Common dermatophytes and in vitro anti-fungal susceptibility testing in patients attending the Dermatological Clinic at the Hospital for Tropical Medicine, Bangkok.

Dermatophytes comprising the genera Trichophyton, Microsporum, and Epidermophyton are important causes of superficial mycoses. The number of infected patients and the distribution of species of these organisms in our hospital were unknown. We therefore aimed to investigate the clinical pattern of dermatophyte infections and to identify the species of these dermatophytes at the Dermatological Clinic of the Hospital for Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok in a 1-year period. Twenty-six patients who had typical dermatophytosis lesions were recruited (27 specimens); 17 were female (65.38%) and 9 (34.62%) were male. The age range of the patients was 16-92 years. In total, nine dermatophyte isolates were identified by macroscopic and microscopic morphological characteristics. We found Microsporum canis (four isolates), Trichophyton mentagrophytes complex (one), Trichophyton rubrum (two), Trichophyton verrucosum (one), and Trichophyton tonsurans (one). The in vitro susceptibility profiles of seven antifungal agents against the nine dermatophytes were as follows (minimum inhibitory concentration ranges in μg/ml): The results were as follows (MIC ranges in μg/ml): ciclopirox, ≤0.06-0.5, griseofulvin ≤0.06-0.5, itraconazole ≤0.002-0.06, posaconazole ≤0.015-0.03, voriconazole ≤0.02-≥1, fluconazole ≤0.08-8, and terbinafine ≤0.01-0.125. This study represents the current state of dermatophyte infections in a metropolitan area of Bangkok, Thailand.