Evaluation of a commercial microarray as a confirmation test for the presence of extended-spectrum β-lactamases in isolates from the routine clinical setting

Clin Microbiol Infect. 2011 Sep;17(9):1435-8. doi: 10.1111/j.1469-0691.2011.03567.x. Epub 2011 Jun 10.

Abstract

Since the diagnostic characteristics of the Check-KPC ESBL microarray as a confirmation test on isolates obtained in a routine clinical setting have not been determined, we evaluated the microarray in a random selection of 346 clinical isolates with a positive ESBL screen test (MIC >1 mg/L for cefotaxime or ceftazidime or an ESBL alarm from the Phoenix or Vitek-2 expert system) collected from 31 clinical microbiology laboratories in the Netherlands in 2009. Using sequencing as the reference method the sensitivity of the microarray was 97% (237/245), the specificity 98% (97/99), the positive predictive value 99% (237/239) and the negative predictive value 92% (97/105).

MeSH terms

  • Bacterial Typing Techniques / methods*
  • Bacterial Typing Techniques / standards
  • DNA, Bacterial / analysis
  • Enterobacteriaceae / classification
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae / genetics*
  • Enterobacteriaceae Infections / microbiology
  • Genes, Bacterial / genetics
  • Humans
  • Microarray Analysis / methods*
  • Microbial Sensitivity Tests
  • Polymorphism, Single Nucleotide / genetics
  • Predictive Value of Tests
  • Reproducibility of Results
  • Sequence Analysis, DNA / methods*
  • beta-Lactam Resistance / genetics
  • beta-Lactamases / genetics*

Substances

  • DNA, Bacterial
  • beta-Lactamases