Quinolone use as a risk factor for nosocomial Clostridium difficile-associated diarrhea.

OBJECTIVE: To determine modifiable risk factors for nosocomial Clostridium difficile-associated diarrhea (CDAD). DESIGN: Case-control study. SETTING: 300-bed tertiary-care hospital. PARTICIPANTS: Hospital inpatients present during the 3-month study period. METHODS: Case-patients identified with nosocomial CDAD over the study period were compared to two sets of control patients: inpatients matched by age, gender, and date of admission; and inpatients matched by duration of hospital stay. Variables including demographic data, comorbid illnesses, antibiotic exposure, and use of gastrointestinal medications were assessed for case- and control-patients. Conditional logistic regression was performed to identify risk factors for nosocomial CDAD. RESULTS: 27 case-patients were identified and were compared to the two sets of controls (1:1 match for each comparison set). For the first set of controls, use of ciprofloxacin (odds ratio OR], 5.5; 95% confidence interval CI 95], 1.2-24.8; P=.03) was the only variable that remained significant in the multivariable model. For the second set of controls, prior exposure to cephalosporins (OR, 6.7; CI 95, 1.3-33.7; P=.02) and to ciprofloxacin (OR, 9.5; CI 95, 1.01-88.4; P=.05) were kept in the final model. CONCLUSIONS: Along with cephalosporins, prior quinolone use predisposed hospitalized patients to nosocomial CDAD. Quinolones should be used judiciously in acute-care hospitals, particularly in those where CDAD is endemic.