decreased menstruationHypertensionThe main causes of Cushing syndrome are long term stress, pituitary or adrenal tumour, or corticosteroid medication. Steroid medications can be given for a range of autoimmune and other conditions to reduce inflammation.Treatment of Cushing syndrome depends on the cause. Lifestyle changes can reduce stress-related cortisol levels. Review of corticosteroid medications can help to manage the condition. Where it is caused by a tumour, surgical treatment is usually required. 16.5ADRENAL INSUFFICIENCYAdrenal insufficiency is a condition where the adrenal glands fail to make enough hormones to meet the body’s demands. There are 2 main types of adrenal insufficiency:Primary insufficiencySecondary insufficiencyPrimary insufficiencyPrimary insufficiency is also known as Addison’s disease. It is caused by a gradual destruction of the adrenal glands due to an autoimmune disease, infection or tumour.Addison disease is a relatively rare condition. It usually has a slow progress and signs and symptoms often do not become apparent until about 90% of the adrenal gland is destroyed. Manifestations of adrenal insufficiency are those of a deficiency of the hormones it produces. Mineralocorticoid deficiency – urinary loss of sodium, chloride and water, potassium retention, decreased cardiac output, increased appetite for salt, hypotension, dehydration, weakness, fatigueGlucocorticoid deficiency – hypoglycaemia, poor stress tolerance, weakness, lethargy, gastrointestinal disturbanceAndrogen deficiency – limited symptoms due to production of hormones by testes and ovariesTreatment is with oral mineralocorticoid and glucocorticoid replacements. Patients should schedule regular times for diet and exercise because of hyponatremia and hypoglycaemia. They also have reduced ability to deal with infection, trauma and stress.Secondary insufficiencySecondary insufficiency occurs when the adrenal glands are not properly stimulated by the hypothalamus or pituitary gland. This can be due to any condition affecting the hypothalamus or pituitary, including cancer or infection, which affects the output of adrenocorticotropic hormone (ACTH) which stimulates the adrenals.A common cause of secondary insufficiency is the withdrawal of glucocorticoid medications such as cortisone. When these drugs are prescribed over a long period they suppress the normal function of the adrenal glands, leading to atrophy of the glands and reduced capacity to produce cortisol.When medication is withdrawn it takes time for the adrenals to adjust and start making sufficient quantities again. This is why people on steroid medications should always reduce dosage slowly and under medical supervision. LESSON 17 – NERVOUS SYSTEM DISORDERS17.1Headaches17.1.1Tension Headaches17.1.2Sinus Headaches17.1.3Cluster Headaches17.1.4Migraine Headaches17.2Meningitis17.3Seizures17.4Peripheral Neuropathy17.5Multiple Sclerosis17.6Cerebral Palsy17.7Parkinson’s Disease17.8Alzheimer’s Disease17.9 Sleep Disorders17.9.1Insomnia17.9.2Sleep Apnoea17.1HEADACHESHeadaches are one of the most common medical complaints affecting over 90% of the population. There are many different causes of headaches including vascular disorders, chemicals, hormonal imbalances, electrolyte disturbances of infection. A small number of cases can be attributed to more serious conditions such as meningitis, tumour or aneurysm but this is very rare.17.1.1TENSION HEADACHESTension headaches are the most common form of headache, accounting for about 90% of headaches. The name derives from the fact that they are often caused by muscle tension.Tension headaches can be described as a dull, aching, diffuse pain that feels like a hat band around the head. They are not usually associated with nausea and are not aggravated by activity.39979602603500Some of the major causes of tension headaches are:Tension in scalp or neck musclesOromandibular function (jaw muscles)Stress, anxiety or depressionCaffeineWithdrawal from analgesic medicationsDehydrationFatigueTension headaches can be treated with analgesics and non-steroidal anti-inflammatories (NSAIDs). Other medications used include antihistamines, sedatives and antidepressants.Other methods of treatment include massage to relieve muscle tension, relaxation, adequate sleep, hydration and avoidance of caffeine or other triggers.42233851651000017.1.2SINUS HEADACHESSinus headaches are caused by rhinosinusitis – an inflammation of the nasal passages and sinuses. Sinusitis can be caused by infection or allergy. Sinus headaches manifest as a frontal headache and facial pain. They can be treated with analgesics and NSAIDs. 