Three different autoimmune liver diseases
Three different autoimmune liver diseases
The term “autoimmune liver diseases” comprises different disease patterns that differ with regard to the degree of severity and clinical course, but have one important step in common with regard to the development of the disease: The body’s own defence system erroneously attacks the liver. The most important autoimmune liver diseases are:
- Autoimmune hepatitis (AIH)
- Primary biliary cholangitis (PBC)
- Primary sclerosing cholangitis (PSC)
There are also combinations of these diseases that show symptoms of different disease patterns. The autoimmune reaction always causes inflammation of the liver. Years later, this can lead to liver cirrhosis – so so-called shrinking liver.
Autoimmune Hepatitis (AIH)
In autoimmune hepatitis (liver inflammation) the erroneous activity of the own immune system targets liver cells (hepatocytes). This does often not cause any symptoms for a long time and only manifests itself in elevated liver test results for example during a routine examination. In some cases, the clinical course is rapid with marked signs of inflammation such as joint pain or abdominal pain. Also jaundice of the conjunctival membranes over the sclerae may point to a severe course of the disease requiring immediate medical action.
Autoimmune hepatitis may start at any age. Women are affected more often than men. The disease is diagnosed by blood tests and a tissue sample of the liver (liver biopsy). When diagnosed early enough, autoimmune hepatitis can be treated very effectively with drugs suppressing the immune system. In almost all patients inflammation of the liver can be suppressed completely by medical therapy. In that case, a long life with a very good quality of life can regularly be expected by the patients despite this chronic disease.
Primary biliary cholangitis (PBC)
Primary biliary cholangitis is the most common autoimmune liver disease. In this disease, the erroneous activity of the immune system leads to inflammation of the small biliary ducts inside the liver. Mainly middle-aged women are affected. PBC is diagnosed with blood tests including the liver function tests and further blood results. In order to determine the stage of the disease and to secure the diagnosis, a liver tissue sample (biopsy) is may be required.
Usually, permanent treatment of this autoimmune liver disease with a special bile acid (ursodesoxycholic acid, abbrev. UDCA) is successful. The natural substance protects the bile duct cells against attacks of the immune system and allows a good quality of life despite chronic disease.
Primary sclerosing cholangitis (PSC)
In contrast to the other types of autoimmune liver disease, the incidence of PSC is higher in men than in women, especially in young and middle-aged men. Inflammation and scarring of the larger bile ducts, often in combination with inflammatory bowel disease, is a typical sign of PSC.
Primary sclerosing cholangitis may be hard to detect. There is no specific blood test to verify the disease, and even examination of liver tissue may sometimes not allow a reliable diagnosis of PSC. Hence, imaging of the bile ducts via magnetic resonance imaging or endoscopy is necessary, since this may show the disease-typical signs of narrow and widened parts of irregular bile ducts.
Therapy of this disease is still controversial. The protective bile acid (ursodesoxcholic acid, UDCA) improves blood results, but does not seem to have a significant impact on the clinical course of the disease. In an aggressive clinical course, also immunosuppressive drugs as are in autoimmune hepatitis may be administered. New substances are currently being evaluated. Bacterial infections of the damaged bile ducts have to be treated rigorously in this disease, since infections may accelerate the course of the disease. It is important to detect and to treat malignant tumors of the bile ducts, that may occur as a consequence of PSC, at an early stage. Should the liver function decrease significantly during the course of the disease, liver transplanation is the treatment of choice.
Since diagnosis, therapy and control of PSC require specialist medical knowledge, patients should be treated in specialist clinics.