Evaluation of the VITEK 2 system (AST-YSO1 cards) for antifungal susceptibility testing against different Candida species

• Published in: Revista argentina de microbiología 2014-04, Vol.46 (2), p.111-118
• Main Authors: Ochiuzzi, María E, Arechavala, Alicia, Guelfand, Liliana, Maldonado, Ivana, Soloaga, Rolando
• Format: Article
• Language: Spanish
• Subjects: Amphotericin B - pharmacology; Antifungal Agents - pharmacology; Candida - drug effects; Fluconazole - pharmacology; Humans; Microbial Sensitivity Tests; Mycology - methods; Pyrimidines - pharmacology; Triazoles - pharmacology; Voriconazole
• ISSN: 0325-7541
• DOI: 10.1016/S0325-7541(14)70058-6

The aim of this investigation was to evaluate the results of antifungal susceptibility for various Candida species using the Vitek 2 semi-automated system (AST-YSO1 cards, bioMérieux), and to compare them with those obtained by the CLSI (Clinical and Laboratory Standards Institute) broth microdilution reference method (Document M27-A3,2008). The essential agreement (EA) was > 90%, except for Candida glabrata against voriconazole (VCZ); and for Candida krusei against fluconazole (FCZ). The overall categorical agreement (CA) was > 90% when FCZ was evaluated and 89.5% at 24h and 80.7% at 48 h for VCZ. The average time for obtaining results was 15.5h. Minor errors were 7.8% at 24h and 6.1% at 48 h for FCZ, and 10.5% at 24h and 19.3% at 48 h for VCZ. There was only one very major error for FCZ against Candida parapsilosis and no major errors were observed. For amphotericin B, only three isolates showed MICs ≥ 2 μg/ml. The Vitek 2 system detected the MIC value for various Candida species and showed excellent agreement with the reference method proposed by the CLSI.