Predictors of 90-Day Colectomy in Hospitalized Patients Receiving Infliximab for Acute Severe Ulcerative Colitis at a Tertiary Care Center

BACKGROUND & AIMSAcute severe ulcerative colitis (ASUC) is a life-threatening presentation of ulcerative colitis requiring prompt treatment. Infliximab (IFX) rescue therapy can prevent colectomy in patients with ASUC. METHODSWe performed a cohort study of adult patients hospitalized with ASUC between 01/2014 - 02/2021 who received infliximab rescue therapy. Using multivariable logistic regression, baseline and longitudinal laboratory predictors of colectomy within 90 days of index hospitalization were identified and used to develop a risk prediction model and prognostic scoring system to identifying patients at risk for colectomy. Model performance was assessed using area under the receiver operator characteristic curve (AUC) analysis. RESULTS166 patients with ASUC who received infliximab rescue therapy were identified. Overall, 24.7% (n=41) underwent colectomy within 90 days. Multivariate analysis revealed that colectomy within 90 days could be predicted by having a calculated IFX clearance of >53L/d (OR 2.28, 95% CI 0.99, 5.22), a day 0 absolute C-reactive protein (CRP) > 91mg/L (OR 3.49, 95% CI 1.58 to 8.08), a decrease in CRP of < 43% from day 0 to day 3 (OR 4.13, 95% CI 1.84 to 9.94), and a decrease in CRP of < 9% from the day of IFX administration to one day post-IFX administration (OR 4.20, 95% CI 1.74 to 10.4). Using these predictors, two highly accurate prognostic scoring system were developed to identify patients at risk for requiring colectomy both prior to administering infliximab (AUC 0.76) and after administer infliximab rescue therapy (AUC 0.81). CONCLUSIONWe identified important baseline and longitudinal laboratory predictors of colectomy within 90-days among patients with ASUC receiving infliximab rescue therapy and developed accurate prognostic scores to determine risk of colectomy. These scores can be used risk-stratify patients and facilitate personalized management.