Case of Onychomycosis Caused by Microsporum racemosum

We report the case of a Spanish 60-year-old female who presented in 1997 with onychomycosis of the left thumbnail following an injury caused by a fresh fish bone. Microsporum racemosum was repeatedly cultured from nail scrapings, and its identity was confirmed by sequencing the isolate’s ITS1/ITS2 and 5.8S rRNA regions. The patient was successfully treated with itraconazole, which was administered for 12 weeks. This represents the first case of onychomycosis due to M. racemosum and the first time that this species has been isolated from a human in Europe.