AUTOIMMUNE LIVER DISEASE
What is autoimmune liver disease?
The most common autoimmune liver disease are autoimmune hepatitis and primary biliary cholangitis.
What is autoimmune hepatitis (AIH)?
This is a condition where the body’s own immune system attacks the liver causing damage. We do not know why this happens, but as it is a misdirected immune response, it is likely that AIH results from the immune system mistaking surface molecules on liver cells as “foreign” and therefore attacking these cells. The condition is usually lifelong (chronic).
Who is at risk?
Although AIH can affect anyone, it is more common in women, most often diagnosed around the age of 40-50 years. Up to half of those with AIH have another autoimmune condition such as thyroid disease, Type 1 diabetes, rheumatoid arthritis or inflammatory bowel disease.
What are the symptoms of AIH?
Symptoms can vary depending on the degree of liver inflammation phase of the illness. Some individuals at the beginning of the illness can have abdominal pain, fever, joint and muscle pains, nausea, rash, itching and weakness. More commonly, in the longer term, affected individuals have little in the way of specific symptoms, but may complain of tiredness. In those with severe liver damage, symptoms can include yellow discolouration of the skin (jaundice), fluid build-up in the abdomen and legs and confusion.
How is it diagnosed?
Most commonly the diagnosis of AIH is suspected in an individual found to have abnormal liver blood tests. The diagnosis is made based on several criteria including specific “blood tests and often a liver biopsy is needed. Assessment may also include imaging tests and a fibroscan to assess the level of liver scarring.
Does AIH progress?
Yes, if untreated the ongoing inflammation in the liver caused by the autoimmune attack can result in significant liver damage/scarring. Extensive liver scarring (cirrhosis) can result from this with significant health consequences including risk of liver failure.
What treatment is there?
Patients diagnosed with AIH usually need treatment in the form of medication that suppresses the immune system. At initial diagnosis this would usually include steroid tablets, but in the longer term other medication is used to keep the immune system in check. This condition needs to be assessed and managed by specialists with regular review.
Primary Biliary Cholangitis
What is primary biliary cholangitis (PBC)?
PBC (previously known as primary biliary cirrhosis) is a long-term condition affecting the bile duct cells within the liver. It is another autoimmune disease, where there is an inappropriate attack by the body’s own immune system on these cells. The result is accumulation of bile salts in the liver which causes damage and symptoms.
Who is at risk?
Approximately 90% of those diagnosed with PBC are women. It is not clear why this is, but the disease is most often diagnosed in late middle age and is more likely if there is a family history of PBC.
What are the symptoms of PBC?
The commonest symptoms are tiredness (fatigue) and itching (pruritus). Many people have no symptoms at all, but PBC can also be associated with dry eyes, joint pains and nausea. In advanced disease, jaundice can occur, as well as other symptoms of severe liver disease such as fluid build-up in the abdomen and legs, and confusion
How is PBC diagnosed?
Usually the diagnosis is made after a person is found to have abnormal liver blood tests, which prompts health profession to check the antibody test associated with PBC – “AMA”. The presence of this antibody in the context of abnormal liver tests is usually enough to diagnose the condition. In order to assess the severity of liver damage imaging tests are usually performed, as well as measurements of liver stiffness (transient elastography). Sometime a liver biopsy is performed.
Does PBC progress?
Yes, if untreated, PBC can progress, causing significant liver scarring through long term inflammation. However, if diagnosed and treated early, there is evidence that this progression can be prevented.
Is there treatment for PBC?
Yes, once diagnosis is established, all patients should be started on treatment. At present a drug called ursodeoxycholic acid (UDCA) is first line treatment, and is believed to work by displacing the toxic bile salts, therefore reducing damage. This treatment has been shown to slow disease progression in some people. There are also newer medications that may help those that do not respond to UDCA. Other treatments targeted at alleviating itch are also needed. The management of PBC requires specialist assessment and ongoing review.