Nosocomial and non-nosocomial Clostridium difficile infections in hospitalised patients in Belgium - compulsory surveillance data from 2008 to 2010

Surveillance of Clostridium difficile infection (CDI) is compulsory in Belgian hospitals. Our objectives were to compare incidence and case characteristics of nosocomial infections (Nc-CDI) with onset of diarrhoea more than two days after hospital admission, with non-nosocomial cases (Nnc-CDI). The database included inpatients from 2008 to 2010. Of 8,351 cases reported by 150 hospitals, 3,102 (37%) were classified as Nnc-CDI and 5,249 (63%) as Nc-CDI. In 2010, the mean incidence per 1,000 admissions was 0.95 for Nc-CDI and 0.56 for Nnc-CDI. Both incidences were relatively stable over the three years, with a slight decrease in 2010 (p<0.01). Onset of symptoms in Nnc-CDI cases took place in the community (57.1%), nursing homes (14.2%) or hospitals (17.5%); data for 11.2% were missing. Nnc-CDI cases were younger than Nc-CDI (median age 75 vs. 79 years, p<0.001), and more likely to be women (62% vs. 57%, p<0.001) and to have pseudomembranous colitis (5.3% vs. 1.6%, p<0.001). In 2009, C. difficile ribotype 027 was found in 32 of 70 reporting hospitals compared with 19 of 69 in 2010 (p<0.03). Although our study population only included hospitalised patients, the results do not support the hypothesis of an increase in the incidence of severe community-associated CDI.