Mucosal atrophy predicts poorer outcomes in pediatric ulcerative colitis - a national inception cohort study

Background: Outcomes in pediatric ulcerative colitis (UC) are heterogeneous and predictors of disease course eagerly sought. Mucosal atrophy (MA) is characterized by histological abnormalities of colonic intestinal glands. Objective: To determine the prevalence of MA in a national inception cohort of pediatric UC and its impact on outcomes. Methods: Irish children Results: Of 251 pediatric patients with UC (mean age 11.8 years, 55% male), 38 (15%) had MA on diagnostic biopsy. Baseline characteristics were similar between groups with/without MA and there was no difference in steroid-free remission or rates of moderate-severe UC at 1 year. Patients with MA had higher use of steroids (29% vs 15%, P = 0.04) and immunomodulators (40% vs 21%, P = 0.04) at 6 months, higher biologic use at 1 year (34% vs 16%, P = 0.03), earlier first relapse (mean ± SD 29.4 ± 26.1 vs 46.7 ± 43.4 weeks after diagnosis, P = 0.02), and higher colectomy rates by 2 years (21% vs 8%, P = 0.01). Conclusions: Children with MA at diagnosis had higher colectomy rates despite earlier treatment escalation and similar baseline severity scores. We identify MA as a promising new prognostic marker in children with newly diagnosed UC.</p