WIDE DIVERSITY OF CLOSTRIDIUM-DIFFICILE TYPES AT A TERTIARY REFERRAL HOSPITAL

Nosocomial Clostridium difficile infection was investigated at a hospi tal with 15 cases of C. difficile diarrhea per 1000 discharges. From J anuary 1991 to May 1991, patients admitted or transferred to five ward s or units had weekly rectal swabs taken for culture; in addition, all cytotoxin-positive stools were cultured. Restriction enzyme analysis (REA) was used for molecular typing. Among 205 isolates from 39 patien ts with C. difficile diarrhea and 67 asymptomatically colonized, 55 di stinct REA banding patterns were identified. Evidence for patient-to-p atient transmission was limited, in that numerous strains were found e ven among clustered cases of diarrhea. Patients who acquired C. diffic ile in the community or other hospitals constituted 32% of culture-pos itive patients and contributed 44% of the REA types. Diversity of C. d ifficile strains was in part the result of patients acquiring C. diffi cile in the community or other hospitals. High incidences of nosocomia l C. difficile diarrhea do not necessarily indicate clonal epidemics.