Autoimmune hepatitis is usually a chronic form of hepatitis that frequently leads to progressive damage of the liver. However, in about 10-20% of cases, it may present like acute hepatitis. For reasons that are not fully understood, the body's immune system targets and attacks the liver. It is more common in women than men; in fact, according to the American Liver Foundation, 70% of those affected are female, usually between the ages of 15 and 40.
There are two forms of autoimmune hepatitis. The more common form is type I, which most often affects young women and may be found in association with other autoimmune disorders, such as type 1 diabetes, ulcerative colitis, and Sjogren syndrome. Type II is much less common and has been found to affect mostly girls between the ages of 2 and 14; it is more common in Europe than in the U.S.
Signs and Symptoms of autoimmune hepatitis correspond to those of hepatitis in general. See the section on Signs and Symptoms for detailed information.
Several tests for various autoantibodies may be ordered to help diagnose autoimmune hepatitis and to look for other associated autoimmune disorders. The most common of these include:
- Antinuclear antibodies (ANA)
- Smooth muscle antibodies (SMA)
- Antibodies to liver and kidney microsomes (anti-LKM1)
Typically, people who have type I autoimmune hepatitis have ANA, SMA, or both, and people who have type II have anti-LKM1.
Treatment for autoimmune hepatitis usually involves drugs that suppress the immune system, such as prednisone and azathioprine (Imuran), although these treatments may not be effective in all cases. Typically, autoimmune hepatitis can be controlled with these medications but cannot be cured. People with this disease must often take these medications for life. According to the National Digestive Diseases Information Clearinghouse, about 7 out of 10 affected people who are treated with the immunosuppressant drugs go into remission within 3 years of beginning treatment. Remission is when signs and symptoms disappear or are greatly decreased. If medication is stopped, the disease may return in some people. These medications do have some side affects associated with their use. People with mild forms of this disease may not be treated with these drugs.