Pediatric Alagille syndrome (ALGS)

What is pediatric Alagille syndrome (ALGS)?

Alagille syndrome is a genetic disorder that usually affects the development and function of the liver. Specifically, it makes it hard for the liver to pass bile — a substance made by the liver that helps the body digest food and process waste — to the small intestine. This is because the liver has smaller or fewer bile ducts (tubes) than normal.

This can affect the body in lots of different ways. For example, the skin may become yellow or itchy, the liver may become enlarged and lose function, and the body may not absorb fats and vitamins as well.

Alagille syndrome can affect other organs too. This includes the heart, where issues can range from a harmless heart murmur to structural defects that require surgery.

Because the variety of potential symptoms and health impacts is so wide, children with Alagille syndrome should receive care from a multidisciplinary team, who can care for their full range of needs.

Alagile syndrome is named after Daniel Alagille (a French pediatrician) who described the disease with his colleagues in 1969.

What are the signs and symptoms of pediatric Alagille syndrome (ALGS)?

On the skin:

• Jaundice

• Excessive itching (pruritus)

• Yellow bumps (xanthomas)

In other organs:

• Liver disease

• Opaque ring in the cornea of the eye (posterior embryotoxon)

• Kidney disease

• Heart murmur (an unusual or extra heart sound)

• Problems with heart valves or the heart wall

• Blood vessel problems in the brain

Facial features:

• Deep-set eyes

• Large ears

• Small, pointed chin

• Wide forehead

Other:

• Vertebrae shaped like flying butterflies

• White or gray-colored stools

• Dark urine

• Poor weight gain or growth

How is pediatric Alagille syndrome (ALGS) diagnosed?

Many children with Alagille syndrome show jaundice and other signs of liver disease in the early months after being born. When that happens, we do tests right away to see what’s causing it. In other cases, children may have milder symptoms that show up when they’re a few years old. These can vary a lot, and none of them automatically mean a child has Alagille syndrome. So our experts look for combinations of common symptoms, such as jaundice, butterfly vertebrae, and certain features of the eye and face.

We use blood, liver biopsy and genetic tests to get a clear picture of what’s happening in the body and what’s causing it. Blood tests can measure vitamins and other contents of the blood that are often affected by Alagille syndrome. A liver biopsy means we study a small sample of liver tissue, which can have certain characteristics that indicate Alagille’s syndrome. A biopsy also helps us determine how advanced a child’s liver disease is. Finally, a genetic test will confirm the diagnosis in most cases.

If we know or suspect your child has Alagille syndrome, we do additional tests to check on their liver, kidneys, heart and other organs that are often affected by the disease. Sometimes Alagille syndrome doesn’t do any harm to other organs, but sometimes it can have a serious effect. Our care team includes experts in all these parts of the body who know what to look for and what treatments may be necessary.

What causes pediatric Alagille syndrome (ALGS)?

Most cases of Alagille syndrome happen because of a change in a specific gene. Sometimes this gene change is inherited from a parent, and sometimes it develops on its own while the fetus is developing. A small number of cases are caused by a change in a different gene, but the range of symptoms and effects on the body are the same.

How is pediatric Alagille syndrome (ALGS) treated?

We treat Alagille syndrome by bringing together all of the different specialists your child needs, including:

• Hepatologists (liver experts) who can prescribe medicines and perform procedures to improve the liver function and help with itching and managing complications

• Liver surgeons can perform surgeries to improve bile flow to relieve itchy or bumpy skin when medical therapy is not sufficient

• Heart and kidney experts who manage any treatments necessary to protect or improve the function of those organs

• Neurology experts who can manage structural abnormalities in the blood vessels of the brain

• Dietitians who can provide nutrition advice, including vitamin supplements and meal planning

All of these experts work together as one team, coordinating treatments and addressing all your child’s health needs.