Development of intrahepatic biliary stones after excision of choledochal cysts.

BACKGROUND The incidence of intrahepatic cholelithiasis and cholangitis has not yet been well studied postoperatively in patients with choledochal cysts. METHODS One hundred three patients with choledochal cysts had operative cholangiography, underwent standard excision of a choledochal cyst with Roux-en-Y hepatico-jejunal anastomosis, and were at a mean follow-up of 12 1/2 years. The incidence of intrahepatic bile duct stones was analyzed according to the 3 morphologic types of intrahepatic bile duct observed at initial operative cholangiography: type 1, no dilatation of the intrahepatic bile ducts; type 2, dilatation of the intrahepatic bile ducts but without any downstream stenosis; and type 3, dilatation of the intrahepatic bile ducts associated with downstream stenosis. Initially, there was no evidence of intrahepatic bile duct stones in any of the 103 patients. RESULTS Among 50 type 1 patients, intrahepatic cholelithiasis developed in only 1 patient (2%). Among 43 type 2 patients, 1 patient (2%) had intrahepatic cholelithiasis, and 2 (5%) had postoperative cholangitis. Among 10 type 3 patients, 4 (40%) had intrahepatic cholelithiasis (P <.01), and 3 (30%) had postoperative cholangitis. Time intervals between the initial surgery and the first identification of intrahepatic stones ranged from 3 to 22 years. CONCLUSIONS One of the major causes of formation of intrahepatic cholelithiasis has been clarified; patients with intrahepatic biliary dilatation with downstream stenosis can get intrahepatic bile duct stones long after excision of a choledochal cyst.