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

Toxigenic Clostridium difficile is the aetiologic agent of most cases of an tibiotic-associated diarrhoea and pseudomembranous colitis. The present sta ndard method for C. difficile diagnosis is a cytotoxicity assay, performed on human fibroblast cultures. It is time consuming and requires special fac ilities. A nested-PCR assay detecting toxin B gene within a few hours was d esigned. One hundred and two stool samples were collected during four month s. All samples were processed for toxin B-PCR, cultured for C. difficile an d 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, d oes not require special equipment and has produced excellent results. It de serves serious consideration for routine clinical microbiology laboratory u se.