Candida glabrata: In vitro susceptibility of 84 isolates to eight antifungal agents

The in vitro susceptibility of 84 isolates of Candida glabrata from patients treated at the University Hospital of the Canary islands to eight antifungal agents (amphotericin B, itraconazole, fluconazole, miconazole, clotrimazole, tioconazole and econazole) has been studied using the broth dilution micro-method. Among the eight antifungal agents tested, the smaller geometric mean corresponded to tioconazole, econazole, clotrimazole and miconazole. In contrast with fluconazole, a greater geometric mean has been achieved. All the C. glabrata isolates tested were sensitive to concentrations of 3. 125 mu g/ml of clotrimazole and miconazole, 6.25 mu g/ml of amphotericin and ketoconazole. Concentrations of 12.5 mu g/ml were needed to obtain 100% inhibition of isolates for econazole and tioconazole and concentrations of 25 and 50 mu g/ml, respectively for itraconazole and fluconazole. Among our C. glabrata isolates, 2.4% were found to be resistant to amphotericin B. For fluconazole and itraconazole, 19.1% and 7.9% of isolates, respectively, were resistant. With reference to imidazoles, we obtained 2.4% and 3.6% resistance for tioconazole and econazole, respectively. No isolates were found to be resistant to ketoconazole, miconazole and clotrimazole. The results have shown a high activity of amphotericin B and itraconazole, observing a similar response with the five imidazole antifungals tested. The highest rate of resistance was found when fluconazole was used.