Echinocandin and triazole antifungal susceptibility profiles of opportunistic yeast and mould clinical isolates (2010-2011): Application of new CLSI clinical breakpoints and epidemiological cutoff values to characterize geographic and temporal trends of antifungal resistance.
J Clin Microbiol. 2013 May 29;
Authors: Pfaller MA, Messer SA, Woosley LN, Jones RN, Castanheira M
The SENTRY Antimicrobial Surveillance Program monitors global susceptibility and resistance rates of newer and established antifungal agents. We report the echinocandin and triazole antifungal susceptibility patterns for 3,418 contemporary clinical isolates of yeasts and moulds. The isolates were obtained from 98 laboratories in 34 countries during 2010-2011. Yeasts not presumptively identified by CHROMAgar, trehalose test or growth at 42°C and all moulds were sequence identified using ITS and 28S (yeasts) or ITS,TEF, and 28S (moulds) genes. Susceptibility testing was performed against 7 antifungals (anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole, voriconazole) using CLSI methods. Resistance rates to all agents were determined using the new CLSI clinical breakpoints and epidemiological cutoff values criteria, as appropriate. Sequencing of fks hot spots was performed for echinocandin non-wildtype (WT) strains. Isolates included 3,107 Candida (21 species), 146 Aspergillus (9 species), 84 C. neoformans, 40 other moulds (23 species), and 41 other yeasts (9 species). Among Candida, resistance to the echinocandins was low (0.0-1.7%). C. albicans and C. glabrata that were resistant to anidulafungin, caspofungin, or micafungin were shown to have fks mutations. Resistance to fluconazole was low among isolates of C. albicans (0.4%), C. tropicalis (1.3%) and C. parapsilosis (2.1%); 8.8% of C. glabrata were resistant to fluconazole. Among echinocandin-resistant C. glabrata isolates from 2011, 38% were fluconazole-resistant. Voriconazole was active against all Candida spp. except C. glabrata (10.5% non-WT) whereas posaconazole showed decreased activity against C. albicans (4.4%) and C. krusei (15.2% non-WT). All agents except for the echinocandins were active vs. C. neoformans and the triazoles were active vs. other yeasts (MIC90, 2 μg/ml). The echinocandins and triazoles were active versus Aspergillus (MIC/MEC90 range, 0.015-2 μg/ml), but the echinocandins were not active vs. other moulds (MEC90 range, 4->16 μg/ml). Overall, echinocandin and triazole resistance rates were low; however, fluconazole and echinocandin co-resistance among C. glabrata strains warrants continued close surveillance.
PMID: 23720791 [PubMed - as supplied by publisher]