Significance of the anomalous arrangement of the pancreaticobiliary duct in the etiology of biliary atresia.

BACKGROUND/PURPOSE: The anomalous arrangement of the pancreaticobiliary duct (AAPBD) is one theory used to explain the etiology of biliary atresia. We investigated whether AAPBD could be involved and evaluated its significance for the etiology of biliary atresia.

MATERIALS AND METHODS

Of 43 patients with biliary atresia, the area between the common bile duct and the duodenum could be visualized by operative cholangiogram in 5 patients with an uncorrectable type of biliary atresia. Three of the 5 showed an anomalous arrangement of the pancreaticobiliary duct. In these 3 patients, the type of anomalous arrangement of the pancreaticobiliary duct and the length of the common channel were studied by operative cholangiogram. Histological findings of the gallbladder and the common bile duct were examined in addition to the measurement of the serum amylase levels.

RESULTS

All 3 patients showed AAPBD with the P-C type of pancreaticobiliary junction. The length of the common channel ranged from 7 mm to 12 mm. Two of the 3 cases did not show an elevated serum amylase level. Epithelial hyperplasia of the gallbladder was observed in one patient, while the other two showed no hyperplasia. Inflammatory changes in the mucosa of the gallbladder and the common bile duct were not remarkable in these 3 patients.

CONCLUSIONS

From these results it seems that AAPBD in biliary atresia might not be an etiological factor for atresia of the extrahepatic bile duct, but might be an associated anomaly in biliary atresia. Other factors should be examined to clarify the etiological factor leading to lumenal obstruction of the extrahepatic bile duct.