Wofford College



Case 1: Hazel C. a 30-year-old female demonstrated a subtle onset of the following symptoms: dull facial expression; droopy eyelids; puffiness of the face and periorbital swelling; sparse, dry hair; dry, scaly skin; evidence of intellectual impairment; lethargy; a change of personality;?bradycardia?(low heart rate); hypotension (low blood pressure); constipation, and hypothermia (low body temperature.) The patient does not complain of pain.Lab Test Results:Plasma concentrations of total and free T4 and T3 follow:T4T3Total3 ug/dL (normal is 4-12 ug/dL)0.14 ng/dL (normal is 75-195 ng/dL)Free0.6 ng/dL0.01 ng/dLA blood sample indicated elevated TSH.?When TSH was infused intravenously, the output of thyroid hormones did not increase. Diagram the negative feedback loop that regulates the secretion of the thyroid hormones (TH), and include the names of the glands that secrete each of those hormones.How do Hazel's levels of T3 and T4 compare to normal? 3. What is the explanation for high levels of TSH and low levels of TH? Is the problem with the anterior pituitary or the thyroid gland?4. Is this a primary or secondary endocrine disorder? How can you tell?A biopsy of Hazel's thyroid revealed large numbers of lymphocytes in her thyroid gland and follicles much smaller than normal.5. What affect might these lymphocytes have upon thyroid function?6. Based on this information, name this particular endocrine disorder.7. What is the hormonal explanation for Hazel’s hypothermia??8. What is a likely explanation for Hazel’s bradycardia and hypotension? Is this a direct effect of low TH?9. Treatment with which of the following hormones would most quickly restore heart rate and blood pressure to normal: TH or EPI? 10. Describe a suitable hormone replacement treatment (HRT) for Hazel. Considering the chemical class of hormone, would this treatment require injections or capsules?? 11. Explain why treatment with a single hormone is expected to return body temperature, blood pressure and heart rate to normal.12. What is Hazel’s long-term prognosis? How long will she need HRT?Case2: Thomas L. a 28-year-old male, sustained a concussion during an athletic competition. He complained of abrupt onset polydipsia (excessive thirst) and polyuria (excessive urine volume). Blood and urine analyses provided the following results:Blood TestsUrinalysisFasting blood glucose 93 mg/dL(normal is 65-100 mg/dL)Serum sodium 145 mmol/L (normal is 135-145 mmol/L)Serum potassium 2.8 mEq/L (normal is 3.5-5 mmol/L)Urine osmolarity* <200 mOsm/L (much more dilute than normal)Urine volume 15 L/day (normal is 2-3 liters/day)Urine glucose 0 (normal is 0)Additional lab tests:Normal healthy persons respond to water deprivation and hypertonic saline infusion by producing a small volume of a concentrated urine. For Thomas, water deprivation and hypertonic saline infusion did not cause a significant reduction in the polyuria nor did the urine become more concentrated. Complete water-deprivation resulted in a urine osmolarity 225 mOsm/L, which is very dilute.Is Thomas hypoglycemic? How do you know?2. To maintain a steady state for water balance, how much water must Thomas drink per day? Additional test: Following administration of exogenous ADH, there was a dramatic increase in the concentration of Thomas’s urine and a decrease in urine volume. 3. The exogenous ADH test shows that Thomas’s kidneys are capable of producing a small volume of concentrated urine? What does this suggest about the root cause of his problem?4. What chemical class of hormone is ADH? In which gland it ADH synthesized? From which gland is ADH secreted? What are the target cells for ADH?5 Diagram the negative feedback loop for which ADH is the efferent pathway. Where are the receptors for this NFL and what is the stimulus that is being monitored by those receptors. What is the action of ADH upon the effector cells in the kidney?6. Given that Thomas’s symptoms appeared abruptly in the immediate aftermath of a concussion, what is the most probable explanation? 7. What is the name of this endocrine disorder? 8. Thomas was prescribed a nasal spray for self-administration containing a synthetic substance. What is active ingredient in the nasal spray? 9. Why was this compound given as a nasal spray? Why not have Thomas consume it in tablet form? 10. What is the long-term prognosis for Thomas? Must he take the nasal spray for the rest of his life? Why or why not? Case 3 Oscar T. a 45-year-old male from the Midwest presented with the following symptoms during February: weakness, fatigue, orthostatic hypotension (tendency to faint when going to a vertical position), weight loss, dehydration, and decreased cold tolerance. There was increased pigmentation (tanning) of both exposed and non-exposed portions of his body. Oscar’s blood chemistry values: Serum sodium 128 mEq/L (normal = 135-146 mEg/L)Serum potassium 6.3 mEq/L (normal = 3.5-5 mEq/L)Fasting blood glucose 65 mg/dL (normal = 65-100 mg/dL)Hematology tests:Hematocrit (Hct) = percentage of blood volume occupied by red blood cells.Oscar’s Hct = 50% (normal is 42-52%); Leukocytes 5000/cu mm (normal is 4300-10800/ cu mm)Plasma Cortisol: lower than normal.1. Is Oscar anemic? Which of the test results answers this question? 2. Does Oscar have an infection? Which of the test results answers this question? Additional testing: Following administration of exogenous ACTH, plasma cortisol did not rise significantly after sixty and ninety minutes. Endogenous circulating levels of ACTH were later determined to be significantly elevated. 