What is Biliary Atresia?
Biliary atresia is a rare disease of the liver and bile ducts that occurs in infants. Jaundice (yellowing of the skin) and pale stools that start in the first 4-8 weeks of life are the main signs of the disease.
Cells in the liver produce liquid called bile. Bile helps to digest fat. It also carries waste products from the liver to the intestines for removal from the body.
The biliary system is a network of channels and ducts. When the biliary system is working the way it should, bile drains from the liver into the intestines.
When a baby has biliary atresia, bile flow from the liver to the gallbladder is blocked. This causes the bile to be trapped inside the liver, quickly causing damage and scarring of the liver cells (cirrhosis). This eventually leads to liver failure.
When a baby has biliary atresia, bile flow from the liver to the intestine is blocked. This causes the bile to be trapped inside the liver, and the baby becomes jaundiced. The trapped bile in babies can quickly cause liver damage and scarring (cirrhosis). This eventually leads to liver failure.
Early cirrhosis and liver failure can be prevented by early diagnosis and surgery. Surgery includes taking out the blocked bile ducts and connecting the liver to the intestine to increase bile flow.
What Causes Biliary Atresia?
The causes of biliary atresia are not completely understood. For some children, biliary atresia may occur because the bile ducts did not form properly during pregnancy. For other children with biliary atresia, the bile ducts may be damaged by the body's immune system because of a viral infection that happened after birth.
Who is at Risk for Biliary Atresia?
Biliary atresia is a rare disorder. It occurs in one in 15,000 babies. It Biliary atresia affects girls more than boys and doesn’t usually happen in the same family.
There does not appear to be any link to medications taken during pregnancy.
Do Children with Biliary Atresia Have Other Associated Abnormalities?
Babies with biliary atresia may be born with other problems in the:
- Spleen (polysplenia)
- Intestine (malrotation)
- Kidneys (cysts)
What Are the Symptoms of Biliary Atresia?
Babies with biliary atresia look healthy when they are born. Symptoms of the disease typically appear anytime in the first two months of life. Symptoms include:
- Jaundice − a yellow coloring of the skin and eyes due to a high level of bilirubin (bile pigment) in the bloodstream. Jaundice caused by an immature liver is common in newborns. It usually goes away within the first 1-2 weeks of life. If your baby is jaundiced beyond 2 weeks, have their doctor order a test called direct or conjugated bilirubin. If this test is high, the baby needs to be seen by a specialist right away.
- Dark urine – Some of the bilirubin that increases in the blood is filtered by the kidneys and removed in the urine.
- Acholic stools (white or clay-colored stools) – This happens because no bile or bilirubin is being emptied into the intestine. Bile gives stool its green or brown color. Without bile or bilirubin, stool is without color (often white or gray).
- Weight loss and irritability − develops when the level of jaundice increases.
How Is Biliary Atresia Diagnosed?
Jaundice may be present with other liver disorders. Several tests are needed to get the correct diagnosis.
- Blood tests are done to tell if there are liver function abnormalities. They may also identify the cause (etiology) of jaundice. Hepatologists at Cincinnati Children’s developed a simple blood test called MMP-7 that is used to identify babies with biliary atresia.
- An abdominal ultrasound can tell if there is a small gallbladder or none at all. The gallbladder is the organ that stores bile. If this organ is missing, that often indicates biliary atresia.
- A liver biopsy tells if an infant is likely to have biliary atresia. In a liver biopsy, a tiny sample of the liver is removed with a needle. That sample is looked at under a microscope. If the biopsy shows that the infant has biliary atresia, further surgery will confirm the diagnosis and treat the condition.
- Surgery and a special x-ray called operative cholangiogram are important to confirm and create a new passage for the bile.
How is Biliary Atresia Treated?
Biliary atresia cannot be treated with medication. A surgery called Kasai procedure (also known as a or hepatoportoenterostomy) creates a path of bile flow from the liver into the intestine.
The surgeon removes the damaged ducts outside of the liver (called extrahepatic ducts). They find smaller ducts that are still open and draining bile. The surgeon then attaches a loop of intestine to this portion of the liver. This allows bile to flow from the remaining healthy bile ducts into the intestine.
After this procedure, infants are usually in the hospital for seven to 10 days to heal. Long-term antibiotic therapy is given to reduce the risk of infection. Additional medications may be used to promote bile flow and help the surgery be successful.
