Type-specific risk factors and outcome in an outbreak with 2 different Clostridium difficile types simultaneously in 1 hospital.

BACKGROUND Clostridium difficile infection (CDI) due to polymerase chain reaction (PCR) ribotype 027 (type 027) has been described worldwide. In some countries, an increase was reported of toxin A-negative PCR ribotype 017 (type 017). We encountered an outbreak due to these 2 types occurring simultaneously in a 980-bed teaching hospital in the Netherlands. METHODS In a case-control study from May 2005 through January 2007, we investigated general and type-specific risk factors as well as outcome parameters for CDI due to type 027 or 017. Clonal dissemination was investigated by multilocus variable number of tandem repeat analysis (MLVA). RESULTS We identified 168 CDI patients: 57 (34%) with type 017, 46 (27%) with type 027, and 65 (39%) with 1 of 36 different other types. As controls, we included 77 non-CDI diarrheal patients and 162 patients without diarrhea. Risk factors for CDI were nasogastric intubation, recent hospitalization, and use of cephalosporins and clindamycin. Type-specific risk factors were older age for both types 017 and 027, use of clindamycin and immunosuppressive agents for type 017, and use of fluoroquinolones for type 027. At day 30 of follow-up, the overall mortality among patients with types 017, 027, other types, non-CDI diarrheal patients, and nondiarrheal patients was 23%, 26%, 3%, 2%, and 6%, respectively. MLVA showed persistent clonal dissemination of types 017 and 027, despite appropriate infection control measures. CONCLUSIONS Patients with CDI have type-specific risk factors and mortality rates, with prolonged clonal spread of type 027 or 017.