Erythema Multiforme in a Middle-Aged Woman

A 55-year-old woman had a 10-day historyof a nonproductive cough and apainful rash on both palms for 5 days.The eruption subsequently spreadover her entire body.Erythema multiforme--a reactivedermatosis exacerbated by a varietyof stimuli--was diagnosed. Thehive-like rash is more tender thanpruritic and features bull's-eye lesions.The 2 classic infectious causes areherpes simplex virus and Mycoplasmapneumoniae. Further evaluation ofthe patient confirmed the mycoplasmalsource; the infection responded toappropriate antibiotic therapy.The skin eruption improved dramaticallyafter a few days of systemiccorticosteroid therapy. (Case and photograph courtesy of Dr David L. Kaplan.)