Antifungal susceptibility of Candida species isolated from sterile sites of patients admitted in Srinagarind hospital

Abstract

The minimum inhibitory concentrations (MIC) and susceptibility patterns of Candida species isolated from sterile sites of patients in Srinagarind Hospital were determined. The 46 isolates of Candida spp. compose of 24 isolates of Candida albicans, 9 isolates of Candida tropicalis, 5 isolates of Candida parapsilosis, 5 isolates of Candida glabrata; 2 isolates of Candida spp. and 1 isolate of C. krusei. All isolates were tested for MIC determination against 7 antifungal agents; amphotericin B, fluconazole, itraconazole, ketoconazole, flucytosine, voriconazole and caspofungin by Sensititre YeastOne colorimetric antifungal panel. All C. albicans isolates were susceptible to fluconazole, flucytosine and voriconazole whereas 96 % of them were susceptible to itraconazole. Similar results occurred when tested with other Candida spp. All of Candida spp. isolates were susceptible to voriconazole. Susceptibility to fluconazole, flucytosine and itraconazole were 77%, 91% and 55% respectively. MIC₅₀ and MIC₉₀ of C. albicans against amphotericin B were the same concentration at 0.5 mg/ml, fluconazole were 0.25 and 0.5 mg/ml, itraconazole were 0.032 and 0.064 mg/ml, ketoconazole were the same level at  < 0.008 mg/ml; flucytosine were 0.12 and 0.24 mg/ml; voriconazole were the same level at  < 0.008 mg/ml and caspofungin were the same concertration at 0.06 mg/ml. MIC₅₀ and MIC₉₀ of Candida spp. to amphotericin B were the same concentration at 0.5 mg/ml; fluconazole were 1 and 16 mg/ml respectively. The results showed that the first choice of antifungal agents was voriconazole because of 100 % susceptibility against both C. albicans and Candida spp. The second choices were flucytosine and fluconazole.