Onychomycosis in Iran: epidemiology, causative agents and clinical features.

Background: Onychomycosis represents the most frequently encountered nail disease, which is difficult to eradicate with drug treatment. Aim: This study was undertaken to document the clinico-mycological pattern of onychomycosis in Iran. Results of mycological tests of nail scrapings collected over a 4-year period were analyzed. Methods: Both direct microscopy and cultures of the nail material were performed to identify the causative agents. Results: The microscopic and/or cultural detection of fungi was positive in 40.2% of samples. The most common clinical type noted was distolateral subungual onychomycosis in 48.4% of cases. Etiological fungal agents were 50% dermatophytes, 46.8% yeasts, and 3.2% saprophytic moulds. The most frequently detected dermatophyte species were Trichophyton rubrum (48.4%) and T. mentagrophytes (41.9%). Among yeasts, Candida albicans (58.6) was most common, followed by C. parapsilosis (17.2%), C. glabrata (10.3%), C. krusei and C. tropicalis (each 6.9%). Aspergillus niger and A. flavus were the most frequent saprophytic moulds. Females were affected more frequently than males, and in both sexes those most infected were between 40-49 years of age. Fingernails were affected more frequently than toenails. Conclusions: The clinico-epidemiological data collected can serve as reference for future research and may be useful in the development of preventive and educational strategies.