What Is Biliary Atresia?

Biliary atresia is a rare disease of the bile ducts that affects only infants. Bile ducts are pathways that carry a digestive fluid called bile from the liver to the small intestine. Once there, it breaks down fats and absorbs vitamins. It then filters waste out of the body.

With biliary atresia, these ducts swell and become blocked. Bile is trapped in the liver, where it starts to destroy cells. Over time, the liver can be scarred -- a condition called cirrhosis. Once this happens, it can't filter out toxins the way it should.

Some babies get it in the womb. But most often, symptoms appear between 2 and 4 weeks after birth.


Doctors believe a number of things may trigger biliary atresia, including:

  • Change in a gene
  • Problem with the immune system
  • Problem with the way the liver or bile ducts develop in the womb
  • Toxic substances
  • Viral or bacterial infection after birth

It isn't passed down from one family member to another, and babies can't catch it from someone else.

Girls who are born prematurely are most at risk. So are Asian and African-American babies.


If your baby has biliary atresia, one of the first things you'll notice is that her skin and the whites of her eyes look yellow. This is called jaundice. Jaundice is very common among infants, especially in those born before 38 weeks, but it usually goes away in 2 to 3 weeks. Jaundice caused by biliary atresia lasts longer than that.

Her abdomen also may swell, she'll have gray or white stools, and her pee will be dark. This happens because her liver can't process bilirubin -- a reddish-brown substance that's made when red blood cells break down. It's what gives poop its brown color.

Some babies also might have frequent nosebleeds or intense itching.



Many liver conditions have the same symptoms as biliary atresia. To make sure he finds the right cause, your child's doctor may test her blood for high levels of bilirubin. He may also do some or all of the following:

  • X-rays: A small amount of radiation creates a picture that's recorded on film or a computer. This checks for an enlarged liver and spleen.
  • Ultrasound: High-frequency sound waves show detailed images of her organs.
  • Liver scans: Special X-rays use chemicals to create an image of her liver and bile ducts. This can show if and where the flow of bile is blocked.
  • Liver biopsy: Her doctor will take a small sample of tissue so it can be looked at under a microscope. This can show if it's likely she has biliary atresia and help rule out other liver problems such as hepatitis.
  • Diagnostic surgery: She'll be given medicine to make her sleep, and her doctor will make a small cut in her stomach area so he can look at her liver and bile ducts.


The most common treatment is the Kasai procedure. It's done if the blocked bile ducts are outside the baby's liver. During the operation, your baby's surgeon will replace the blocked bile ducts with part of her intestine. This lets bile drain from her liver through the new "duct" and into her intestine.

If it's done before your baby is 3 months old, the surgery has about an 80% success rate. If it's not successful, babies usually need a liver transplant within 1 to 2 years.

If the blocked bile ducts are inside the liver, medication may help get rid of bile, and vitamin A, D, and E supplements may be prescribed. But a liver transplant probably will be needed.


If a baby has a successful Kasai procedure, she may recover and have a full, active life. But in most cases, she'll need specialized medical care for the rest of her life. Eventually, she may also need a liver transplant.

WebMD Medical Reference Reviewed by Dan Brennan, MD on August 21, 2020



American Liver Foundation: "Biliary Atresia."

Children's Liver Disease Foundation: "Biliary Atresia."

National Institute of Diabetes and Digestive and Kidney Disorders: "Biliary Atresia."

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