Choledochal cyst originating from primary sclerosing cholangitis in a child.

Choledochal cysts are common in Asian children. Primary sclerosing cholangitis (PSC), which is characterized by inflammation and fibrosis and may lead to bile duct stricture over the intrahepatic or extrahepatic bile duct, is rare in children. Here we report a case of a 10-year-old boy who presented with a choledochal cyst originating from PSC. He had suffered from repeated abdominal pain and cholangitis for 3 years. A type IV choledochal cyst was suspected from the ultrasound and computed tomography image showing a distended gallbladder and dilatation of the bilateral intrahepatic duct at the hepatic hilar area and common bile duct (CBD). During laparotomy, a markedly distended gallbladder was noted and was shown to have no communication with the CBD by intraoperative cholangiogram. Choledochal cysts with extrahepatic and intrahepatic duct dilatation at the hilar area and marked stenosis with nearly total obstruction of the distal CBD were noted. Hepaticojejunostomy was performed. The histopathologic findings demonstrated a typical PSC picture. The patient's postoperative course was uneventful for 8 months after surgery, and he received no medication during a regular follow-up.