Causes of failure and life expectancy of the ileoanal pouch.

180 ileoanal pouches constructed over 10 years and followed for at least 2 years (154 for Inflammatory Bowel Disease (IBD) and 26 for Familial Adenomatous Polyposis (FAP)) were reviewed. 23 pouches have been excised to date, 8 remain defunctioned (pouch failure FAP 7.7%, IBD 18.8%). The reasons for excision were: ischemia (n = 6), pelvic sepsis (n = 5), severe stenosis (n = 3), underlying Crohn's disease (n = 3), poor function (n = 5) and fistula (n = 1). The reasons for defunction were: Crohn's disease (n = 1), pelvic sepsis (n = 5) and ileoanal stenosis (n = 2). The projected overall pouch survival rate (Life table analysis) at 5 years was 81% (confidence interval 74-87%). Beyond 7 years, the figures to calculate survival became unreliable (small numbers). There was a significant association between pouch failure and pelvic sepsis (Fisher's exact test P < 0.0001) and between failure and fistula formation (P < 0.02). Multiple regression analysis showed pelvic sepsis and recurrent pouchitis to be independent factors of pouch failure. Pouch failure can occur many years after initial operation. Long-term follow up is recommended.