An unusual case of onychomycosis due to Fonsecaea pedrosoi

Abstract

Onychomycosis is usually caused by dermatophytes, but some nondermatophytic molds and yeasts are also associated with invasion of nails. Here is a report of a case of distal and lateral subungual onychomycosis (DLSO) caused by Fonsecaea pedrosoi where it acts as primary agent of nail infection. Case reportA 30-year-old male presented with a 1-year history of brownish-black discoloration with hyperkeratosis on the finger and toenails. Scrapings were collected for smears and culture.Dematiaceous hyphae were seen on wet mounts of the scrapings and dark pigmented colonies grew repetitively on the culture media; all colonies were identical, and were subsequently identified as F. pedrosoi.In humid tropical regions F. pedrosoi is one of the primary causes of human chronic cutaneous mycosis, chromoblastomycosis. The case presented had certain unusual features. The disease was caused by an unusual fungus (Fonsecaea), occurred at an unusual site (nail) and in an immunocompetent individual.Combination of antifungal medications may provide the best option for cure in onychomycosis.