[A case of choledochal cyst complicated by biliary peritonitis]

Choledochal cyst is a rare congenital malformation of the extrahepatic bile ducts. Its incidence varies among different populations, but it is highest in North East Asia. It is most frequent in childhood, and very rare in adults.

A 7-year-old boy was admitted to the hospital with severe abdominal pain under the right rib margin. He presented with constant nausea, occasional jaundice and high coloured urine. The following day the boy underwent ultrasound examination and computer tomography (CT). A choledochal cyst was found, and a CT-controlled puncture of the cyst was performed. An Xray was taken by injecting contrast medium through the drain. A small leakage into the abdominal cavity was observed with subsequent peritonitis. The general condition of the child deteriorated and a decision was made to operate immediately. An upper medial laparotomy was performed. A cystic formation was noted in the hepatoduodenal ligament of 90 x 70 mm in dimension. The cyst was completely removed and a hepaticojejunal anastomosis was performed The child tolerated the surgery well and recovered quickly.

Cystic dilation of the common bile duct, known as choledochal cyst, is related to a rare malformation of this region. The exact mechanism of cyst formation remains unknown. Choledochal cysts usually present in the early childhood, with higher frequency in females. The diagnosis is easily made, especially with the use of ultrasound and computed tomography. The treatment is usually surgical, and complete resection of the cyst with hepatico-jejunal anastomosis is the therapy of choice.

One year later, ultrasound examination and specific dynamic tests (HIDA) showed normal liver function, and good anastomosis.