Evaluation of the Vitek 2 System for Rapid Identification of Clinical Isolates of Gram-Negative Bacilli and Members of the Family Streptococcaceae

Eur J Clin Microbiol Infect Dis. 2002 Dec;21(12):869-74. doi: 10.1007/s10096-002-0826-x. Epub 2002 Dec 10.


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.

MeSH terms

  • Automation
  • Bacterial Typing Techniques / methods*
  • Bacterial Typing Techniques / standards*
  • Enterobacteriaceae / classification
  • Enterobacteriaceae / isolation & purification
  • Humans
  • Quality Control
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Streptococcaceae / classification*
  • Streptococcaceae / isolation & purification*