Evaluation of a real-time PCR assay for the detection of the Klebsiella pneumoniae carbapenemase genes in microbiological samples in comparison with the modified Hodge test

Am J Clin Pathol. 2011 Apr;135(4):566-71. doi: 10.1309/AJCPPVNUI3O9JHJW.

Abstract

Transfer of the bla(KPC) genes encoding the Klebsiella pneumoniae carbapenemase (KPC) are increasingly responsible for emerging carbapenem resistance. The modified Hodge test (MHT) is recommended for the detection of KPC. We compared MHT with a real-time polymerase chain reaction (PCR) assay targeting common subtypes of bla(KPC), using previously described forward and reverse primer sequences. The PCR product was detected using SYBR Green (Applied Biosystems, Foster City, CA) and confirmed by melt curve analysis. PCR was positive in 96% (52/54) of isolates that were MHT+, 90% (28/31) of MHT- isolates were PCR-, and the results were strongly correlated (P = .0001; Fisher exact test). The PCR assay is a sensitive, specific, and rapid test for detecting bla(KPC) genes. It could help optimize patient care by reducing the time taken to institute appropriate antimicrobial therapy and so help improve patient outcomes.

Publication types

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

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • DNA, Bacterial / analysis
  • Ertapenem
  • Genes, Bacterial / genetics*
  • Humans
  • Imipenem / pharmacology
  • Klebsiella Infections / diagnosis
  • Klebsiella Infections / drug therapy
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / enzymology
  • Klebsiella pneumoniae / genetics
  • Klebsiella pneumoniae / isolation & purification*
  • Microbial Sensitivity Tests / methods
  • Polymerase Chain Reaction / methods*
  • Predictive Value of Tests
  • beta-Lactam Resistance / drug effects
  • beta-Lactam Resistance / genetics
  • beta-Lactamases / genetics*
  • beta-Lactams / pharmacology

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • DNA, Bacterial
  • beta-Lactams
  • Imipenem
  • beta-Lactamases
  • carbapenemase-2, Klebsiella pneumoniae
  • Ertapenem