Poor Outcomes of Complicated Pouch-Related Fistulas after Ileal Pouch-Anal Anastomosis Surgery

Development of a pouch-related fistula tract is an uncommon but highly morbid complication to restorative proctocolectomy with ileal pouch-anal anastomosis. Pouch failure with permanent ileostomy is reported in 21%-30% of patients, yet the factors contributing to pouch excision remain poorly defined. The aim of this study was to determine the incidence and treatment results of complicated pouch-related fistula, as well as to evaluate factors involved in excision after pouch failure.

The study was conducted as a retrospective study. All patients with diagnosed pouch-related fistulas were registered with information related to fistula classification, treatments, and outcome.

The final analysis included 48 (10.7%) of the 447 total ileal pouch-anal anastomosis patients with complicated pouch-related fistulas. Pouch-vaginal fistulas, pouch-perianal fistulas, and other pouch-related fistulas were observed in 19 (63%), 29 (60%), and 10 (21%) patients, respectively, corresponding to an accumulated risk of 8%, 6%, and 2%, respectively. Time from ileal pouch-anal anastomosis surgery to fistula presentation was 24 (0.2-212) months. Overall pouch failure, defined as pouch excision or a diverting stoma, was seen in 34 (71%) patients, while pouch excision was seen in 23 (48%) of the patients. Patients who developed Crohn's disease had a significantly higher risk of pouch excision, as did patients with an early onset of the fistula after ileal pouch-anal anastomosis (P = 0.006 and P = 0.007, respectively). In conclusion, the present study demonstrated a high risk of pouch failure in patients with complicated pouch-related fistulas. Furthermore, it showed that Crohn's disease and the development of early onset fistulas are associated with pouch excision.