Detection of Clostridium difficile toxin A/B genes by multiplex real-time PCR for the diagnosis of C. difficile infection

J Med Microbiol. 2012 Feb;61(Pt 2):274-277. doi: 10.1099/jmm.0.035618-0. Epub 2011 Sep 29.

Abstract

Toxigenic Clostridium difficile culture is considered to be the standard diagnostic method for the detection of C. difficile infection (CDI). Culture methods are time-consuming and although enzyme immunoassay is rapid and easy to use, it has low sensitivity. In the present study, the AdvanSure CD real-time (RT)-PCR kit (LG Life Sciences) was evaluated for its ability to detect C. difficile toxin A (tcdA) and B (tcdB) genes, simultaneously. A total of 127 fresh diarrhoeal stool specimens, submitted to the clinical microbiology laboratory for C. difficile culture, were tested. C. difficile toxins and toxin genes were detected with a VIDAS C. difficile A&B (VIDAS-CDAB) enzyme-linked fluorescent immunoassay (ELFA) and the AdvanSure RT-PCR kit, respectively, according to the manufacturers' instructions. Their performance was compared with a standard toxigenic culture method as a reference. The sensitivity, specificity and positive and negative predictive values using the AdvanSure RT-PCR kit were 100 %, 98.3 %, 84.6 % and 100 %, respectively, while those of the VIDAS-CDAB system were 63.6 %, 100 %, 100 % and 96.6 %, respectively. Four tcdA(+)/tcdB(+) strains of C. difficile were detected with the AdvanSure RT-PCR kit, which offers comparable sensitivity and specificity to the reference method with a turnaround time of ~3 hours.

Publication types

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

MeSH terms

  • Bacterial Proteins / analysis*
  • Bacterial Proteins / genetics
  • Bacterial Toxins / analysis*
  • Bacterial Toxins / genetics
  • Bacteriological Techniques / methods
  • Clostridioides difficile / genetics
  • Clostridioides difficile / isolation & purification*
  • Clostridium Infections / diagnosis*
  • Clostridium Infections / microbiology
  • Enterotoxins / analysis*
  • Enterotoxins / genetics
  • Feces / microbiology
  • Humans
  • Molecular Diagnostic Techniques / methods*
  • Multiplex Polymerase Chain Reaction / methods*
  • Predictive Value of Tests
  • Reagent Kits, Diagnostic
  • Real-Time Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity

Substances

  • Bacterial Proteins
  • Bacterial Toxins
  • Enterotoxins
  • Reagent Kits, Diagnostic
  • tcdA protein, Clostridium difficile
  • toxB protein, Clostridium difficile