COMPARISON OF RESTRICTION ENZYME ANALYSIS, ARBITRARILY PRIMED PCR, AND PROTEIN PROFILE ANALYSIS TYPING FOR EPIDEMIOLOGIC INVESTIGATION OF AN ONGOING CLOSTRIDIUM-DIFFICILE OUTBREAK

During an outbreak of diarrhea in a general hospital in 1992, 166 Clos tridium difficile isolates From 102 patients were typed by restriction enzyme analysis (REA), arbitrarily primed PCR (AP PCR), and protein p rofile analysis (PP) techniques, A total of 18 types and 5 subtypes we re identified by REA, 32 types were identified by AP-PCR, and 9 types were identified by PP, Analysis of the data indicated the presence of a predominant strain among 76, 75, and 84% of the isolates by REA, AP- PCR, and PP, respectively. Subsequently, 45 C, difficile isolates whic h had been collected in 1990 from 33 patients in the same hospital fol lowing a significant increase in the number of cases of diarrhea cause d by C. difficile were studied by REA, AP-PCR, and PP typing technique s. Thirteen types and one subtype were identified by KEA, 12 types wer e identified by AP-PCR, and 5 types were identified by PP, As with the isolates from 1992, a dominant strain was identified. This strain was represented by 53, 64, and 70% of the total number of isolates when t he strains were typed by REA, AP-PCR, and PP, respectively, Every isol ate (210 of 211) from both 1990 and 1992 that was available for typing was typeable by all three methods. Furthermore, the same dominant str ain was identified in both 1990 and 1992 by each method. This study de monstrates that each of the three typing methods can be useful in epid emiologic investigations of C. difficile outbreaks and that one strain can be dominant in an institution over a number of years.