Definition

The term “choledochal cyst” is used to describe any congenital dilatation of the common bile duct (that carries bile from the liver to the intestine) or of the intrahepatic bile ducts. In many cases, a choledochal cyst develops when the common bile duct joins the pancreatic duct higher up than usual, i.e. before it flows into the intestine. This early junction creates a common canal that causes reflux of pancreatic juice into the bile duct, which results in irritation of the common bile duct and favours the development of a choledochal cyst. Long-term consequences may include bile duct cirrhosis and/or the development of bile duct cancer.
In Europe, the incidence is one case per 100,000 live births, and in Asia this figure is considerably higher.

 

Symptoms

Symptoms of choledochal cysts include attacks of abdominal pain, pancreatitis, jaundice and a mass on the right side. After childhood, the cysts may degenerate into carcinoma.


Diagnosis

Prenatal diagnosis is possible if there is considerable choledochal dilatation that is visible in prenatal ultrasound scans. The main risk is of confusing it with a cystic form of biliary atresia (cf. chapter on biliary atresia), which requires urgent treatment.

Postnatal diagnosis is also made by ultrasound when symptoms occur. Magnetic resonance cholangio-pancreatography (MRCP) is used for precise diagnosis of the morphology of the choledochal cyst

 

Treatment

Treatment is always surgical and needs to be performed early on to help avoid the development of hepatic fibrosis/cirrhosis or complications of the cyst such as pancreatitis or cholangitis (bile duct infection). Surgery involves the complete excision of the dilated common bile duct, which is at risk of developing cancer, and of the gallbladder; this is followed by bile duct reconstruction where a loop of the intestine is mounted to the liver.

 

Prognosis

Postsurgical results are good with clinical healing that is normally without consequences, and biological and ultrasound normalisation. However, long-term monitoring including an annual ultrasound scan is necessary.

 

 

Prof. Barbara Wildhaber
2014