What is biliary atresia?
Biliary atresia (pronounced BILL-ee-air-ee ah-TREE-zhuh) is a liver condition. It occurs when a baby's bile ducts do not form normally. Instead of being open tubes to drain bile from the liver, the bile ducts are missing or they are blocked because of scarring.
Bile is a liquid made by the baby's liver. It helps the body digest (break down) fats. Normally, bile flows through tiny bile ducts within the liver into larger ducts that lead to the gallbladder and intestine. The gallbladder stores bile until the body needs it to digest food. Food triggers the gallbladder to contract and squeeze bile out into the intestine.
In babies with biliary atresia, the abnormal or scarred bile ducts keep bile from flowing out of the liver. Instead, bile backs up in the liver. Backed-up bile (congestion) in the liver is called cholestasis. It causes scarring (cirrhosis) and jaundice, or a yellowish tint to the skin and eyes. This is because bile contains a yellow pigment, called bilirubin.
Biliary atresia in children
About 1 baby in 15,000 has biliary atresia. Doctors do not know why it occurs. In most cases, it is present early in infancy. Usually it's found in the first 1 to 2 months of life. If it's not found until after 2 months of age, it seems to progress to worse disease.
The bile ducts may be abnormal when the baby is born (congenital). In some babies, the bile ducts may not form correctly while the baby is developing. A small number of babies with biliary atresia (about 15%) may have other structures that did not form normally — their intestine, spleen and portal vein, which goes to the liver.
In some babies, the ducts form but cells that cause swelling (inflammation) may collect around the ducts. The inflammation may make the ducts swollen and narrower, closing them off and creating scars.
Surgery to remove blockage
In order to survive, babies with biliary atresia need surgery. This is usually done in the first 2 months after birth. The goal is to remove any blockage in the ducts outside the liver and create a way for bile to drain straight from their liver into their intestines. This surgery is called the Kasai procedure. It is named after Dr. Kasai of Sendai, Japan, who developed the surgery in the 1960s.
Without surgery, biliary atresia leads to liver failure. A baby with liver failure may be able to have a liver transplant. Biliary atresia is the most common reason for liver transplants in children. It accounts for nearly half of them.
If your baby's doctor suspects biliary atresia, the doctor will start with a thorough exam and will ask about your baby's health background. Then the doctor will ask for blood tests to tell how your baby's liver is working and to check bilirubin levels.
Your baby's doctor may also want to have pictures taken of the inside of your baby's body, such as an ultrasound and a hepatobiliary iminodiacetic acid (HIDA) scan. A HIDA scan allows doctors to see whether a special dye that collects in the liver can pass out of the liver through the bile ducts.
To learn more about your baby's liver and bile ducts, the doctor may order a biopsy . This could mean drawing some cells from your baby's liver with a syringe (needle biopsy) or doing surgery to remove a small sample of your baby's liver.
If these tests suggest bile flow is blocked, then surgery is done in most cases. During surgery, doctors can check how well the bile ducts developed and can diagnose atresia.
Treating Biliary Atresia
Babies with biliary atresia need surgery to remove any blockage in the bile ducts outside the liver and create a way for bile to drain straight from their liver into their intestines. The surgery is called a Kasai procedure (portoenterostomy).
During a Kasai procedure, the surgeon removes the scarred, abnormal bile ducts outside of the baby's liver. Then the surgeon creates an extension of the small intestine, called a roux-en-Y (pronounced ROO-enn-WHY), that can reach up to the liver. The surgeon connects this extension to the liver at the place where the bile ducts come out of the liver.
The Kasai procedure tends to be more successful the earlier it's done. Usually the goal is to complete the surgery in the first 2 months after birth. The surgery may also be helpful for older babies, if they don't already have advanced liver disease.
Some children will recover with good liver function and bile flow after a Kasai procedure. Some will do well for a while, even a few years, and then their liver damage will get worse and their liver will fail. Then they will need a liver transplant.
Preparing for your child’s surgery
You can read about what to expect when your child visits a clinic at Children's, has surgery here or needs to stay in the hospital. You can get practical details about topics like what to do and bring the day of surgery and who will be on your child's care team.