The Presence of Primary Sclerosing Cholangitis Is Protective for Ileal Pouch from Crohn's Disease

Background:Primary sclerosing cholangitis (PSC) has been shown to increase the risk for chronic pouchitis. However, the association between PSC and Crohn's disease (CD) of the pouch has not been studied.Methods:Consecutive inflammatory bowel disease patients undergoing proctocolectomy with ileal pouch-anal anastomosis in our Pouchitis Registry from 2002 to 2012 were studied. Cases consisted of patients with CD of the pouch. Both univariable and multivariable analyses were performed.Results:A total of 1425 patients met the inclusion criteria, including 265 (18.6%) with CD of the pouch and 78 (5.5%) with PSC. In the whole cohort, 799 patients (56.1%) were male and the mean ages at the time of diagnosis of inflammatory bowel disease and at pouch surgery were 25.5 12.3 years and 35.4 +/- 13.9 years, respectively. Patients with PSC had a longer duration from inflammatory bowel disease diagnosis to pouch construction (P < 0.001). Fewer patients with PSC had toxic megacolon at the time of colectomy (P = 0.009), but more patients with PSC had neoplasia as the indication for colectomy (P < 0.001), concurrent autoimmune disorders (P < 0.001), and liver transplantation (P = 0.001). In the multivariate analysis, the presence of PSC was shown to be inversely associated with the risk for the development of CD of the pouch, with a hazard ratio of 0.39 (95% confidence interval: 0.16 to 0.95, P = 0.038). However, no significant difference in terms of the distribution of phenotypes of CD of the pouch between patients with and without PSC was identified (P = 0.59).Conclusions:The presence of PSC is inversely associated with the development of CD of the pouch.