Biliary atresia is a blockage in the tubes (ducts) that carry a liquid called bile from the liver to the gallbladder.

Biliary atresia occurs when the bile ducts inside or outside the liver do not develop normally. It is not known why the biliary system fails to develop normally.

The bile ducts help remove waste from the liver and carry salts that help the small intestine break down (digest) fat.

In babies with biliary atresia, bile flow from the liver to the gallbladder is blocked. This can lead to liver damage and cirrhosis of the liver, which is deadly if not treated.

Newborns with this condition may appear normal at birth. However, jaundice (a yellow color to the skin and mucous membranes) develops by the second or third week of life. The infant may gain weight normally for the first month, but then will lose weight and become irritable, and have worsening jaundice.

Other symptoms may include:

• Dark urine
• Enlarged spleen
• Floating stools
• Foul-smelling stools
• Pale or clay-colored stools
• Slow growth
• Slow or no weight gain

The health care provider will perform a physical exam, which includes feeling the patient's belly area. The doctor may feel an enlarged liver.

Tests to diagnose biliary atresia include:

• Abdominal x-ray
• Abdominal ultrasound
• Blood tests to check total and direct bilirubin levels
• Hepatobiliary iminodiacetic acid (HIDA) scan, also called cholescintigraphy, to help determine whether the bile ducts and gallbladder are working properly
• Liver biopsy to determine the severity of cirrhosis or to rule out other causes of jaundice
• X-ray of the bile ducts (cholangiogram)

An operation called the Kasai procedure is done to connect the liver to the small intestine, going around the abnormal ducts. It is most successful if done before the baby is 8 weeks old. However, a liver transplant may still be needed.

Early surgery will improve the survival of more than a third of babies with this condition. The long-term benefit of liver transplant is not yet known, but is expected to improve survival.

• Infection
• Irreversible cirrhosis
• Liver failure
• Surgical complications, including failure of the Kasai procedure

Call your health care provider if your child appears jaundiced, or if other symptoms of biliary atresia develop.

A-Kader HH, Balistreri WF. Neonatal cholestasis. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 348.1.