Severity of inflammation as a risk factor for ileo-anal anastomotic leak after a pouch procedure in ulcerative colitis

Purpose The pelvic pouch procedure (PPP) carries significant post-operative complication risks including a 4–14 % risk of ileo-anal anastomotic (IAA) leak [1–4]. The aim of this study is to evaluate the severity of disease at the distal resection margin as an independent risk factor for an IAA leak following the PPP for patients with ulcerative colitis (UC). Methods A retrospective matched case-control study was undertaken. The distal margin of each subject’s specimen was reviewed by a blinded pathologist and the degree of inflammation was scored using a modified histological activity index (mHAI)—a 0 to 5 graded scale with HAI of 5 representing ulcerations >25 % the depth of bowel wall. Results Forty-nine patients with perioperative IAA leaks (mean 11 days ±0.92) were identified and matched for gender, age and year of surgery. The case cohort had 33 males (67 %) of mean age at time of surgery of 36.3 years (±1.42). The severity of distal inflammation did not increase the risk of IAA leak. The presence of a diverting ileostomy was associated with a decreased incidence of an IAA leak ( p = 0.01). Conclusion Studies with greater power will be required to evaluate the association (if any) between histological severity of UC at the distal margin of a PPP procedure and IAA leak rate. This risk factor could influence preoperative management and post-operative outcome in patients requiring the PPP.