What is autoimmune hepatitis (AIH)?
Autoimmune hepatitis is an uncommon cause of chronic hepatitis in the United States. It occurs when immune cells mistake the liver's normal cells for harmful invaders and attack them. The disease can become chronic which means that the inflammation is persistent. The chronic inflammation gradually damages the liver cells, which can result in serious problems. AIH is also known as Lupoid hepatitis.
What causes AIH?
The cause is not clear. It is believed to be an autoimmune disease. In people with autoimmune diseases the immune system attacks part or parts of the body as if it were foreign.
Liver inflammation, or hepatitis, may occur along with other autoimmune diseases. These include:
- Graves disease
- Inflammatory bowel disease
- Rheumatoid arthritis
- Sjögren syndrome
- Systemic lupus erythematosus
- Type 1 diabetes
- Ulcerative colitis
Autoimmune hepatitis may occur in family members of people with autoimmune diseases. There may be a genetic cause.
Who gets AIH?
It most common in middle age women but it can affect people at all ages.
What are the symptoms of AIH?
Most patients have no symptoms at all. The most common early symptoms include feeling more tired than usual, feeling generally unwell and also joint and muscle pains which are usually worse in the mornings. Jaundice (eyes become yellow) can develop when the liver inflammation becomes worse. This is due to a build-up of the chemical bilirubin which is made in the liver and spills into the blood in some liver conditions. Without treatment, in time the persistent inflammation causes liver damage and can lead to cirrhosis or scarring of the liver.
Other symptoms can include:
- Loss of appetite
- Nausea or vomiting
- Pale or clay-colored stools
- Dark urine
- Abdominal distention
- Absence of menstruation (amenorrhea) may also be a symptom.
How is AIH diagnosed?
- The diagnosis is often made when you have tests for an unrelated condition. When symptoms suggest that you have hepatitis, your doctor will normally arrange tests to confirm hepatitis and to find the cause of the hepatitis. Tests usually include:
- Blood tests called liver function tests. These measure the activity of enzymes (chemicals) and other substances made in the liver. This gives a general guide as to whether the liver is inflamed, and how well it is working. These tests can confirm that you have hepatitis but not usually the cause of the hepatitis. Other blood tests can measure various auto-antibodies which occur in various autoimmune diseases. For example, antinuclear antibodies (ANAs) or smooth muscle antibodies (SMAs). Some of these auto-antibodies are raised in autoimmune hepatitis and indicate that this may be the cause of the hepatitis.
- A biopsy of the liver is likely to be taken to look at under the microscope. This can show inflammation and the extent of any cirrhosis in the liver. The type of cells involved in the inflammation usually help to confirm the diagnosis of autoimmune hepatitis, and to rule out other causes of hepatitis.
Exams and Tests
Tests for autoimmune hepatitis include the following blood tests:
- Liver function tests
- Anti-liver kidney microsome type 1 antibody (anti LKM-1)
- Anti-nuclear antibody (ANA)
- Anti-smooth muscle antibody (SMA)
- Serum IgG
- Liver biopsy to look for long-term hepatitis
What is the treatment for AIH?
- Early treatment can improve symptoms, reduce the risk of complications, and also greatly improve your outlook. Steroid medication (usually prednisone) is the usual first treatment. Steroids are good at reducing inflammation. A high dose is usually needed at first. The dose is then gradually reduced over a few weeks. The aim is to find the lowest dose needed to control the inflammation. The dose needed varies from person to person. Azathioprine (Imuran) is an immunosuppressant medicine that works in a different way to steroids. It is usually used in addition to the steroid. A steroid plus azathioprine tends to work better than either alone. Also, the dose of steroid needed is usually less if you also take azathioprine. This means that any side-effects from steroids may be less severe.
- Treatment works well in most cases. Usually, the inflammation settles and symptoms improve within a few months of starting treatment. However, it may take a year or more to get the disease totally under control. Azathioprine is usually taken for at least three years.
- Some people may need a liver transplant
Complications may include:
- Side effects from steroids and other medicines
- Hepatocellular carcinoma
- Liver failure
When to Contact a Medical Professional
Call your health care provider if you notice symptoms of autoimmune hepatitis.
Autoimmune hepatitis cannot be prevented in most cases. Knowing the risk factors may help you detect and treat the disease early.