Estandarización del método de dilución en caldo para la determinación de susceptibilidad antifúngica in vitro de Trichophyton mentagrophytes y Trichophyton rubrum

Abstract

The increase in fungal infections and the appearance of new strains with antifungal resistance have made it necessary to develop methods for the determination of antifungal susceptibility, among the dilution is considered as the gold standard method for determination minimum inhibitory concentration (MIC), for this reason it is important that this method is carried out in a reliable way since it is the critical point for the choice of an appropriate therapy.

The present work proposed to standardize the broth dilution method for the determination of in vitro antifungal susceptibility of Trichophyton mentagrophytes and Trichophyton rubrum against different antifungals such as fluconazole, voriconazole, and itraconazole. The experimental work aimed at reproducing the antifungal susceptibility method described in the M61 of the Clinical and Laboratory Standards Institute (CLSI). The dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes were provided by the Microbiology Laboratory of the Chemical Sciences Faculty of the University of Cuenca (LMC-FQ).

As a result of this experimental work, a methodology for the development of in vitro antifungal assays in the standard working conditions of a research laboratory described in the M61 guide of the CLSI is presented. This technique will allow the development of guidelines for subsequent studies that evaluate the susceptibility of clinical strains to antifungals available for the treatment of dermatophytosis. It is also considered as the basis for further studies focused on the development of new antifungals of natural or synthetic origin.