Evaluation of an accelerated protocol for detection of extended-spectrum beta-lactamase-producing gram-negative bacilli from positive blood cultures

J Clin Microbiol. 2005 Jan;43(1):439-41. doi: 10.1128/JCM.43.1.439-441.2005.

Abstract

We evaluated a protocol for the accelerated detection of extended-spectrum beta-lactamases (ESBLs) in gram-negative bloodstream pathogens. Two hundred eighty-three blood culture bottles were subjected to direct ESBL testing by inoculating samples directly from blood culture bottles onto agar plates containing cefotaxime and ceftazidime disks, with and without clavulanate. Standard ESBL testing in accordance with the NCCLS guidelines after subculturing on agar plates was performed in parallel. Results of the direct ESBL testing were reported 2.3 days sooner and were comparable to those of the standard NCCLS method with sensitivity, specificity, and positive and negative predictive values of 100, 98, 94, and 100%, respectively.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Blood / microbiology*
  • Cefotaxime / pharmacology
  • Ceftazidime / pharmacology
  • Cephalosporin Resistance
  • Culture Media
  • Gram-Negative Bacteria / drug effects*
  • Gram-Negative Bacteria / enzymology
  • Gram-Negative Bacteria / growth & development
  • Gram-Negative Bacteria / isolation & purification*
  • Humans
  • Microbial Sensitivity Tests / methods
  • Predictive Value of Tests
  • Sensitivity and Specificity
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Culture Media
  • Ceftazidime
  • beta-Lactamases
  • Cefotaxime