title: Evaluation of the Vitek 2 system for rapid identification of clinical isolates of gram-negative bacilli and members of the family Streptococcaceae.
abstract: Accuracy of the Vitek 2 automated system (bioMérieux Vitek, USA) for rapid identification of bacteria was evaluated using a collection of 858 epidemiologically unrelated gram-negative and 99 gram-positive clinical isolates. Isolates were tested after subculturing to ensure purity. Conventional agar-based biochemical tests (Steers replicator) were used as a reference method of identification. Gram-negative bacteria were identified to the species level with 95.3% accuracy by the system ( Enterobacteriaceae, 95.9%; and non- Enterobacteriaceae, 92.5%), and gram-positive isolates with 72% accuracy. Although Vitek 2 identified routine clinical isolates of gram-negative bacilli and Enterococcus faecalis and Enterococcus faecium reliably, rapidly, and reproducibly, improvement is required in the identification of less common species of enterococci and viridans group streptococci.
authors.affiliation: Department of Pathology, Northwestern Memorial Hospital and Northwestern University Medical School, Chicago, IL 60201, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Gavin
authors.forename: J R
authors.initials: JR
authors.lastname: Warren
authors.forename: A A
authors.initials: AA
authors.lastname: Obias
authors.forename: S M
authors.initials: SM
authors.lastname: Collins
authors.forename: L R
authors.initials: LR
authors.lastname: Peterson
mesh_terms: D001331:Automation; D015373:Bacterial Typing Techniques / Q000379:methods* / Q000592:standards*; D004755:Enterobacteriaceae / Q000145:classification / Q000302:isolation & purification; D006801:Humans; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013289:Streptococcaceae / Q000145:classification* / Q000302:isolation & purification*