Perniosis‐like tinea corporis caused by Trichophyton verrucosum in cold‐exposed individuals

Abstract

Trichophyton verrucosum is a zoophilic infectious agent causing 98% of the dermatophytic infections of cattle. Transmission to humans has, until recently, been rare. One reason for an increase of infection in humans and animals seems to be the decrease in immunisation of cattle. We report on three cases of pertinent human infections with disseminated, sharply defined, bluish red, partly oedematous nodules and plaques in particular not only on the thighs, but also on the trunk and arms. Two of our patients work with farm animals. The third one works as an assistant in a butcher shop, but lives on a cow farm. All three patients are often exposed to the cold. In all three cases T. verrucosum was detected by culture. Tinea corporis was histologically confirmed in two patients. Based on the microbiological results, we began a combined systemic and local antimycotic therapy with fluconazole 50 mg day(-1) in two patients, itraconazole 100 mg day(-1) in one patient p.o. combined with topical ciclopiroxolamine. All patients were cured. Dermatophytosis caused by T. verrucosum can, under certain circumstances, such as frequent exposure to cold or a long-term corticosteroid therapy, mimic the characteristic clinical picture of perniosis, as we demonstrate here.