Endoscopic activity in asymptomatic patients with an ileal pouch is associated with an increased risk of pouchitis

Abstract

Background: The significance of endoscopic activity in asymptomatic ulcerative colitis (UC) patients with an ileal pouch is unknown.

Aim: To investigate the association of endoscopic pouch activity in asymptomatic patients with the subsequent development of pouchitis.

Methods: We analyzed a retrospective cohort of patients with UC or IBD-unspecified who underwent a total proctocolectomy with ileal pouch anal anastomosis (IPAA). Asymptomatic patients with a Pouchitis Disease Activity Index (PDAI) symptom sub-score of zero who underwent an index surveillance pouchoscopy were included. Endoscopic pouch body activity was graded as 0: normal, 1: mucosal inflammation, or 2: mucosal breaks (ulcers and/or erosions). The primary outcome was primary acute idiopathic pouchitis defined as PDAI score ≥ 7 with symptoms lasting less than four weeks and responsive to standard antibiotics, not otherwise meeting criteria for secondary pouchitis. The secondary outcome was chronic idiopathic pouchitis defined as PDAI score ≥ 7 with symptoms lasting greater than four weeks despite standard antibiotics. Predictors of pouchitis were analyzed using Kaplan-Meier and Cox regression methods with hazard ratios (HR) and 95% confidence intervals (CI) reported.

Results: 143 asymptomatic pouch patients were included. Index endoscopic pouch body activity was 0 in 86 (60.1%) patients, 1 in 26 (18.2%) and 2 in 31 (21.7%). The median length of follow-up after index surveillance pouchoscopy was 3.03 [IQR 1.24-4.60] years. Primary acute idiopathic pouchitis occurred in 44 (31%) patients and chronic idiopathic pouchitis in 12 (8.4%). Grade 2 endoscopic pouch activity was associated with the development of acute pouchitis (HR 2.39, 95% CI 1.23-4.67), although not chronic pouchitis (HR 1.76, 95% CI 0.53-5.87). Histologic inflammation in endoscopically normal pouch mucosa was not associated with acute or chronic pouchitis.

Conclusions: Mucosal breaks are present in nearly a quarter of asymptomatic patients with IPAA and are associated with an increased risk of acute pouchitis.