Caracterização fenotípica e molecular de leveduras isoladas em um hospital do Mato Grosso do Sul

Abstract

The correct identification of the isolates and determining the susceptibility profile are factors necessary for adequate therapy. The study evaluated the different techniques for identification of Candida species using the VITEK 2, CHROMagar Candida and Reaction Polymerase Chain (PCR). The automated system VITEK 2 was also evaluated for the determination of antifungal susceptibility together with the microdilution broth method. 81 samples of Candida were collected from March 2013 to March 2014. The identification of yeasts was performed by VITEK 2, CHROMagar Candida and PCR. The VITEK 2 showed 34.6% of misidentification. The CHROMagar Candida did not identify 14.8% of the isolates to the species level and 8.6% had errors in their identification. The PCR correctly identified 100% of the isolates and data were confirmed by sequencing the ITS region. The susceptibility profile antifungal was determined by the VITEK 2 and microdilution (MIC). 11.1% of isolates were resistant to amphotericin B (AMB), 4.9% to fluconazole (FLC) and 2.4% to voriconazole (VRC). The MIC, 7.4% of the isolates showed resistance and just the VRC. One isolate showed resistance VRC susceptibility in the two tested methods. 50% of isolates of Candida krusei was not identified by VITEK 2 and 50% of the isolates of the species presented as susceptible to CRF, which shows the importance of evaluating the two results before therapy. Therefore, the PCR is a fast, useful and accurate tool for identifying yeasts, but is not yet feasible for the hospital routine. The VITEK 2 is a valuable tool for identification and determination of antifungal susceptibility, but considering hospitals where there is low availability of resources, the CHROMagar Candida for laboratory identification of yeast species presented as a viable alternative because their results are as good as the automated system, with a lower cost-effective.