De Novo Crohn's Disease of the Pouch in Children Undergoing Ileal Pouch-Anal Anastomosis for Ulcerative Colitis

Background: Approximately 10% of children with ulcerative colitis (UC) undergo colectomy with ileal pouch-anal anastomosis (IPAA). We aimed to describe the postoperative outcomes, with an emphasis on chronic pouch inflammation including de novo Crohn disease (CD) at a tertiary care inflammatory bowel disease center. Methods: Electronic medical records of all children who underwent colectomy ≤18 years between 2008 and 2017 were reviewed. Clinical and laboratory data were recorded. Primary outcome was frequency of chronic pouch inflammation including de novo CD. Secondary outcomes included early (≤30 days from index surgery) and late postoperative complications. Descriptive statistics (median and interquartile range) summarized the data and univariate analysis tested associations with outcomes. Results: Fifty-eight children underwent colectomy and 56 completed IPAA. Median age at diagnosis was 14 years (12-16.2) and at colectomy 16.2 years (14.2-17.7) with median follow-up of 13 months (5-43). Sixty-six percent underwent 3-stage IPAA and 78% were biologic exposed. Eleven had chronic pouchitis, 73% antibiotic refractory and 25% met criteria for de novo CD by median of 19 months (9-41). A total of 21% and 50% experienced early and late surgical complications, most commonly ileus and recurrent IPAA stricture. The pouch failure rate was 3.6%. Chronic pouch inflammation was associated with a later diagnosis of de novo CD (P = 0.0025). Conclusions: In pediatric UC, CD is not uncommon after IPAA. Chronic pouch inflammation often precedes a diagnosis of de novo CD. Families should be informed of the short- and long-term outcomes in children before UC surgery.