45866052724150017.1.3CLUSTER HEADACHESCluster headaches are relatively uncommon, affecting just 1 in 100 people, most of whom are men. Cluster headaches occur in clusters – that is a number of recurrent episodes – over a few weeks or months before going into a period of remission. Each headache lasts 15-180 minutes, reaching its peak after 10-15 minutes of onset. They often happen at night. The pain usually occurs in the area surrounding the eye or in the temple and can be excruciating. It can also be associated with tears, nasal congestion, red eyes or sweating. The hypothalamus is believed to be somehow involved, but what causes or triggers cluster headaches is unknown. Because of the rapid onset and short duration, analgesics are largely ineffective at treating cluster headaches. Oxygen inhalation has been shown to help some sufferers. Prophylactic (preventative) medication can be used, and a wide range of medication types are used for this purpose. 17.1.4MIGRAINES4554855-444500Migraines are a throbbing, pulsating headache usually on one side of the head. It is more common in women than men. It is caused by a sudden cerebral vasoconstriction followed by an extreme vasodilation, causing a rush of blood to the head. The headache is often accompanied by nausea, vomiting, photosensitivity and sound sensitivity. It can last for 1-2 days and is exacerbated by physical activity.About 20% of migraines are preceded by an aura which can present as seeing stars or flashing lights, loss of vision, pins and needles, numbness or speech disturbance. The aura can last from 5 minutes to an hour.The exact cause of migraines is not fully understood. There appears to be a hereditary link in developing them as there is a family history in about 80% of cases. Hormonal changes, particularly oestrogen levels, can trigger migraine attacks, which is probably why they affect more women than men.Many people find that certain foods will trigger migraine attacks including cheese, wine, chocolate and monosodium glutamate. It is actually chemicals in the food that trigger the attacks not allergens.Treatment is aimed at preventative measures including avoiding triggers such as certain foods, getting enough sleep and avoiding stress. For people with recurrent severe migraines preventative medication can be used, usually antidepressants or sedatives.Symptoms can be treated with NSAIDs for headache and anti-emetics for nausea. Other classes of drugs including sumatriptans block the receptors in the brain. 17.2MENINGITISMeningitis is an inflammation of the meninges – the membrane surrounding the brain and spinal cord. It is most common in children under 5 years old and is caused by either viral or bacterial infection.411416543942000Risk factors for developing meningitis include age (very young or very old), head trauma, otitis media (ear infection), surgery, sinusitis, sepsis or immune deficiency.The manifestations of meningitis are usually more severe in bacterial meningitis than in viral. They include:Fever and chillsHeadacheStiff neckBack, abdominal and limb painPhotosensitivitySeizuresSome forms meningitis can present with a petechial rash. Petechiae are tiny bruises from the capillaries. This is not always present so should not be relied upon as a diagnostic sign. Confirmed diagnosis can be made by a lumbar puncture. If not treated quickly, meningitis can lead to permanent damage to the central nervous system. Treatment is usually with antibiotics and corticosteroids to reduce inflammation. Antibiotic therapy is usually started before the results of the lumbar puncture are obtained due to the risk to the patient. 17.3SEIZURESA seizure is an abnormal behaviour caused by erratic, uncontrolled electrical activity in the brain.There are some important definitions to remember when talking about seizures:Seizure – a discrete event with a set of signs and symptomsConvulsion – a particular type of seizure involving uncontrolled muscle movementsEpilepsy – a condition involving a series of repeated seizuresThere are many different types of seizures. They can be classified as:Partial – affecting part of the brainGeneral – affecting the whole brainThe main subtypes are summarised as follows:There are many different causes of seizures which include infection, tumour, injury, metabolic disturbance, drugs and congenital defects.During a seizure, the aim is to prevent the person from injuring themselves as much as possible and to seek medical help for prolonged seizures.Otherwise, there are two priorities – to identify and treat the cause of the seizures if possible and to prevent further seizures from taking place. Anticonvulsant medications can help in many cases. Surgical intervention can be used but this is a last resort.17.4PERIPHERAL NEUROPATHYPeripheral neuropathy is a condition involving damage to the peripheral nerves, usually the hands and the feet. Peripheral neuropathy is often associated with diabetes or alcoholism but it can be due to a wide range of different causes:DiabetesAlcoholism or drug abuseAutoimmune conditions – e.g. SLE, rheumatoid arthritisVitamin deficiencies including B12Toxins including arsenic, mercury or leadTraumaMechanical pressure e.g. carpal tunnel syndrome, herniated disc.Early manifestations are pins and needles, tingling, burning pain and hypersensitivity. This becomes replaced with numbness over time. Complications of peripheral neuropathy are muscle weakness and atrophy and paralysis. There is also a risk of secondary infection or ulcer as the patient is unaware of minor injuries. Foot ulcers are common in diabetics for this reason.Treatment depends on addressing the underlying condition to prevent further nerve damage. Special care needs to be taken to avoid infection and ulceration from injury. 