What is Biliary Atresia

Biliary atresia is a rare but serious disease of the liver that affects newborn infants. It occurs in about one in 10,000 children and is more common in girls than in boys and newborns Asian and African Americans than in Caucasian infants. Biliary atresia is the most common reason for liver transplantation in children in the United States and most of the western world.

Liver damage incurred by biliary atresia is caused by damage and loss (atresia) of the bile ducts, which is responsible for draining bile from the liver. Bile is made in the liver through the bile ducts and intestines where it helps digest food, fat and cholesterol. The loss of bile ducts causes bile to remain in the liver. When bile accumulates, it can damage the liver, causing scarring and loss of liver tissue. When the liver fails, a liver transplant becomes necessary. Biliary atresia can lead to liver failure and the need for a liver transplant in 1-2 years of life.

The pathology of the extrahepatic biliary system widely varies in these patients, and the following classification is based on the predominant site of atresia:

• Type I involves obliteration of the common duct; the proximal ducts are patent
• Type II is characterized by atresia of the hepatic duct, with cystic structures found in the porta hepatis
• Type III (>90% of patients) involves atresia of the right and left hepatic ducts to the level of the porta hepatis. These variants should not be confused with intrahepatic biliary hypoplasia, which comprises a group of distinct and surgically noncorrectable disorders.