With an experienced hepatologists and surgeons, the Kasai procedure is successful in 60 to 85 percent of the patients. This means that bile drains from the liver and the jaundice level goes down.
The Kasai procedure is not a cure for biliary atresia. It does allow babies to grow and have good health for several, sometimes for many years. About 25% of patients who undergo a Kasai procedure do not need a liver transplant.
Biliary atresia is the most common reason for liver transplantation in children in the U.S. Eighty-five percent of all children who have biliary atresia will need to have a liver transplant before they are 20 years old.
Survival after surgery has increased dramatically in recent years. Children with biliary atresia who have a liver transplant tend to do very well.
Success with the Kasai procedure is related to:
- Age. The younger an infant at the time of surgery, the more likely the surgery will be successful. By the time an infant is older than about 3 to 4 months old, surgery is unlikely to be helpful.
- Extent of cirrhosis (scarring and damage to liver tissue) at the time of surgery.
- Center experience – at Cincinnati Children’s, successful restoration of bile drainage has been achieved in 80% of the babies over the past five years.
Nutrition and Biliary Atresia
Children with liver disease have more metabolic needs than healthy children. This means that children with biliary atresia may need more calories.
A child with biliary atresia and jaundice cannot properly digest fats. This is because not enough bile gets to the intestine. Due to liver damage, there may also be a loss of vitamins and protein.
Guidelines from your doctor for your child's nutrition may include:
- Special formula and baby diet during the first year of life. For older children, a well-balanced diet, consisting of three meals a day plus small snacks in between meals.
- Vitamin supplements (specifically Vitamins A, D, E, and K as these are absorbed in fat, and children with biliary atresia cannot absorb these well).
- Adding medium-chain triglyceride (MCT) oil to foods and liquids or infant formulas. MCT adds extra calories that will help your child grow.
- High-calorie liquid feedings may be recommended if your child is too ill to eat normally. Feedings are given through a special tube (nasogastric tube) that is placed in the nose and guided down the esophagus and into the stomach.
Although digestion may return to normal after surgery, extra vitamins or MCT oil may be needed.
What Are the Complications of Biliary Atresia and What Can Be Done for Them?
Complications right after surgery are low. Most problems that develop are due to progression of the liver disease.
- After the Kasai procedure, it is common to get an infection in the bile ducts. This is treated with intravenous antibiotics. Treatment may continue with antibiotics taken by mouth.
- Jaundice or itching may occur. These can often be treated successfully with medications such as ursodeoxycholic acid.
- Many patients with cirrhosis have changes in blood flow through the liver and intestines. These changes may cause problems such as easy bruising of the skin, nosebleeds, retention of body fluid and enlarged veins (varices) in the stomach and esophagus.
Increased pressure in these veins can cause sudden and large amount of bleeding in the stomach and intestines. This can be a serious complication. With quick and experienced medical care, bleeding can usually be stopped. Sometimes treatment needs specialized procedures in which a hardening (sclerosing) agent is injected into the abnormal vessels.
- If retention of body fluid occurs, it can be treated with diuretics (medicine that helps remove excess water from the body).
As the disease gets worse, other complications of cirrhosis may also occur.
Liver Transplant for Biliary Artesia
If bile flow is not restored, liver transplantation will be necessary. A liver transplant operation removes the damaged liver and replaces it with a new liver from a donor.
Cincinnati Children’s has one of the largest and oldest pediatric liver transplant programs in the United States. The team offers an improved survival rate above the national average.. With a greater access to organs, the time children spend in the waiting list has decreased substantially at Cincinnati Children’s. Patients experience shorter average times on the transplant waitlist.
- The median wait time for a new liver at Cincinnati Children’s is 3.7 months, compared to the national median wait time of 8.7 months.
- 66.2% of our patients receive a transplant within one year of waitlisting, compared to 49.3% nationally.
After a transplant, ongoing lifelong care is required. Frequent contact with doctors and other members of the transplant team is also necessary.
What is the Long-Term Outlook After the Kasai?
It is very possible to have success and long-term survival after the Kasai procedure. Historically, nearly half of all infants who have had a Kasai procedure require liver transplantation before age 5. Hepatologists and surgeons at Cincinnati Children’s are developing protocols to improve long-term survival and decrease the need for liver transplantation. Older children may continue to have good bile drainage and no jaundice.
Some children may develop portal hypertension and have gastrointestinal bleeding, collection of fluid in the abdomen (ascites) and enlargement of the spleen (hypersplenism).