17.5MULTIPLE SCLEROSISMultiple sclerosis is an autoimmune condition where the body’s immune system attacks the myelin that protects the nervous tissue in the brain and spinal cord causing inflammation and tissue destruction. Multiple sclerosis is usually diagnosed between the ages of 20 and 40 but it can also start later in life. It affects women more than men. Multiple sclerosis that starts later in life tends to have a slower progression.There are a wide range of signs and symptoms which are linked to the loss of neurological function including:Muscle weakness – loss of myelin sheath slows the nerve signalsMuscle spasm – chronic muscle stiffness or acute crampsChange in sensation – numbness or paresthesia (pins and needles)Loss of visionUrological dysfunction – difficulty urinating or incontinenceWalking difficulties – muscle stiffness, loss of coordination, numbnessCognitive dysfunction – loss of short term memory and learning abilityDigestive dysfunction – nausea, diarrhoea, constipation, swallowing difficultiesFatigueProgression of the disease is unpredictable. Many patients go through periods of decline followed by periods of remission. Others may have a continuous progressive deterioration.Much of the treatment is aimed at managing the symptoms of the disease. This involves muscle relaxant and analgesic medications, steroids and physical therapy. Interferon-beta medication can alter the effects of the disease to slow its progress.17.6CEREBRAL PALSYCerebral palsy (CP) is the name given to a group of movement disorders that can affect body movement, muscle control, muscle coordination, muscle tone, reflex, posture and balance.Some patients with CP also experience visual or hearing impairment, learning difficulties or epilepsy. CP is caused by damage to the central nervous system either before, during or after birth, which affects development. Causes include:Maternal illness or infection during pregnancyBirth trauma resulting in lack of oxygenTrauma to the brain in infancyCP is a non-progressive condition as the impairment does not significantly increase with age. However it is not reversible as damage to the central nervous system is permanent. The level of impairment can vary greatly. Some patients have very little impairment while others may be severely affected and unable to walk or possibly even feed without help.There are 4 types of cerebral palsy:Spastic CP –affects 80% of sufferers. Muscles activate incorrectly due to incorrect messages from damaged section of the brain. The muscles become stiff and tight. It is difficult to control and coordinate muscle movements.Dyskinetic CP – involuntary muscle movements such as twitching, twisting, repetitive movementsAtaxic CP – shaky movements. Problems with coordination and balance. Difficulty coordinating actions such as walking or picking up objects. Mixed CP – a combination of the above typesSigns and symptoms associated with the condition can vary according to the type and severity. They include:Tight, weak muscles“Heel walking” – tight calves stop patient from putting heels on the groundLack of coordinationSlow, slurred speechSlow development of motor skillsHip dysplasiaPoor balance and postureInvoluntary movements Vision or hearing impairmentUrinary incontinenceConstipation The condition cannot be reversed so treatment is aimed at managing the symptoms to maintain movement as much as possible. Key to this is physiotherapy and occupational therapy and speech therapy to assist with motor skills. Physical aids such as orthotics, walking frames or wheelchairs may be used as appropriate. Medications can be used to relax spastic muscles which improves movement and reduces pain.17.7PARKINSON’S DISEASEParkinson’s disease is a degenerative condition of the brain which affects the substantia nigra, the part of the brain that makes dopamine which is needed to produce smooth, controlled muscle movements. Parkinson’s disease usually begins after 50 years of age. The cause of the disease is unknown. The condition usually progresses slowly and does not significantly shorten life expectancy.The condition is characterised by tremor, muscle rigidity and bradykinesia (slow movement). The tremor is the most distinctive feature and usually starts as a rhythmic “pill rolling” movement in one hand before spreading to other limbs. It is most noticeable when the person is at rest and can lessen with conscious movement.Other symptoms that can develop include shuffling gait, indistinct speech, handwriting changes, sleep disorders, depression and slowed cognitive function.Two types of medication are prescribed to treat the condition – a precursor of dopamine which is converted to the active form in the body and drugs which stimulate the dopamine receptors in the