BACKGROUND: Resistance to antifungal drugs, especially towards triazoles, is commonly referred to by clinicians, but data on its prevalence in developing countries is limited. METHODOLOGY: To determine the prevalence of triazole-resistance amongst pathogenic yeasts and moulds, we assessed the in vitro susceptibility of 250 isolates from hospitalized patients at five Mexican cities towards amphotericin B, fluconazole and voriconazole, by E-test. RESULTS: All yeasts were susceptible to voriconazole, according to E-test interpretive criteria (MIC < or = 1 microg/mL), and all filamentous or dimorphic fungi also had voriconazole MIC < or = 1 microg/mL, except for one isolate each of Mucor sp. and Acremonium sp. Candida krusei and one isolate of C. glabrata were resistant to fluconazole, a drug that had MIC > or = 192 microg/mL for filamentous fungi. Although no breakpoints for amphotericin B are available, all three C. krusei, 2/25 C. glabrata, 3/22 C. parapsilosis and 1/108 C. albicans had MIC > or = 2 microg/mL. CONCLUSION: In vitro, voriconazole is active against yeasts and moulds commonly causing severe mycoses in Mexico.
BACKGROUND: Resistance to antifungal drugs, especially towards triazoles, is commonly referred to by clinicians, but data on its prevalence in developing countries is limited. METHODOLOGY: To determine the prevalence of triazole-resistance amongst pathogenic yeasts and moulds, we assessed the in vitro susceptibility of 250 isolates from hospitalized patients at five Mexican cities towards amphotericin B, fluconazole and voriconazole, by E-test. RESULTS: All yeasts were susceptible to voriconazole, according to E-test interpretive criteria (MIC < or = 1 microg/mL), and all filamentous or dimorphic fungi also had voriconazole MIC < or = 1 microg/mL, except for one isolate each of Mucor sp. and Acremonium sp. Candida krusei and one isolate of C. glabrata were resistant to fluconazole, a drug that had MIC > or = 192 microg/mL for filamentous fungi. Although no breakpoints for amphotericin B are available, all three C. krusei, 2/25 C. glabrata, 3/22 C. parapsilosis and 1/108 C. albicans had MIC > or = 2 microg/mL. CONCLUSION: In vitro, voriconazole is active against yeasts and moulds commonly causing severe mycoses in Mexico.