Coral-Red Fluorescence of Erythrasma Plaque.

Abstract

A 50-year-old man presented to the Department of Dermatology, University Hospital Complex of Granada, Granada, Spain, in 2015 with a slightly pruritic rash on the left groin, which he had had for two years. He had attended the hospital previously and been diagnosed with eczema and tinea cruris. This had been treated with topical steroids and antifungal drugs (methylprednisolone and sertaconazole) for several months without improvement. A physical examination of the patient showed a diffuse, brownish, well-defined, scaly plaque in the left inguinal region [Figure 1A]. A potassium hydroxide preparation of tissue scrapings was negative for fungal elements or cultures. The coral-red fluorescence of the plaque under a Wood’s lamp (WL) examination was characteristic of erythrasma [Figure 1B]. The patient was treated with 500 mg of oral erythromycin every 12 hours for 14 days, with progressive healing observed over three weeks. Figure 1A & B: A: Diffuse, brownish, well-defined, scaly plaque in the left inguinal region of a 50-year-old man. Note the ‘cigarette paper’ appearance. B: Wood’s light skin examination of the plaque showing bright coral-red fluorescence characteristic ...