brain. The medications are only effective for about 5-10 years because the brain develops and tolerance and they also have side-effects.Neurosurgery involving deep brain stimulation by electrode implants is becoming more common for patients who have severe side effects from dopamine therapy or for whom the therapy is no longer effective.17.8ALZHEIMER’S DISEASEDementia is a degeneration of the brain which affects thinking, behaviour, memory and ability to carry out everyday tasks. The most common type of dementia is Alzheimer’s disease which causes over 70% of dementia. Alzheimer’s disease is associated with age, which rarely affects people under the age of 65. The reason why Alzheimer’s develops is unknown. Alzheimer’s disease is characterised by the development of plaques and tangles within the brain.Plaques are a build-up of a sticky protein called beta amyloid in the brain. The amyloid plaques cause inflammation which damages the brain cells in the area of the plaque and cause scarring.Tangles result from the degeneration of long fibres called tau fibres which allow communication between areas of the brain. The fibres fray and become tangled. The development of plaques and tangles affects the ability of the brain cells to function normally and also to communicate with each other. Early signs of Alzheimer’s are loss of memory and difficulty finding the words to form sentences. Other signs and symptoms include:Memory loss, particularly short term memoryVagueness in everyday conversationLoss of enthusiasm for everyday activitiesSlowness in performing everyday tasksInability to recognise friends and relativesInability to process questions and instructionsDeterioration of social skillsEmotional instability ConfusionThere is no cure for Alzheimer’s however a class of drugs known as cholinesterase inhibitors can help neurotransmission and are particularly effective in helping memory loss. Other medications can be used to address some of the behavioural and emotional disturbances such as anxiety. 17.9SLEEP DISORDERSSleep disorders affect many people. There are a wide range of different sleep disorders which can be broadly divided into four categories:Hypersomnia – excessive daytime sleepiness not connected to night-time sleep patternsParasomnias – unusual behaviours during sleep including nightmares and sleepwalkingInsomnias – difficulty in falling asleep or staying asleepCircadian rhythm disorders – sleep patterns which do not fit into the 24 hour day-night cycle or with the social norm17.9.1INSOMNIAInsomnia is defined as having 3 or more of the following:Difficulty falling asleepDifficulty staying asleepWaking up too earlyPoor quality sleepNon-restorative sleepThe person must also have one of the following daytime symptoms:Fatigue or daytime sleepinessProblems with memory, attention or concentrationPoor social, academic or occupational performanceMood disturbance or irritabilityWorkplace or driving accidentsTension headachesAnxiety about sleepInsomnia can be associated with another medical condition or can exist on its own. There are many causes of insomnia including:Stress, anxiety or depressionHormonal imbalanceMedicationsAlcohol or caffeinePainEnvironmental factors – noise, light or temperatureCardiovascular or respiratory diseaseShift work or jet lagTreatment of insomnia includes:Quiet, comfortable sleep environmentDeveloping an evening routineRelaxation and stress managementAvoid caffeine and alcoholDo not exercise in the eveningAvoid large evening mealsAvoid day time napsGo to bed and rise at set timesMedications include anti-depressants and sedatives however many of them have side effects including day time sleepiness, anxiety and headaches. It is also possible to build up a tolerance to medications so that they no longer become effective.17.9.2SLEEP APNOEASleep apnoea is a disorder where a person regularly stops breathing during their sleep. Typical episodes last between 15 and 120 seconds and can occur up to 100 times a night. Sleep apnoea occurs when the upper airway collapses, usually at the level of the pharynx, obstructing the airway. All muscles in the body except relax when we sleep including the throat muscles. When the diaphragm expands the lungs, the negative pressure collapses the pharynx and sucks the tongue back into the throat which blocks the airway. Risk factors for developing sleep apnoea include:Sleeping on backNarrow airwayObesity or large neck girthAlcohol consumptionHypothyroidism AgeMale genderPost-menopausal womenThe fact that it is more prevalent in men and post-menopausal women suggests a hormonal factor.The effects on the body are those of lack of sleep and oxygen deprivation and include:SnoringInsomnia Day time sleepinessMorning headachesIrritability Hypertension Reduced cognitive functionTreatment for sleep apnoea includes behavioural changes such as losing weight, reducing alcohol consumption and changing sleep position. Oral or dental appliances can be used to move the tongue and mandible forward and prevent blockage of the airway. These can be fitted by