Congenital liver defects are liver defects that are present at birth. They are rare. These liver disorders usually block the bile ducts. This affects the flow of bile. Bile is a fluid made in the liver. It helps with digestion. The bile ducts take bile from the liver and bring it to the gallbladder to be stored. A meal stimulates the gallbladder to release bile into the small intestine for digestion.

When the bile ducts are blocked, bile builds up in the liver. This damages the liver.

Some congenital liver defects include:

• Biliary atresia. A life-threatening condition in infants where the bile ducts are blocked or have developed abnormally. This blocks the flow of bile from the liver.
• Biliary (choledochal) cyst. A condition where the bile ducts, either inside or outside the liver, have abnormal dilations. This can also block the flow of bile.

Doctors don't know the exact cause of congenital liver defects. Congenital implies that the baby was born with the problem. The abnormality occurred while the fetus was still in developing in the womb. This might happen because of one or more of the following:

• A viral or bacterial infection
• An immune system problem, such as when the immune system attacks the liver or bile ducts for unknown reasons
• A genetic mutation. This is a long-lasting change in a gene's structure.
• A problem during liver and bile duct development in the unborn baby
• Contact with toxic substances

Congenital liver defects that affect the flow of bile share some common symptoms. Each child's symptoms may vary, but may include:

• Yellowing of the skin and eyes (jaundice)
• Dark-colored urine
• Pale, white, or gray-colored stools
• Belly (abdominal) mass
• Itching
• Abdominal (belly) pain
• Not gaining weight (failure to thrive)
• Malnutrition
• Baby appears sick, too fussy, or too sleepy

The symptoms of congenital liver defects may look like other health problems. Always talk with your child's doctor for a diagnosis.

In most cases, congenital liver defects that affect the flow of bile are diagnosed at birth or soon after. Your child's doctor will take a full health history and do a physical exam. Your child may also have tests. These include:

• Laboratory tests (blood, urine, and stool)
• Liver enzyme tests. Special blood tests to check if the liver is inflamed.
• Liver function tests. Special blood tests to see if the liver is working the way it should.
• Liver biopsy. Tissue samples from the liver are removed (with a needle or during surgery) and checked under a microscope.
• CT scan. An imaging test that uses both X-rays and computer technology to make horizontal images (called slices) of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than standard X-rays.
• Ultrasound. This imaging test uses high-frequency sound waves and a computer. It creates images of blood vessels, tissues, and organs. It is used to see internal abdominal organs, such as the liver, spleen, and kidneys. An ultrasound can check blood flow through different vessels.
• MRI. This imaging test uses a combination of large magnets, radio frequencies, and a computer. It makes detailed images of organs and structures in the body. MRCP (magnetic resonance cholangiopancreatography) is a special type of MRI that takes pictures of the bile duct and internal organs.
• HIDA (hepatobiliary) scan. A nuclear medicine test where a medicine is followed under X-ray out of the bile system.

Treatment will depend on the type of congenital liver defect your child has. Your child may need surgery.

If your child has a choledochal cyst, they must have surgery to remove the cyst and allow normal bile flow. The type of surgery will depend on where the cyst is located, as well as other factors.

Babies with biliary atresia are treated with a type of surgery called the Kasai procedure. This removes the damaged bile ducts and replaces them with a section of small intestine. Bile then flows right to the small intestine. A liver transplant may be needed.

If untreated, congenital liver defects can lead to liver damage and death. They can lead to infection, narrowing (stricture) of bile ducts, stones, long-term liver problems, and sometimes cancer.

Once surgery is done and the defect is repaired, children can often lead healthy lives. This will also depend on how much liver damage occurred before the surgery.

If your child had a liver transplant:

• They must take antirejection medicines (immunosuppressants). These medicines help stop the immune system from attacking the new liver. Your child will have to take these medicines for as long as they have the new liver.
• Your child will likely need to take vitamin supplements.

After treatment, your child should be checked regularly by their health care team.

Your child's doctor may suggest support groups. This can help you and your child adjust to their condition. This situation is very stressful on parents and siblings. Think about support groups for all family members or getting professional counseling. This can be helpful if the emotional, physical, and financial strain of caring for an ill child is causing great distress to any family member.

If your child has any symptoms of a congenital liver defect, call your child's doctor right away. Also call the doctor if your child develops symptoms after treatment.

If your child had a liver transplant, ask your child's health care team what rejection symptoms you should look for. Also ask them when to contact your child's doctor.

• Congenital liver defects are liver disorders that are present at birth. They are rare.
• In most cases, these disorders affect the bile ducts.
• When bile backs up in the liver, it damages the liver.
• Some type of surgery is often needed.
• If your child has biliary atresia, a liver transplant may be needed.

Tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours and on weekends and holidays. This is important if your child becomes ill and you have questions or need advice.