Antifungal susceptibility testing for dermatophytes isolated from clinical samples by microbroth dilution method

ABSTRACT

Background: The cases of dermatophytoses have increased over the past few decades. Dermatophytoses affect the outer layers of skin, nails and hairs without tissue invasion. These infections are mostly not dangerous but, are important as public health problem particularly in the immunocompromised. The increased use of antifungal drugs for prolonged periods may lead to acquired antifungal resistance among previously susceptible strains. With this background present study was conducted to know the susceptibility pattern of dermatophytes.Methods: A total 35 isolates of dermatophytes isolated from clinically suspected cases of dermatophytoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species to antifungal agents- itraconaole, fluconazole and ketoconazole.Results: Itraconazole minimum inhibitory concentrations (MIC) varied from 0.0156 to 1 µg/ml for all dermatophytes. T. rubrum species showed higher MIC range for Ketoconazole than T. mentagrophytes and T. tonsurans. Fluconazole had poor susceptibility for all dermatophytes by having higher MIC values.Conclusions: The MIC values observed in present study will help clinician to select an appropriate antifungal agent with minimal side effects. The data from present study can be useful as reference for future studies covering large no. of isolates and more drugs.