Common bile-duct mucosa in choledochoduodenostomy patients--histological and histochemical study.

We describe the histological and histochemical changes of the common bile-duct mucosa in specimens obtained by means of peroral cholangioscopy, 1-12 years after choledochoduodenal anastomosis. Our findings--hyperplasia of the superficial epithelium, metaplastic goblet cells containing predominantly acid sialomucins, and pyloric-like gland formation containing neutral mucins--express a morphological and functional differentiation of the common bile-duct mucosa that probably facilitates its survival in a different environment. We consider that these adaptive changes may explain the uneventful long-term postoperative period of choledochoduodenostomized patients.