an orthodontist.Patients can also use a continued positive airway pressure (CPAP) machine. CPAP provides constant supply of pressurised air via a mask which the person must wear over their mouth and nose while sleeping. The positive pressure helps to maintain an open airway. Some people do not like the machines and find that they are unable to sleep due to physical discomfort from the mask, noise, dry mouth or sense of claustrophobia.LESSON 18 – MENTAL ILLNESS18.1Mood Disorders18.1.1Depression18.1.2Anxiety18.1.3Bipolar Disorder18.2Disorders of Thought and Perception18.2.1Delusions18.2.2Hallucinations18.2.3Schizophrenia18.3Eating Disorders18.3.1Anorexia Nervosa18.3.2Bulimia18.3.3Compulsive Eating18.4Addiction18.1MOOD DISORDERSMood disorders affect our emotions. They are relatively common in our society but frequently go undiagnosed and untreated, often because of a perceived social stigma of seeking help.18.1.1DEPRESSIONDepression is a condition where a person experiences low mood, inability to experience pleasure, low self-worth and loss of interest in daily life for an extended period of time.In order to be classed as depression, the condition must last for at least two weeks, interfere with the ability to function and include at least 5 of the following criteria:There are many different causes of depression. Understanding what triggers it in any individual is key to helping them understand their condition and learn to deal with it. External factors – traumatic event, grief or loss, long term stress, loneliness or isolationGenetics – family history of depressive illness, genetic cause of chemical imbalance in the brainPersonality traits – higher tendency to develop depressionSerious medical illness – either due to the illness itself or the long term stress of dealing with itAlcohol or drug use – can both lead to and result from depressionHormone imbalance – pre-menstrual tension or post-natal depressionNutritional deficiencies – including vitamin D There are three main ways of treating depression:MedicationPsychotherapyLifestyle MedicationThere are many different medications to treat depression. The most commonly used are:Selective serotonin reuptake inhibitors (SSRIs) – block the reuptake of serotonin and so leave more of it circulating in the bodySerotonin noradrenaline reuptake inhibitors – block the reuptake of both serotonin and noradrenalinMonoamine oxidase inhibitors (MAOIs) – limits the action of an enzyme that breaks down neurotransmitters All of these medications have side effects which vary greatly from patient to patient. They include headaches, nausea, sleep disturbance, weight gain, dry mouth, sedation and dizziness. It is also possible to build up a tolerance to the medication.PsychotherapyThere are a number of techniques that can be used to help a person manage their depression:Cognitive behaviour therapy – helping the person to recognise thoughts and behaviours that contribute to their depression and change those thoughts and behaviours when they occurInterpersonal therapy – focussing on problems in personal relationships and ways to deal with themBehaviour therapy – encouraging people to undertake activities which are rewarding, pleasant or satisfyingMindfulness therapy – concentrating on the present moment, learning not to let their mind wander to the past or future or to unpleasant thoughts and feelingsLifestyle changesWhere possible, lifestyle changes can contribute to overcoming depression:Diet – following a healthy diet, avoiding sugar, caffeine and alcohol and increasing nutritional value particularly minerals and vitaminsExercise – activity helps depression by increasing serotonin and endorphin levels, improving sleep and helping to block or distract from negative thought patternsSocialising – keeping connected increases feelings of wellbeing, confidence and self-worthSupport groups – connecting with other people and sharing experiencesStress avoidance – avoiding stressful situations that can contribute to depressionRelaxation – meditation and other relaxation techniques help reduce anxiety which leads to depression18.1.2ANXIETYAnxiety disorders are characterised by a sense of fearfulness and worry that is not triggered by an event or is disproportionate to the situation, over a continuous period of time. They are the most common type of psychological disorder. People with anxiety disorders tend to see everyday situations as a potential threat or danger and as a result they live in a state of chronic stimulation of the sympathetic nervous system. Anxiety disorders involve an imbalance in the neurotransmitter chemicals in the brain. The imbalance often affects the limbic system which is responsible for processing memories and emotions. The neurotransmitters most affected are noradrenaline, gamma-aminobutyric acid (GABA) and serotonin.Some types of anxiety disorder such as post-traumatic stress disorder can be linked to a specific event however other types cannot be linked to anything specific and often have a genetic cause. There are often many different factors