A 58-year-old man who was taking chronic prednisone treatment for nephrotic syndrome presented with an 18-month history of multiple asymptomatic erythematous to violaceous nodules on the posterior left upper arm and forearm. He denied a history of fever, cough, fatigue, or other systemic symptoms. The patient noted the lesions shortly after being placed on 80 mg of daily prednisone to control his nephrotic syndrome, and reported that they increased in size as his prednisone was lowered to 60 mg daily. He denied preceding trauma to the area or recent travel outside of the country. Physical exam revealed multiple firm, nontender erythematous to violaceous nodules and papules on the posterior left upper arm and forearm, ranging in size from 1 to 3 cm. No drainage was noted. Two punch biopsies were obtained from the left arm and forearm and sent for histopathologic examination as well as tissue culture for bacterial, acid-fast bacterium, and fungal organisms.
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