LAUSR

SE PRESENTATION CA A 39-year-old woman presented with a 2-week history of new-onset bilateral leg pain, arthralgias, and difficulty arising from bed. She reported a 2-day history of a pruritic rash on her right knee, right flank, posterior neck, and anterior scalp, along with a 3-day history of throat pain and fevers (daily maximum temperature, 39.48C). Laboratory values included white blood cell count, 11.1 (normal range [NR], 4-11) with 90% polymorphonuclear neutrophils (NR, 40-80%); platelets, 469 (NR, 150-450); ferritin 3,662 (NR, 12-300); erythrocyte sedimentation rate, 115 (NR, 0-29); C-reactive protein, 225 (#10); aspartate aminotransferase, 91 (NR, 10-40); alanine aminotransferase, 67 (NR, 7-56); negative antinuclear antibodies (ANA) and rheumatoid factor. Physical examination found excoriated, linear, and ill-defined violaceous papules and plaques (Fig 1). Biopsy of the flank revealed interface dermatitis (Figs 2 and 3).