involved in developing an anxiety disorder. They can include:Family history of mental health issuesOngoing stressful events – e.g. job stress, living arrangements, family and relationship problems, abuse or trauma, grief or lossPhysical health problems – hormonal imbalances, serious illnessSubstance abuse – caffeine, alcohol, illicit drugsThe main types of anxiety disorder are:Generalised anxiety disorder – a constant feeling of chronic anxiety that lasts for 6 months or more. Symptoms include insomnia, fatigue, muscle tension and headaches. It often accompanies depression, substance abuse or other anxiety disordersPanic disorder – sudden onset of extreme sympathetic nervous symptoms including tachycardia, hyperventilation, chest pain, dizziness, fainting, sweating and a feeling of doomPost-traumatic stress disorder –the patient experiences flashbacks or nightmares of a traumatic event often triggered by everyday situations. Can cause withdrawal, irritability or aggression and hypervigilance as the person is wary of a repeat eventObsessive compulsive disorder – a combination of unwelcome, unpleasant, recurrent thoughts (obsessions) and the development of ritual activities (compulsions) to deal with the thoughts. Includes fear of dirt, germs or disorder. Compulsions can include hand washing, checking locks and compulsive organising.Social anxiety – irrational level of fear of being judged negatively by others or being embarrassed. Can result in agoraphobia (fear of going outside)Specific phobias – fear of specific things or situations e.g. spiders or heights. The fear is disproportionate to the situation.There are three main ways of treating anxiety:MedicationPsychotherapyLifestyle MedicationAntidepressant medications are often prescribed. They are described in the section above on depression. Some antidepressants can have side effects so they need to be monitored.Benzodiazepines are sedatives and are often prescribed for short term use to deal with anxiety or panic attacks. They can be addictive so are usually avoided for long term use. PsychotherapyThe two main types of psychotherapy used for anxiety disorders are:Cognitive behaviour therapy – helping the person to recognise thoughts and behaviours that contribute to their depression and change those thoughts and behaviours when they occurBehaviour therapy – encouraging people to undertake activities which are rewarding, pleasant or satisfyingInterpersonal therapy may also be appropriate for people with a social anxiety disorder.Lifestyle changesLifestyle changes to help cope with anxiety are very similar to those for depression:Diet Exercise Support groups Stress avoidance Relaxation 18.1.3BIPOLAR DISORDERBipolar disorder used to be known as manic depression because the patient experiences extreme mood swings from a state of mania to a deep depression. Mania is described as a state of euphoria and heightened energy. Manifestations include decreased need for food and sleep, irritability, racing thoughts, inability to focus and concentrate, rapid speech, inflated self-esteem, over-indulgence in pleasure, risk-taking and thrill-seeking behaviours and impaired judgement. Mania can develop slowly over days and weeks or the person can fluctuate between mania and depression during the same day. In extreme cases of mania, the person may experience delusions (false, irrational or illogical beliefs) or hallucinations (hearing, seeing or sensing things without external stimulation).What exactly causes bipolar disorder is not fully understood but there is a genetic factor with about 80% of sufferers having a family member with mental illness. There also appears to be a link with the regulation of serotonin levels. While other factors such as medical illness, stress or environmental factors may trigger or exacerbate the disease, they do not appear to be the primary cause. Treatment for bipolar disorder falls into two categories:Treatment of the current episode of mania or depressionPreventing future episodes from occurringMost people will require treatment with medication as well as psychotherapy. The type of medication required varies greatly between individuals and so the treatment regime must be carefully tailored and pliance with medication is often a problem. This can be because the person has trouble accepting their condition, because they enjoy the feeling of mania or because they find the side-effects of the medication unpleasant. Hospitalisation may be required in severe cases – where the person has a psychotic episode, fails to comply with their treatment regime or where the effects of the mania leave them too physically exhausted. 