Risk factors for Clostridium difficile infection in the community: a case-control study in patients in general practice, Denmark, 2009-2011.

To identify risk factors for Clostridium difficile infection (CDI) in Danish patients consulting general practice with gastrointestinal symptoms, a prospective matched case-control study was performed; cases (N=259) had positive cultures for toxigenic C. difficile and controls (N=455) negative cultures. Data were analysed by conditional logistic regression. In patients aged 2 years (138 cases), hospitalization [odds ratio (OR) 84, 95% confidence interval (CI) 31-23], consumption of beef (OR 55, 95% CI 20-15), phenoxymethylpenicillin (OR 15, 95% CI 27-82), dicloxacillin (OR 27, 95% CI 36-211), and extended spectrum penicillins (OR 92, 95% CI 19-45) were associated with CDI. In patients aged <2 years none of these were associated with CDI, but in a subgroup analysis contact with animals was associated with CDI (OR 81, 95% CI 10-64). This study emphasizes narrow-spectrum penicillins, and suggests beef consumption, as risk factors for CDI in adults, and indicates a different epidemiology of CDI in infants.