Retrospective analysis of Clostridium difficile infection in patients with ulcerative colitis in a tertiary hospital in China

BACKGROUND: Many reports have documented the increasing impact of Clostridium difficile infection (CDI) in patients with ulcerative colitis (UC). We conducted a retrospective study to determine the incidence, clinical characteristics, risk factors and prognosis of CDI in patients with UC. METHODS: We studied patients with UC, hospitalized between January 2010 and December 2015 in a tertiary hospital in China. Stool samples were tested for C. difficile toxins A and B (CDAB) by enzyme immunoassays in UC patients with disease flare. CDI in UC patients was diagnosed by clinical symptoms and positive CDAB test, and each case was matched with CDAB-negative patients in a 1:2 ratio. Univariate and binary logistic regression analyses were used to measure the differences between patients with and without CDI. RESULTS: Thirty-four (8.92%) of 381 patients with UC were CDAB positive. Antibiotic exposure within 3 months prior to the study (P = 0.004), hospitalization within 1 month prior to the study (P = 0.025), systemic use of steroids (P = 0.002) and active cytomegalovirus (CMV) infection (P = 0.001) were higher in CDI than non-CDI patients. Binary logistic regression analysis revealed that CMV infection was associated with CDI (odds ratio = 13.502, 95% confidence interval 1.307–139.512, P = 0.029). UC patients with C. difficile and CMV co-infection had more severe colonoscopic features. CONCLUSIONS: Recent use of antibiotics, prior hospitalization and systemic use of steroids increased the risk of CDI. CMV infection was an independent risk factor of CDI in patients with UC.