OBJECTIVE: Failure after ileal pouch-anal anastomosis (IPAA) is reported with a frequency of 10-20%. The failed IPAA can be excised or defunctioned. Indications for excision and further management of an indefinitely diverted pouch are poorly described. The aim of the present investigation was to investigate pouch-related problems and the histopathological pattern of the pouch mucosa in this group of patients. METHOD: In a cohort of 620 patients having IPAA with a median follow-up of 14 years, 56 patients with failure were identified. The patients with defunctioned pouches were assessed with regard to pouch-related problems and endoscopy with biopsies was performed. Biopsies were stained with haematoxylin-eosin, PAS for neutral mucins and Alcian blue/high iron diamine for sialomucins/sulphomucins. Morphological changes were grouped into three types modified according to Veress and assessed for dysplasia. RESULTS: Twenty-two patients with an indefinitely diverted pouch were found. The follow-up time after surgery for failure was 10 years. Thirteen patients completed the follow-up. Except for two patients with pelvic/perineal pain, there were no clinical problems. The majority of patients displayed mild to moderate macroscopic signs of inflammation. Morphologically, findings ranged from a preserved mucosal pattern to intense inflammatory reaction. No case of dysplasia or carcinoma was found. CONCLUSION: Most patients with an indefinitely diverted pouch had no complaints regarding the pouch. There was no case of dysplasia. Indefinite diversion may be preferable to pouch excision, especially given the associated morbidity.