3. Diagram the NFL that includes ACTH and Cortisol, naming the glands from which each is secreted.4. In a normal healthy person, how would plasma cortisol levels be affected by administration of exogenous ACTH? What do Oscar's ACTH test results imply? 5. Why is Oscar's endogenous circulating level of ACTH significantly elevated? 6. Is this a primary or secondary disturbance? Explain your answer. 7. What other hormones are secreted from the adrenal cortex? Is the sercretion of these hormones regulated by ACTH?8. Which adrenocortical hormone is most likely responsible for Oscar's serum electrolyte (Na+ and K+) imbalance? 9. Which adrenocortical hormone is most closely associated with the symptoms of weaknesss, fatigue, weight loss and decreased cold tolerance? 10. How is it possible for Oscar's plasma glucose to be within the normal range even though his cortisol levels are far below normal? Hint: Are their other hormones that contribute to glucose homeostasis?11. What is the name of this endocrine disorder? 12. How is Oscar’s splotchy hyperpigmentation in unexposed regions of skin related to his high levels of ACTH?13. If Oscar is treated with HRT, which hormone(s) would be required? Based on the chemical nature, can HRT be prescribed as a pill or must it be via injections? 14. Explain why we expect Oscar's abnormal pigmentation to resolve once his treatment has begun?15. What is the long-term outlook for Oscar? Case 4 Julian, a 21-year-old male, demonstrated the following:Poor muscle developmentHigh-pitched voiceMicrophallis= a stretched penile length of less than 2.5 standard deviations below the mean for age.Eunuchoidism = deficiency of sexual development (lack of fully developed reproductive organs and lack of facial and body hair. Essentially the persistence of pre-pubertal characteristics.Anosmia = the absence of sense of smellTall stature (6'7")Upon further questioning, it was found that Julian was born with a cleft palate, has only one kidney and cryptorchidism = one or both of the testes fail to descend from the abdomen into the scrotum. A blood sample revealed low serum levels of FSH, LH and Testosterone.1. A deficiency of which hormone most likely explains microphallis and eunuchoidism?2. Diagram the negative feedback loop that regulates that hormone and the other hormones and glands that involved.3. Describe the developmental abnormality involving the hypothalamus that is the root cause of Julian’s disorder and also explains his anosmia. 4. Name the endocrine disorder (be specific) in this case. Is this a primary or secondary disorder? What is the basis of your claim?6. In a normal healthy male, at what age does the growth of long bones end? What is the hormonal explanation for this cessation bone growth? How can Julian's tall be explained?7. Would HRT with testosterone alone alleviate all the symptoms? Why or why not?8. Will he be able to father children if left untreated? Why or why not? 9. Explain why you would recommend HRT that includes FHS and LH instead of testosterone.Case 5 Frankie D. 49-year-old female presented with the following symptoms: frequent headaches with impaired vision in both eyes, numbness and tingling sensation in hands, excessive sweating, increased shoe size from 8-10 inches and tightness of rings on fingers. On physical examination elongated head, prominent supraorbital ridges, enlarged nose, lips, ear, malocclusion of teeth, and husky voice were noted. Temp: 37°C, height 66 inches, foot 10 inches, hands 7.5 inches. Lab Results:GH: 29.8 (normal is 0-3 ng/mL)IGF-1: 811 (normal is 115-307 ng/mL)T3/T4/TSH/LH/FSH/Cortisol/Prolactin were within normal limits.Radiology Results:X-rays of the hands and feet show thickening of soft tissue, and increased joint spacing. Skull x-rays show enlargement of the frontal sinuses and sella turcica.Diagram the negative feedback loop that regulates the secretion of growth hormone, and include the names of the glands that secrete each of those hormones.How does the concentration of GH and IGF-1 compare to normal? Based on this finding, where is the dysfunction likely located? Is there more than one possible site?Is this a primary or secondary endocrine disorder? Briefly justify your response.What is the sella turcica? And what might cause enlargement of this brain region?Follow up Radiology Results:MRI of brain showed pituitary adenoma. Treatment options were discussed with patient. Patient was started on somatostatin analogue and referred to neurosurgery team for further management. What affect might an adenoma have upon pituitary function? Based on this information, name this particular endocrine disorder, and the cause of this disorder. What is the hormonal explanation for each of the following symptoms: enlarged hands and feet, coarsening of facial features, malocclusion of teeth, excessive sweating, and husky voice?What is the explanation for Frankie’s headaches, tingling and numbness in extremities, and visual impairment?How is it possible for a pituitary adenoma to affect growth hormone but not the other hormones synthesized and secreted from the anterior pituitary?What is the best treatment option for Frankie?Using the negative feedback loop for growth hormone, explain why the patient was started on a somatostatin analogue at diagnosis.What is the long-term outlook for the patient? Might one expect Frankie's changes in facial features and the size of the hands and feet to resolve once her treatment has begun? Explain. ................
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