18.2DISORDERS OF THOUGHT AND PERCEPTIONThese are disorders which affect the way in which people receive, process and interpret sensory information which alters the way in which they are able to interact with the external environment.18.2.1DELUSIONSDelusions are a disorder of thought characterised by a persistent false belief from which they cannot be dissuaded. Delusions are influenced by a person’s family and social background, education and culture. They may include:Persecution – believing their person or property is being threatenedInfluence – e.g. believing that thoughts can move through radio wavesIll health – believing that they have a medical condition for which there is no evidenceGrandeur – believing they are Joan of ArcPossession – believing they are possessed by a ghost or demonThe reasons for delusions are unclear, but it is thought they may occur due to repeated stress rather than a one-off event18.2.2HALLUCINATIONSHallucinations are a disorder of perception where the person believes they are receiving sensory information in the absence of an actual external stimulus. There are many different causes of hallucinations including:Brain tumourEpilepsyMetabolic disorderDrug reactionsSensory deprivationSleep deprivation PsychosisMost hallucinations are either visual or auditory, but can also involve taste or smell. Another type of hallucination is phantom limb pain – where an amputee feels pain in the limb that no longer exists. 18.2.3SCHIZOPHRENIASchizophrenia is a condition involving disordered thought and language which is characterised by disorganised speech, delusions, hallucinations and possible catatonic behaviour. The condition usually first appears between 15 and 25 years of age. It is equally found in men and women and appears to have a genetic component with a 10x increase of likelihood in people with a family history.Delusions and hallucinations are both common in schizophrenia. Delusions can range from believing that someone is watching them to a belief that they are being controlled or manipulated by others.The hallucinations associated with schizophrenia are often auditory. They can range from simple repetitive sounds to multiple voices. The voices can be pleasant but are often angry and accusatory. Visual hallucinations are less common.The person may also display disorganised and incomprehensible speech patterns, reflecting the underlying disorganisation of their thoughts. The person with schizophrenia may also withdraw from social interaction, avoid speaking and display apathy and lack of motivation. There are a range of anti-psychotic medications available to treat schizophrenia. These medications can have side-effects including stiff or trembling muscles and involuntary movements. Antidepressant or sedative medication can reduce some of the side effects.Persuading the patient to continue taking their medication is one of the challenges of treating people with schizophrenia – either because of unpleasant side effects or because they do not feel like they need it. Psychosocial intervention is also important to help the person continue to function in society and also to help their family cope with the stress of living with someone with schizophrenia. 18.3EATING DISORDERSEating disorders are becoming more common and are affecting younger and younger people with increased exposure to negative body images through magazines, television and social media. 18.3.1ANOREXIA NERVOSAAnorexia nervosa is a condition involving distorted body image, obsession with losing weight and the belief that the person is fat even when they are dangerously underweight. It is most prevalent in girls and young women but is increasingly being seen in boys. It is most common in those involved in activities which have an expectation of a particular body type such as dancing, modelling or athletics. Behaviours displayed by someone with anorexia nervosa include obsessive dieting and fasting to minimise the number of calories entering the digestive system. This can often be accompanied by excessive exercise to burn off the few calories that are consumed. They may also use laxatives, diuretics or diet pills in an effort to lose more weight. The diagnostic criteria for anorexia nervosa are:Refusal to maintain a minimally normal body weight (BMI<17.5)Intense fear of gaining weight or becoming fatDistorted perception of body weight, size or shapeAmenorrhoea – loss of menstrual periods for at least 3 months.Anorexia is basically starvation, and the effects on the body are very similar:Treatment is difficult because the person often refuses to acknowledge that they have a problem. The goal of treatment is increased eating and weight gain which usually involves psychotherapy. In severe cases where the person refuses to accept help, they may need to be hospitalised for a period until their condition improves. 18.3.2BULIMIABulimia is a condition characterised by recurrent bingeing and purging (usually by vomiting) and is often accompanied by fasting and excessive exercise. It is most often seen among young women. Unlike anorexia nervosa, people with bulimia often maintain a body weight within or close to normal range so the condition is often difficult to detect. The diagnostic criteria for bulimia are:Recurrent binge eating – at least 2x per week for 3 monthsInappropriate compensatory activities – vomiting, diuretic or laxative abuse, fasting or excessive exerciseBehaviour influenced by body weight and shapeThe behaviour does not occur exclusively during periods of anorexia nervosaThe main complications of bulimia are linked to the frequent vomiting. They include damaged teeth, gum disease, oesophageal and stomach ulcers, dehydration and loss of electrolytes. Psychotherapy treatment can include cognitive behavioural therapy to change the thought and behaviour patterns around bingeing and purging. 