Autoimmune hepatitis

The disease progresses to cirrhosis if left untreated. Liver cirrhosis is an irreversible stage and is reached in about half of those affected within 15 years of the onset of the disease. On the way to cirrhosis, the organ continuously loses functional tissue due to increasing scarring until it finally fails. In the final stage of AIH, only a liver transplant can save the patient's life. The disease also increases the risk of liver cancer.

It is not clear why the immune system attacks the liver in some people. It is possible that there is a genetic predisposition. Trigger factors such as viral and bacterial infections, drugs or toxins, together with impaired immune tolerance, could cause AIH to break out.

In some patients, the disease initially causes no or hardly any symptoms. Nonspecific symptoms such as fatigue, loss of appetite, nausea and vomiting or a feeling of pressure in the right upper abdomen may occur. However, AIH can also manifest itself as acute hepatitis with an icteric course. Typical signs are yellowing of the skin and eyes (jaundice), light-coloured stools, dark urine and itching. If the liver no longer performs its tasks adequately, this also becomes noticeable with disturbances of the metabolism, blood clotting and hormone balance. In women, menstruation may stop as a result of hormonal changes (amenorrhoea).

Asymptomatic AIH is often an incidental finding. Routine examinations may reveal increased levels of aminotransferases (AST, ALT), prompting the doctor to further investigate. Other patients seek medical advice because they suddenly feel worse for no apparent reason. The diagnosis of AIH is complex and is best made by an experienced specialist. First, viral causes must be ruled out. Inflammation values, the level of antibodies of the type immunoglobulin G (IgG) in the blood as well as autoantibodies directed against liver cells provide indications of the disease. Based on the antibody spectrum, doctors distinguish between two types: AIH type 1 (formerly called lupoid hepatitis) is present in the majority of cases and occurs more frequently between the ages of 20 and 40. Patients usually respond well to drug therapy.

In about 10 per cent of cases, doctors diagnose AIH type 2. This type usually manifests itself in childhood or adolescence and its symptoms resemble acute hepatitis. The prognosis is worse. Four-fifths of patients develop cirrhosis during their lifetime. Some experts still distinguish a type 3, which resembles type 1.

AIH is not curable. However, medication can prevent that more and more liver tissue is destroyed. In remission, IgG and aminotransferases normalise. Immunosuppressants are the drugs of choice. They reduce the body's own immune system so that it can no longer attack the liver cells.