A 21-year-old woman comes to the university health clinic ...

A 25-year-old man comes to the clinic complaining of an itchy rash for 2-3 weeks on his chest and upper back. He is otherwise healthy and is not taking any medications. On physical examination, there are numerous hypopigmented macules, some coalescing into patches on his chest wall, upper back, and proximal arms bilaterally. ................
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