Autoimmune Hepatitis

What is autoimmune hepatitis?

Autoimmune hepatitis (AIH) is a rare, usually lifelong liver disease in which your immune system mistakenly attacks your own healthy liver cells, causing inflammation. It isn't caused by alcohol and you can't catch it or pass it on to anyone else.

What are the symptoms of autoimmune hepatitis?

Many people with AIH, especially once it's well controlled, have no symptoms at all, and the condition is sometimes only picked up when a blood test done for another reason shows a problem with the liver. When symptoms do appear, the first thing people often notice is fatigue. Other possible symptoms include:

• yellowing of the skin and the whites of the eyes (jaundice), which may be less noticeable if you have brown or black skin
• itchy skin, or skin rashes
• feeling generally unwell
• joint pain
• pain in your abdomen, often under the right side of your ribs, over the liver
• nausea, vomiting or loss of appetite
• dark urine and pale stools
• diarrhoea.

Symptoms can develop gradually or quite quickly and can range from mild to more severe.

What causes autoimmune hepatitis, and who's at risk?

It isn't entirely clear what causes AIH, and there's currently no known way to prevent it. It's thought to result from a combination of a genetic predisposition and an environmental trigger, such as a viral infection, that causes the immune system to mistakenly attack the liver. Possible triggers include certain viral infections (such as Epstein-Barr virus, herpes, parvovirus B19, or hepatitis A, B or C) and, occasionally, certain medicines, including nitrofurantoin, minocycline and atorvastatin.

AIH is far more common in women than men, affecting somewhere between roughly 7 and 8 in 10 people with the condition, and most often appears between the ages of 15 and 40, though it can develop at any age. Around 1 in 3 to 1 in 2 people with AIH also have, or go on to develop, another autoimmune condition, such as thyroid disease, rheumatoid arthritis, ulcerative colitis, coeliac disease, type 1 diabetes, vitiligo, Sjögren's syndrome or Graves' disease. Some people with AIH have family members with the condition, suggesting an inherited susceptibility, though the specific trigger involved usually isn't known. Around 1 in 3 people already have cirrhosis (scarring of the liver) by the time they're diagnosed.

Are there different types of autoimmune hepatitis?

AIH is generally divided into 2 types, based on the antibodies your immune system produces:

• type 1 (classic AIH) is the most common form and can affect anyone, though it most often develops in women aged 40 and under
• type 2 is much less common, tends to be more severe, and typically develops in childhood.

Treatment approaches are broadly similar for both types.

How is autoimmune hepatitis diagnosed?

There's no single test for AIH, so doctors use a combination of your medical history, a physical examination, and several types of test to reach a diagnosis. Your doctor will ask about your symptoms, your alcohol intake, and any medicines or supplements you take, and will examine you for signs such as jaundice, an enlarged liver or spleen, or swelling in your abdomen, legs or ankles. Tests usually include:

• blood tests to check your liver enzyme levels (ALT and AST, which are typically raised in AIH) and to rule out other causes of liver disease, such as viral hepatitis or other liver conditions
• antibody tests, to look for the specific antibodies associated with AIH, along with a related protein called immunoglobulin G (IgG)
• imaging tests, such as an ultrasound, CT or MRI scan
• a liver biopsy, often needed to confirm the diagnosis and assess how much liver damage has occurred.

How is autoimmune hepatitis treated?

There's no cure for AIH, but it can usually be managed very effectively with medicines that calm down the immune system and reduce inflammation in the liver. Treatment typically starts with a high dose of a steroid, either prednisolone or budesonide (budesonide isn't suitable if you already have cirrhosis). Once the inflammation is under control, a longer-term immunosuppressant medicine, usually azathioprine or mycophenolate, is introduced, and the steroid dose is gradually reduced based on your liver blood test results.

The goal of treatment is remission, meaning all signs and symptoms of the disease disappear; this can take anywhere from several months to a few years to achieve. Once you've been in remission for at least 2 years, your doctor may consider stopping your immunosuppressant, though the disease can return afterwards: around half of people who reach remission will relapse at some point and need to restart treatment. If medicines don't fully control the disease, or if it progresses to liver failure or liver cancer, a liver transplant may be needed.

If you take corticosteroids for AIH, your doctor may also recommend calcium and vitamin D supplements to help protect your bones, since long-term steroid use can increase the risk of osteoporosis. Eating a healthy, balanced diet is otherwise recommended. If you develop cirrhosis, you'll usually have a liver ultrasound scan every 6 months, since cirrhosis increases the risk of liver cancer and regular scans help catch this early, when it's more treatable.

The outlook with treatment is good: around 91 in 100 people with AIH who receive treatment are still alive after 10 years, and around 70 in 100 after 20 years. Left untreated, the disease can progress seriously; around half of people with untreated AIH die within 5 years, underlining how much of a difference early diagnosis and treatment can make.

When should you see a doctor?

See your GP promptly if you notice unexplained tiredness, yellowing of your skin or eyes, itching, or the other symptoms described above, particularly if you already have another autoimmune condition. If you're already diagnosed and under specialist care, contact your hepatology team if your symptoms return, you develop new symptoms, or you're concerned about side effects from your medicines.

Seek urgent medical attention for signs that your liver disease may be getting significantly worse, such as new or worsening jaundice, confusion, or swelling of your abdomen or legs, as these can point to serious complications that need prompt assessment.