Korean J Dermatol.
2004 Jan;42(1):53-60.
Clinical Features and Identification of Etiologic Agents in Onychomycosis (1999-2002)
- Affiliations
-
- 1Department of Dermatology, College of Medicine, Dongguk University, Kyongju, Korea. mksuhmd@hanmail.net
- 2Department of Laboratory Medicine, College of Medicine, Dongguk University, Kyongju, Korea.
Abstract
- BACKGROUND
Although there have been many studies about tinea unguium, few studies about etiologic agents including nondermatophytic molds and yeasts in onychomycosis have been reported in Korea. OBJECTIVE: The purpose of the study was to investigate the recent clinical features and identification of etiologic agents in onychomycosis. METHODS: In the 3-year period 1999-2002, we reviewed five hundred ninty nine patients with onychomycosis in retrospectively. The etiologic agents were identified by cultures on Sabouraud's dextrose agar with and without cycloheximide. The identification of yeasts based on the results of culture, germ tube test, and biochemical API system tests. Nondermatophytic molds or yeasts isolated were considered as pathogens when the presence of fungal elements was identified at direct microscopy and follow-up specimen yielding cultures showed the same fungi. RESULTS: Of the five hundred ninty nine patients presenting with onychomycosis, 92.5% were toenail onychomycosis, 5.5% fingernail onychomycosis, and 2.0% onychomycosis in both toenails and fingernails. Among the age groups, the incidence rate was highest in the fifth decade(22.0%). The ratio of male to female patients was 1.1:1. Distal subungual onychomycosis(96.1%) was the most common clinical type of onychomycosis. In the toenail onychomycosis, dermatophytes were most frequently isolated(81.9%), followed by yeasts(11.7%), and nondermatophytic molds(6.4%). Trichophyton rubrum was the most frequently isolated agent. In the fingernail onychomycosis, yeasts were mostly isolated(48.2%), followed by dermatophytes(44.4%), and nondermatophytic molds(7.4%). CONCLUSION: Because of the increase in onychomycosis by nondermatophytic molds and yeasts, we suggest the need of a careful mycological examination in patients with onychomycosis.
