Case–Control Study of Inflammatory Bowel Disease Patients with and without Clostridium difficile Infection and Poor Outcomes in Patients Coinfected with C. difficile and Cytomegalovirus

Background and Aims Clostridium difficile infection (CDI) incidence and risk factors in patients with inflammatory bowel disease (IBD) have been extensively studied. However, data describing CDI in Chinese patients with IBD are limited. We investigated the cumulative incidence, risk factors, and outcomes of CDI in Chinese IBD patients. Methods We conducted a retrospective, case–control study of patients hospitalized with IBD and CDI at Peking Union Medical College Hospital from January 2010 to December 2015. CDI was diagnosed based on the presence of active symptoms and positive enzyme immunoassay-based stool test results for C. difficile toxin A or B (CDAB). Controls were selected from CDAB-negative patients with IBD and matched by age, gender, phenotypes of IBD and the same time period of CDAB testing at a 1:2 or 1:3 ratio. Results We identified 60 (7.41%) cases of CDI among 810 patients with IBD, and 137 control cases were selected. Univariate analysis revealed that IBD patients with CDI had higher rates of concurrent corticosteroid use, proton pump inhibitor, antibiotic use, recent hospitalization, parenteral nutrition support, and cytomegalovirus (CMV) coinfection ( P < 0.05). Multivariate analysis revealed that concurrent corticosteroid use (odds ratio [OR] = 6.803, 95% confidence interval [CI] = 2.901–15.954, P < 0.001) and hospitalization within 1 month (OR = 3.028, 95% CI = 1.225–7.480, P = 0.016) were associated with CDI. CMV and C. difficile coinfection (hazard ratio [HR] = 4.185, 95% CI = 1.492–11.736, P = 0.007) as well as disease severity (HR 2.070, 95% CI = 1.006–4.261, P = 0.048) were independently associated with colectomy following CDI. Conclusions IBD patients with concurrent corticosteroid use and recent hospitalization are at a higher risk of CDI. CMV and C. difficile coinfection is associated with poorer outcomes.