Evaluation of a novel molecular assay to diagnose toxigenic strains of Clostridium difficile

Anaerobe. 2018 Aug:52:111-114. doi: 10.1016/j.anaerobe.2018.06.012. Epub 2018 Jun 22.

Abstract

The objective of this study was to evaluate the Amplidiag C. difficile+027® assay, a new molecular method that detects toxin B gene in stool samples and identifies the hypervirulent 027 strain, to diagnose Clostridium difficile infections. The assay was compared to the reference method i.e. toxigenic culture. Amplidiag C. difficile+027® assay was prospectively evaluated from 309 diarrheal stool specimens of patients suspected of C. difficile infection. Forty-five (14.6%) stools were positive by toxigenic culture and 11 (3.6%) stools gave discordant results with the molecular method. PR027 was not recovered during the study. After resolving the discrepant results, the sensitivity, specificity, positive and negative predictive values of Amplidiag C. difficile+027® assay were 91.1% [CI 95% 77.9-97.1], 99.6% [CI 95% 97.6-100], 97.6% [CI 95% 85.9-99.9] and 98.5% [CI 95% 96-99.5], respectively compared to toxigenic culture. This assay is sensitive compared to the toxigenic culture.

Keywords: Clostridium difficile; Diagnosis; Molecular biology; Toxins.

Publication types

  • Evaluation Study

MeSH terms

  • Bacterial Toxins / genetics*
  • Clostridioides difficile / classification
  • Clostridioides difficile / genetics*
  • Clostridioides difficile / isolation & purification*
  • Clostridioides difficile / metabolism
  • Clostridium Infections / diagnosis
  • Clostridium Infections / microbiology*
  • Diarrhea / diagnosis
  • Diarrhea / microbiology
  • Feces / microbiology
  • Humans
  • Molecular Typing / methods*
  • Polymerase Chain Reaction / methods*
  • Prospective Studies
  • Sensitivity and Specificity

Substances

  • Bacterial Toxins