Trichosporon Species in Onychomycosis and Tinea Pedis / 대한피부과학회지

ABSTRACT

BACKGROUND: Onychomycosis and tinea pedis are common superficial fungal infections. Causative organism in onychomycosis and tinea pedis have been extensively studied, but the pathogenic role of non-dermatophyte is still controversial. Trichosporon species are soil and water-inhabiting yeasts, and occasionally found in the normal flora of human skin, mouth, and nails. Trichosporon spp. have been reported to be one of the pathogens in onychomycosis and tinea pedis. OBJECTIVE: We performed mycologic studies to investigate the prevalence and significance of trichosporon spp. in skin and nail lesions, which were clinically suspected of onychomycosis and tinea pedis. METHOD: We performed a survey of the mycologic laboratory records of patients clinically suspected of onychomycosis and tinea pedis from August 2001 to July 2002, and tried to identify trichosporon to species level by using API 20C kit systems. RESULTS: Out of total 1509 nail and skin samples examined, 663(43.9%) were culture positive. Trichosporon spp. were recovered from 11.2%(74/663) of the samples. In onychomycosis considered alone, the prevalence of solitary isolated Trichosporon spp. was 7.7%. In species level, T. asahii(62.1%), T. mucoides(20.3%), and T. inkin(14.9%) were isolated in decreasing frequency. The positive rate for KOH examination in trichosporon spp. was 52.9%. Among the isolated trichosporon spp., mixed cultures with other organisms were 13(17.6%) and solitary isolates were 61(82.4%). 31(41.9%) were not only positive for KOH examination but also founded in pure culture in relatively large colony counts. In pure culture isolations, high colony counts predominated over mixed cultures. CONCLUSION: Trichosporon spp. is a relatively common isolates from fungal cultures of skin and nail, and it may be pathogenic in some cases of skin or nail infection.