Isolation and Characterization of Clostridium difficile From 2 Geographically Separate Hospitals in Japan

Abstract

Background The epidemiology of Clostridium difficile is not well known in Japan because C. difficile cultures are not routinely performed. Methods We analyzed the toxigenicity and the polymerase chain reaction (PCR) ribotype of C. difficile strains isolated from 2 geographically separate hospitals in Japan. Results The results of PCR ribotyping of toxigenic C. difficile strains isolated from these 2 hospitals indicated that a single type (type smz) was predominant at hospitals located in diverse areas of Japan. Toxin A-negative, toxin B-positive (A-B+) variant C. difficile comprised 8 (18.6%) of 43 and 11 (16.4%) of 67 toxigenic C. difficile isolates from 2 hospitals, respectively. Of the 19 A-B+ strains, 18 (94.7%) showed the same PCR ribotype pattern (type z), which was identical to that of previously reported outbreak strains. Only 1 A+B+ strain possessed the binary toxin genes. Conclusion PCR ribotype smz, which has been reported as a responsible ribotype for multiple outbreaks at Japanese hospitals in the late 1990s, is still the major epidemic ribotype in Japan. PCR ribotype z strains of A-B+ variant C. difficile also have disseminated within Japan and represent a substantial proportion of C. difficile isolates.