Rapid detection of toxigenic Clostridium difficile from stool samples by a nested PCR of toxin B gene

J Hosp Infect. 1999 Feb;41(2):145-9. doi: 10.1016/s0195-6701(99)90052-x.


Toxigenic Clostridium difficile is the aetiologic agent of most cases of antibiotic-associated diarrhoea and pseudomembranous colitis. The present standard method for C. difficile diagnosis is a cytotoxicity assay, performed on human fibroblast cultures. It is time consuming and requires special facilities. A nested-PCR assay detecting toxin B gene within a few hours was designed. One hundred and two stool samples were collected during four months. All samples were processed for toxin B-PCR, cultured for C. difficile and tested for cytotoxicity. This approach achieved 99% concordance with the cytotoxic assay. The sensitivity and specificity for the new PCR assay were 96.3% and 100% respectively. The procedure described is easy to perform, does not require special equipment and has produced excellent results. It deserves serious consideration for routine clinical microbiology laboratory use.

MeSH terms

  • Bacterial Toxins / genetics*
  • Bacteriological Techniques / standards
  • Clostridium difficile / classification*
  • Clostridium difficile / genetics*
  • DNA, Bacterial / genetics*
  • Feces / microbiology*
  • Humans
  • Polymerase Chain Reaction / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity


  • Bacterial Toxins
  • DNA, Bacterial