Predictors of early response to infliximab in patients with ulcerative colitis

Background: Our objective is to report the outcome of infliximab (IFX) in ulcerative colitis (UC) patients from a single center and to identify predictors of early clinical response. Methods: The first 100 UC patients (45 female; median age, 37.9 years) who received IFX at a single center were included. Eighty-four patients received 5 mg/kg IFX, and 37 patients received a 3-dose lFX induction at weeks 0, 2, and 6. The Mayo endoscopic subscore, assessed by sigmoidoscopy before inclusion, was 1, 2, and 3 in 5%, 52%, and 43% of patients, respectively. Sixty percent had pancolitis, 63% were on concomitant immumosuppressive therapy, 9% were active smokers, 64% had C-reactive protein 5 mg/dL, and 44% were pANCA+/ASCA-. Five patients received lFX because of severe acute colitis refractory to intravenous corticosteroids. Results: Early complete and partial clinical responses were observed in 41% and 24% of patients. Patients with early clinical response were significantly younger than nonresponders (median age, 35.7 versus 41.6 years, P = 0.041). Patients who were pANCA+/ASCA- had a significantly lower early clinical response (55% versus 76%; odds ratio [OR] = 0.40 (0.16-0.99), P = 0.049). Concomitant immunosuppressive therapy and the use of an IFX induction scheme did not influence early clinical response. Only I of 5 patients who received IFX for acute steroid-refractory colitis required colectomy within 2 months. Conclusions: IFX is an efficient therapy in UC, as shown by 65% early clinical response. A pANCA+/ASCA- serotype and an older age at first lFX infusion are associated with a suboptimal early clinical response.