Wells' syndrome triggered by centipede bite

A 68-year-old African-American woman was awoken from her sleep by a centipede bite on the dorsum of her left hand. Several days later, the patient presented to the emergency room complaining of fevers, severe itching, swelling, and blistering (Fig. 1) of both hands. The past history was unremarkable. There was no history of asthma or use of medications. Physical examination at that time was consistent with a bullous cellulitis of the hands. Laboratory investigations revealed: white blood cell count (WBC), 10.3 (normal, 4-10.5); differential: 54 neutrophils, 15 lymphocytes, and 31 eosinophils. The platelet count was 225,000/mm³. A blood chemistry profile was within normal limits. Blood cultures and stool examination for ova and parasites were negative. The patient was treated with oral cephalexin and diphenhydramine.