Effect of Terminal Ileal Transposition on Gallbladder Bile Composition Following Proctocolectomy

Abstract

Enterohepatic circulation of bile acid is impaired and the percentage of secondary bile acids in bile decreases after proctocolectomy and ileo–anal anastomosis. Moreover, the site-specific function and morphology of the terminal ileum are likely to be damaged by acute and chronic inflammation because the ileum is being used as a reservoir in this procedure. A jejunal segment was interposed between the terminal ileum and the anus to spare the terminal ileum from being used as a reservoir following proctocolectomy in dogs. We performed this study to investigate the effects of this procedure on gallbladder bile lipid composition. Adult mongrel dogs underwent either terminal ileal transposition procedure (n= 7) or conventional ileo–anal anastomosis (n= 7) following two-stage proctocolectomy. The animals were laparotomized and gallbladder bile was collected 12 weeks later. In the terminal ileal transposition group, the total bile acid concentration significantly decreased (P< 0.01), while the secondary bile acid percentage did not. In the conventional group, the percentage of secondary bile acid significantly decreased (P< 0.05), while the total bile acid concentration remained unchanged. Proximal transposition of the terminal ileum may have an advantage in preserving the percentage of secondary bile acid in gallbladder bile. This procedure effects bile lipid metabolism differently than conventional ileo–anal anastomosis.