Table of Contents
What Is Alagille Syndrome?
Bile ducts are tiny tubes that transport bile — the secretion produced by liver cells. These ducts carry bile to the gallbladder for storage, and to the small intestine, where it emulsifies fats in our diet. Bile is also involved in removing toxins, cholesterol and wastes from our body, and aids in the digestion of fat-soluble vitamins as well. The decreased number of bile ducts in people with Alagille syndrome results in accumulation of bile in the liver, a condition known as cholestasis. This build-up of bile may lead to liver scarring and liver disease. In 30 to 50 percent of affected children, the scarring may cause liver cirrhosis.
Causes Of Alagille Syndrome
Alagille Syndrome is a genetic disorder, and is thus inherited. It is related to the Notch signaling pathway and the Jagged1 gene. Mutations or alterations in the genes or signaling pathways, respectively, result in the formation of distorted bile ducts. The scarred tissue that develops due to the build-up of bile in the liver prevents it from functioning adequately.
Who Is At Risk?
Alagille syndrome is a worldwide phenomenon, affecting both males and females of all ages, races and ethnicities. It occurs in about one out of every 30,000 babies.
Common Symptoms Of Alagille syndrome
Children suffering from Alagille syndrome may experience the following symptoms, which are a result of the underlying disorder:
This occurs due to inadequate and restricted flow of bile, which causes products of metabolic breakdown to accumulate in the body. It may become persistent later in life, accompanied with pale stools, itching, deposition of fats in the skin, and growth retardation. Symptoms usually improve between the ages of four to ten.
- Cardiovascular Abnormalities
Narrowing of the bloods vessels that carry blood from the heart to lungs may lead to heart murmurs. However, this rarely causes problems in cardiac function.
- Abnormalities in the Spine
The bones in the spinal column resemble the shape of "wings" of a butterfly when X-rayed, but no movement disabilities or nerve damage is present.
- Abnormalities in the Eye
More than 90 percent of children experience this symptom. A specialized eye exam helps detect an additional circular line on the eye surface of patients suffering from Alagille syndrome.
- Facial Abnormalities
These particular features make patients, especially children, easier to recognize. They include a prominent and broad forehead, deep-set eyes, small and pointed chin, and straight nose.
- Chronic Cholestasis
The accumulation of bile in the liver causes this condition. It can cause mild to severe liver damage, along with the reduced emulsification of fats and mal-absorption of fat-soluble vitamins. Other symptoms may include nosebleeds, bleeding gums, itching and high levels of cholesterol in blood or cholesterol depositions in the skin. In very severe cases, complications such as hepatomegaly (enlarged liver) and splenomegaly (enlarged spleen) may develop as well.