title: [A comparative study between the Vitek YBC and Microscan Walk Away RYID automated systems with conventional phenotypic methods for the identification of yeasts of clinical interest].
abstract: The aim of this study was to compare the identification of clin- ically relevant yeasts by the Vitek YBC and Microscan Walk Away RYID automated methods with conventional phenotypic methods. One hundred and ninety three yeast strains isolated from clinical samples and five controls strains were used. All the yeasts were identified by the automated methods previously mentioned and conventional phenotypic methods such as carbohydrate assimilation, visualization of microscopic morphology on corn meal agar and the use of chromogenic agar. Variables were assessed by 2 x 2 contingency tables, McNemar's Chi square, the Kappa index, and concordance values were calculated, as well as major and minor errors for the automated methods. Yeasts were divided into two groups: (1) frequent isolation and (2) rare isolation. The Vitek YBC and Microscan Walk Away RYID systems were concordant in 88.4 and 85.9% respectively, when compared to conventional phenotypic methods. Although both automated systems can be used for yeasts identification, the presence of major and minor errors indicates the possibility of misidentifications; therefore, the operator of this equipment must use in parallel, phenotypic tests such as visualization of microscopic morphology on corn meal agar and chromogenic agar, especially against infrequently isolated yeasts. Automated systems are a valuable tool; however, the expertise and judgment of the microbiologist are an important strength to ensure the quality of the results.
authors.affiliation: Departamento de MicologiáInstituto Nacional de Higíene Rafael Rangel, Caracas, Venezuela.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ferrara
authors.forename: Maria
authors.initials: M
authors.lastname: Mercedes Panizol
authors.forename: Marja
authors.initials: M
authors.lastname: Mazzone
authors.forename: Maria
authors.initials: M
authors.lastname: Delia Pequeneze
authors.forename: Vera
authors.initials: V
authors.lastname: Reviakina
mesh_terms: D001331:Automation; D003430:Cross-Sectional Studies; D006801:Humans; D016533:Mycological Typing Techniques / Q000379:methods*; D009181:Mycoses / Q000382:microbiology; D010641:Phenotype; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D016037:Single-Blind Method; D015003:Yeasts / Q000145:classification*
chemical_list: D011933:Reagent Kits, Diagnostic