TBA (22W105)

Mucosal Atrophy Predicts Poorer Outcomes in Paediatric Ulcerative Colitis- a National Inception Cohort Study.

Author(s)

Emily Stenke*1, Lorraine Stallard*1, Sarah Cooper2, Anna Dominik2, Abigail Pilkington1,3 Sheila Sugrue3, Maureen O’Sullivan2,4,5, Michael McDermott5, Shoana Quinn1, Annemarie Broderick1,2,6, Billy Bourke1,2,6, Séamus Hussey1,2,6,7, on behalf of the DOCHAS study2. * Emily Stenke and Lorraine Stallard are joint first authors

Department(s)/Institutions

1. National Centre for Paediatric Gastroenterology, CHI-Crumlin, Dublin, Ireland 2. National Children’s Research Centre, Crumlin, Dublin, Ireland 3. College of Sciences and Health, Technical University Dublin, Dublin, Ireland 4. Trinity College Dublin, Dublin, Ireland 5. Department of Pathology, CHI-Crumlin, Dublin, Ireland 6. School of Medicine, University College Dublin, Dublin, Ireland 7. Department of Paediatrics, Royal College of Surgeons of Ireland, Dublin, Ireland

Introduction

Outcomes in paediatric ulcerative colitis (UC) are heterogenous and predictors of disease course eagerly sought. Mucosal atrophy (MA) is characterized by histological abnormalities of colonic intestinal glands.

Aims/Background

To determine the prevalence of MA in a national inception cohort of paediatric UC and its impact on outcomes.

Method

All Irish children < 16 years old with UC are diagnosed CHI-Crumlin. At diagnosis, patients underwent phenotyping by Paris classification and activity assessment by PUCAI score. Biopsies from all colonic segments were evaluated for the presence of MA. Patients were followed prospectively. The primary outcome was corticosteroid-free remission at 1 year. Secondary outcomes included relapse, treatment escalation, and colectomy by 2 years.

Results

38/251 paediatric UC patients (15%) had MA on diagnostic biopsy (mean age 12.2 years, 71% male). 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 one year. Patients with MA had higher use of steroids (29% vs 15%, p=0.04) and immunomodulators (40% vs 21%, p=0.04) at six months, higher biologic use at one year (34% vs 16%, p=0.03), shorter times to first relapse (mean ± SD 26.5 ± 19 weeks vs 47.5 ± 43 weeks, p=0.002) and higher colectomy rates by 2 years (21% vs 8%, p=0.01).

Conclusions

Children with MA at diagnosis had higher colectomy rates despite having earlier treatment escalation and similar baseline severity scores. We identify MA as a promising new prognostic marker in children with newly diagnosed UC.