Outcomes Following Infliximab Therapy for Pediatric Patients Hospitalized With Refractory Colitis–Predominant IBD

Abstract

Objectives While randomized trials demonstrated efficacy of infliximab for both pediatric Crohn’s disease (CD) and ulcerative colitis (UC), few patients in these studies exhibited colitis requiring hospitalization. The aims of this study were to determine the rate of subsequent infliximab failure and dose escalation in pediatric patients started on infliximab during hospitalization for colitis-predominant IBD, and to identify potential predictors of these endpoints. Methods Single center retrospective cohort study of patients admitted from 2005 to 2010 with Crohn’s colitis, UC, or IBD-unspecified (IBD-U) and initiated on infliximab. Results We identified 29 patients (12 Crohn’s colitis, 15 UC, and 2 IBD-U; median age 14 years) with a median follow-up of 923 days. 18 patients (62%) required infliximab dose escalation (increased dose or decreased infusion interval). Infliximab failure occurred in 18 patients (62%), due to ineffectiveness in 12 (67%) and adverse reactions in 6 (33%). 12 patients (41%) underwent colectomy. Subsequent need for infliximab dose escalation was associated with lower body mass index (BMI) z-score (P=0.01), lower serum albumin (P=0.03), and higher ESR (P=0.002) at baseline. ESR predicted subsequent infliximab dose escalation with an area under the curve of 0.89 (95% CI 0.72–1.00) and a sensitivity and specificity at a cutoff of 38 mm/hr of 0.79 (95% CI 0.49–0.95) and 0.88 (95% CI 0.47–0.99), respectively. Conclusions Most hospitalized pediatric patients with colitis treated with infliximab require early dose escalation and fail the drug long term. Low BMI and albumin, and high ESR may identify patients who would benefit from a higher infliximab starting dose.

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