18.3.3COMPULSIVE EATINGCompulsive eating, also known as binge eating disorder, is characterised by compulsive overeating beyond what is required to support the body’s metabolic needs. Compulsive eating differs from bulimia in that it is not accompanied by compensatory activities such as vomiting or exercise so the person rapidly gains weight. The eating may be in public or in private. Compulsive eating often develops as comfort eating as a way to deal with negative emotions or as a protection mechanism – hiding behind their weight. Binge eating often goes with other addictive behaviours. Diagnostic criteria for compulsive eating are binge eating for at least 2 days per week for at least 6 months and at least 3 of the following:Eating rapidlyEating until uncomfortably fullEating large amounts when not hungryDisgust, depression or guilt after eatingMany compulsive eaters will often go on a diet because they dislike the weight they have gained but they are unable to stick to it and so develop a pattern of yo-yo dieting.Treatment is based on psychotherapy, often cognitive behaviour therapy, to recognise the thoughts and behaviour patterns. Key to success is finding other ways of providing pleasure and comfort that can replace the food such as exercise. 18.4ADDICTIONAddiction comes in many guises. When we think of addiction, we usually think of illicit drugs, alcohol or tobacco. But it can cover so many things including prescription or over-the-counter medications. Many people are very good at hiding their addiction so family and friends may not even be aware that there is a problem. When talking about addiction, the medical terms used are substance use, substance abuse and substance dependency. It is important to understand the difference between the terms:Use is the use of a substance to create a change in mood or physical experience. It is not necessarily negative (e.g. two paracetamol for a headache does not usually cause harm).Abuse is the use of a substance to a level that does harm to the body and results in functional problems (e.g. drinking a whole bottle of wine at a party). Dependency occurs when the person is unable to control their use of the substance despite any negative consequences (e.g. smoking, alcoholism – where alcohol consumption impacts on health, family life or employment).Addictions do not always involve the consumption of physical substances. A good example of this is gambling – where the person gets addicted to the adrenalin rush. Addiction takes a great toll on the addict, their family and other people around them. The impacts can be on their physical or mental health, financial situation, employment, social or family life. The need to financially support the habit can often lead to crime. There are many different factors which contribute to the development of addiction. They include:Genetic pre-dispositionFamily or social situationStressPeer pressureDepressionPsychiatric illnessLong term use of prescription medicationMany addictive substances alter the production of and sensitivity to dopamine in the brain. They create a temporary increase in dopamine which produces a “high” however when this wears off the person can then be left feeling low which creates the desire for more of the drug. As they take it regularly they become desensitized to its effects which means they require greater quantities. Some substances also increase amounts of other neurotransmitters called glutamine and GABA.Treatment of addiction involves understanding what triggered the behaviour in the first place as well as the actions of the substance on the brain. This is important to avoid relapses in the future. There are specific medications to help with withdrawal from some substances such as methadone for heroin addicts. However the most effective form of treatment is psychotherapy including cognitive behavioural therapy, family therapy and support groups to help the person change their behaviour, cope with cravings and avoid behaviours which lead to relapse.BIBLIOGRAPHYAIDS Education and Training Centre, 2014, HIV Classification: CDC and WHO Staging Systems, US Department of Health and Human Services, USAAustralian Department of Health, 2014, Immunise Australia Program, Commonwealth of Australia, < et al, 1999, Pathologic Basis of Disease, 6th Edn, W B Saunders, USAClassification Criteria for Rheumatic Diseases, 2014, American College of Rheumatology, USA < Criteria_for_Rheumatic_Diseases/>Craggs-Hinton C, 2012, Coping with Eating Disorders and Body Image, 2nd Edn, Sheldon Press, UKCrofford L, 2013, Fibromyalgia, American College of Rheumatology, USA, < . 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