Novel score predicts risk for cytomegalovirus infection in ulcerative colitis

•CMV can exacerbate ulcerative colitis and cause severe, refractory disease.•Activity and extent of ulcerative colitis are risk factors for CMV colitis.•Especially steroids and anti-TNF-α agents increase the risk of CMV induced colitis.•The risk of CMV colitis increases with the number of administered immunosuppressants.•The newly developed web-based score can aid in rapid exclusion of CMV colitis. Cytomegalovirus (CMV) infection is associated with relapse and exacerbation of ulcerative colitis (UC), especially in immunosuppressed patients. The aim of this study was to identify risk factors for CMV colitis and to develop a predictive risk score to estimate the probability of CMV colitis in UC patients supporting clinical decision making. A cohort of 239 UC-patients was retrospectively analyzed. Univariate and multivariate regression analysis identified several independent risk factors for CMV colitis and a predictive risk score was established using ROC analysis. CMV colitis is common in patients with severe ulcerative colitis. Clinical UC activity, disease duration and extent as well as the use of steroids and anti-TNF-α agents were identified as risk factors (p