Clostridioides difficile Infection Is Associated With Increased Colectomy Risk in Acute Severe Ulcerative Colitis Treated With Infliximab

BACKGROUND: Infliximab (IFX) is commonly used in the management of acute severe ulcerative colitis (ASUC), yet up to 30% of individuals still require colectomy within 1 year. Clinical data characterizing these patients, however, are limited. AIMS: We aimed to determine risk factors for colectomy among patients with ASUC who received in-hospital IFX treatment. METHODS: We performed a retrospective analysis of patients with ASUC who were treated with at least one dose of IFX while admitted between 2014 and 2022. Cox proportional hazards (PH) models were used to assess demographic, clinical, and laboratory risk factors for colectomy within 30 days and 1 year of IFX initiation. RESULTS: Overall, 36/170 (21.2%) patients underwent colectomy within 1 year of IFX initiation, with 22 (12.9%) individuals requiring colectomy within 30 days. On univariable analysis, concomitant Clostridioides difficile infection during admission, a ≤50% decrease in C-reactive protein (CRP) and experiencing 3 or more bowel movements per day within 48 hours after an initial IFX dose were significantly associated with 1-year colectomy. On multivariable Cox PH analysis, C. difficile infection during admission (aHR=2.92, 95% CI: 1.12-7.58) and a higher CRP/albumin ratio on admission (aHR=1.13, 95% CI: 1.01-1.27) were associated with increased colectomy risk within 1 year of IFX initiation. CONCLUSIONS: C. difficile infection and a higher CRP/albumin ratio on admission are associated with decreased time to colectomy within 1 year of IFX among patients presenting with ASUC. These factors may aid in early risk stratification to minimize delays in JAK-inhibitor initiation or surgical referral.