Background: Risk factors associated with the development of pouchitis in adults after formation of an ileal pouch anal anastomosis (IPAA) include severe inflammation at diagnosis, upper gastrointestinal (UGI) involvement, backwash ileitis, pancolitis, and extra-intestinal manifestations (EIM), all of which are more common in paediatric-onset ulcerative colitis (UC). We thus aimed to assess outcomes and explore risk factors for pouchitis in children who underwent IPAA before the age of 18 years.
Methods: Data were retrospectively collected from 17 paediatric IBD centres from the Porto group of ESPGHAN. Electronic REDcap system was used, including explicit baseline characteristics, management, surgical information and medical short and long term follow up.
Results: A total of 129 children who underwent IPAA were included (50% male; 93% UC and 7% IBDU, mean age at diagnosis 10.5±4.2 years, median disease duration to colectomy 17 months (IQR 8–35.5 months) and median follow-up after pouch formation 36 months (IQR 21–64 months). Eighty-six children (67%) developed pouchitis during follow-up. In 33 (26%) the pouchitis was chronic, 10 of whom (8%) had Crohn's-like disease of the pouch. Median time from pouch formation to the first episode of pouchitis was 10.5 months (IQR 6–22); in 54% of cases the first episode occurred within one year.
The experience of the surgeon was strongly associated with development of chronic pouchitis (8/54 (15%) in surgeons with ≥10 surgeries/year vs 11/27 (41%) in surgeons with <10/year, p=0.013). There was no significant added benefit to surgeon experience greater than 10 surgeries/year.
Other variables that were associated with development of pouchitis included: younger age at diagnosis (mean 9.9±4.3 vs 11.7±3.7 years; p=0.014), longer disease duration prior to colectomy (median 22 (IQR 10–39) vs 13 (6–29) months; p=0.026), and Ashkenazi Jewish ethnicity (7/15 Ashkenazi patients with chronic pouchitis vs 21/103 patients of other ethnicity; p=0.046). The following variables did not predict pouchitis: UGI involvement, disease extent, backwash ileitis, EIM, pANCA positivity, IPAA type, and high PUCAI score at diagnosis/surgery). Multivariate logistic regression showed that chronic pouchitis was associated with male gender (HR=4.3, 95% CI 1.2–14.7) and surgeon experience (<10surgeries per/year) (HR=5.2, 95% CI 1.5–18.6) while controlling for age and disease duration.
Conclusions: UC patients who underwent IPAA during childhood developed pouchitis at a higher rate than usually described in adults. Surgeon experience seems to be an important controllable predictor of chronic pouchitis and should be taken into consideration in paediatric patients.