IN-VITRO SUSCEPTIBILITY OF CLINICAL YEAST ISOLATES TO FLUCONAZOLE ANDTERCONAZOLE

OBJECTIVE: Fifty clinical yeast isolates, representing equally Candida albicans, Candida krusei, Candida parapsilosis, Candida tropicalis, a nd Torulopsis glabrata, were tested in vitro for their susceptibility to terconazole and fluconazole. STUDY DESIGN: The minimal inhibitory c oncentrations of terconazole and fluconazole were determined by use of a proposed standardized broth macrodilution assay. Also, the response of selected yeast isolates to 25 mu g of either drug was measured by agarose disk diffusion experiments. RESULTS: For all species the minim um inhibitory concentrations for terconazole were significantly lower than those for fluconazole (p < 0.05). In fact, for each individual is olate the minimum inhibitory concentration of terconazole was consiste ntly lower than that of fluconazole. Differences in the geometric mean of terconazole and fluconazole minimum inhibitory concentrations were largest among C. krusei and T. glabrata, followed by C. parapsilosis, C. tropicalis, and C. albicans, in order of decreasing difference. Di sk diffusion experiments suggested that terconazole is a more effectiv e fungistatic agent than fluconazole is. CONCLUSION: Terconazole may b e more effective than fluconazole against yeast species other than C. albicans.