What is autoimmune hepatitis?
Viruses cause many types of hepatitis. Autoimmune hepatitis (AIH) is one exception. This type of liver disease occurs when your immune system attacks your liver cells. AIH is a chronic condition that can result in cirrhosis (scarring) of the liver. Ultimately, it can lead to liver failure.
AIH occurs when your immune system mistakes your liver cells for foreign aggressors and creates antibodies to attack them. Doctors don’t know precisely why this occurs. However, certain risk factors have been identified, including:
- a family history of AIH
- a history of bacterial or viral infections
- being female
- the use of certain medications, such as minocycline
Other autoimmune conditions can cause symptoms of liver disease and are also associated with the development of AIH. These diseases include:
There are two types of AIH based on serum tests:
- Type I is more common, tends to affect young women, and is associated with other autoimmune diseases. This is the most common form of AIH in the United States.
- Type II primarily affects girls between the ages of 2 and 14.
While AIH generally occurs in adolescence or early adulthood, it can develop at any age.
Symptoms of AIH range from mild to severe. In the early stages, you may have no symptoms, but in later stages, symptoms can appear suddenly. They may also slowly develop over time.
AIH symptoms include:
- enlarged liver (hepatomegaly)
- abnormal blood vessels on the skin (spider angiomas)
- abdominal distention (swelling)
- dark urine
- pale-colored stools
Additional symptoms may include:
- yellowing of the skin and eyes (jaundice)
- itching caused by a build-up of bile
- loss of appetite
- joint pain
- abdominal discomfort
AIH can be easily confused with other illnesses. Symptoms are very similar to those of viral hepatitis. To make a proper diagnosis, blood testing is required to:
- rule out viral hepatitis
- determine the type of AIH you have
- check your liver function
Blood tests are also used to measure the levels of specific antibodies in your blood. Antibodies associated with AIH include:
Blood tests can also measure the amount of immunoglobulin G (IgG) antibodies in your blood. IgG antibodies help the body fight infection and inflammation.
A liver biopsy may sometimes be necessary to diagnose AIH. It can reveal the type and severity of your liver damage and inflammation. The procedure involves removing a small piece of your liver tissue with a long needle and sending it to a laboratory for testing.
Treatment can slow down, stop, and sometimes reverse liver damage. Approximately 65 to 80 percent of people with AIH will go into remission. However, remission can take up to three years.
Immunosuppressant drugs can be used to stop the immune system’s attack. Such drugs include 6-mercaptopurine and azathioprine. Taking immunosuppressant drugs may compromise your body’s ability to fight other infections.
Corticosteroids, usually in the form of prednisone, can directly treat liver inflammation. They can also serve as immunosuppressants. You will likely need to take prednisone for a minimum of 18-24 months. Some people must continue taking the drug for life to prevent AIH from recurring.
Prednisone may cause serious side effects including:
A liver transplantcan treat AIH. However, the disease can sometimes recur even after a transplant. According to the National Institute of Diabetes and Digestive and Kidney Diseases, there is an 86 percent one-year survival rate for people who have a transplant. The five-year survival rate is about 72 percent.
Potential complications of untreated AIH include:
- liver failure
- scarring of the liver (cirrhosis)
- liver cancer
- increased blood pressure in the portal vein, which supplies blood to the liver
- enlarged veins in your stomach and esophagus (esophageal varices)
- fluid accumulation in the abdomen (ascites)