Assessing the Impact of Interval Duration Between Ileal Pouch Creation and Loop Ileostomy Closure on the Development of Subsequent Inflammatory Pouch Conditions in Patients with Ulcerative Colitis.

Background: Many patients with medically refractory ulcerative colitis undergo ileal pouch-anal anastomosis, which typically includes the creation of a temporary loop ileostomy. The impact of the interval between ileal pouch-anal anastomosis and loop ileostomy closure regarding endoscopic pouch inflammation has not been well defined. The aim for this project was to assess if delayed loop ileostomy closure increases patients' risk of endoscopic pouch inflammation. Methods: This is a cohort study of patients with ulcerative colitis who underwent ileal pouch-anal anastomosis between 01/2010 and 12/2020. Patients were divided into groups-early (12-116 days) or late closure (>180 days)-based on interval between ileal pouch-anal anastomosis and loop ileostomy closure. The late closure group was further sub-divided by indication for delay which included post-operative complications and non-medical reasons. The primary outcome was development of endoscopic inflammatory pouch disease, which was a composite of pouch disease activity index score of ≥ 4, mucosal breaks beyond anastomotic lines, and diffuse pouch inflammation. Results: Two-hundred ninety patients were included which comprised early and late cohorts of 217 and 73 patients, respectively. Compared to early closure, late closures for non-medical and pouch-related surgical complications were both not found to be associated with development of our composite outcome ( Conclusions: Delaying ileostomy closure due to patient preference or logistical limitations did not result in an increased risk of endoscopic pouch inflammation, but there appears to be an association of extraintestinal manifestations with endoscopic inflammatory pouch disease, suggesting the need for a vigilant surveillance in these patients.