PCR AMPLIFICATION OF RIBOSOMAL-RNA INTERGENIC SPACER REGIONS AS A METHOD FOR EPIDEMIOLOGIC TYPING OF CLOSTRIDIUM-DIFFICILE

From January to March 1993, a suspected outbreak of antibiotic-associa ted diarrhea occurred on a pediatric oncology ward of the Clinical Cen ter Hospital at the National Institutes of Health. Isolates of Clostri dium difficile obtained from six patients implicated in this outbreak were typed by both PCR amplification of rRNA intergenic spacer regions (PCR ribotyping) and restriction endonuclease analysis of genomic DNA . Comparable results were obtained,vith both methods; five of the six patients were infected with the same strain of C. difficile. Subsequen t analysis of 102 C. difficile isolates obtained from symptomatic pati ents throughout the Clinical Center revealed the existence of 41 disti nct and reproducible PCR ribotypes, These data suggest that PCR riboty ping provides a discriminatory, reproducible, and simple alternative t o conventional molecular approaches for typing strains of C. difficile .