A 46-year-old African American woman was admitted with a 3-month history of extensive macular, nonpruritic, erythematous rash on her upper chest wall. She also had bilateral proximal upper and lower extremity weakness. Her past medical history was significant for obesity, hypertension, and dyslipidemia.
Musculoskeletal examination revealed decreased muscle motor strength in both the upper and lower extremities but no sensory or cranial nerve deficits. The initial laboratory evaluations revealed leukocytosis (leukocyte count of 12.5 × 103/µL; normal, 3.4 to 9.2 × 103/µL); thrombocytosis (platelet count, 407 × 103/µL; normal, 142 to 405 × 103/µL); and elevated aspartate aminotransferase (71 U/L; normal, 15 to 37 U/L), alanine aminotransferase (81 U/L; normal, 12 to 78 U/L), creatine kinase (921 U/L; normal, 126 to 192 U/L), and aldolase (16 U/L; normal, 1.2 to 7.6 U/L) levels.
The patient's rash (top, left photograph) and her skin biopsy specimen (top, right photograph) and skeletal muscle biopsy specimen (bottom photographs) are shown.
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