2012) Time interval of increased risk for Clostridium difficile infection after exposure to antibiotics

Background: Clostridium difficile infections (CDIs) are common in developed countries and affect.250000 hospitalized patients annually in the USA. The most important risk factor for the disease is antibiotic therapy. Methods: To determine the period at risk for CDI after cessation of antibiotics, we performed a multicentre case–control study in the Netherlands between March 2006 and May 2009. Three hundred and thirty-seven hospitalized patients with diarrhoea and a positive toxin test were compared with 337 patients without diar-rhoea. Additionally, a control group of patients with diarrhoea due to a cause other than CDI (n227) was included. Results: In the month prior to the date of inclusion, CDI patients more frequently used an antibiotic compared with non-diarrhoeal patients (77 % versus 49%). During antibiotic therapy and in the first month after cessation of the therapy, patients had a 7–10-fold increased risk for CDI (OR 6.7–10.4). This risk declined in the period between 1 and 3 months after the antibiotic was stopped (OR 2.7). Similar results were observed when the second control group was used. All antibiotic classes, except first-generation cephalosporins and macrolides, were associated with CDI. Second- and third-generation cephalosporins (OR 3.3 and 5.3, respectively) and car-bapenems (OR 4.7) were the strongest risk factors for CDI. Patients with CDI used more antibiotic classes and more defined daily doses, compared with non-diarrhoeal patients