Autoimmune hepatitis is a rare cause of chronic hepatitis (inflammation in the liver). It appears to occur due to a combination of genetic and environmental factors.
Types
There are two types of autoimmune hepatitis, with different age distributions and autoantibodies.
Type 1 typically affects women in their late forties or fifties. It presents around or after menopause with fatigue and features of liver disease on examination. It takes a less acute course than type 2.
Type 2 usually affects children or young people, more commonly girls. It presents with acute hepatitis with high transaminases and jaundice.
Investigations
Investigations will show high transaminases (ALT and AST) and minimal change in ALP levels (a “hepatitic” picture). Raised immunoglobulin G (IgG) levels are an important finding.
Autoantibodies in type 1 autoimmune hepatitis are:
- Anti-nuclear antibodies (ANA)
- Anti-smooth muscle antibodies (anti-actin)
- Anti-soluble liver antigen (anti-SLA/LP)
Autoantibodies in type 2 autoimmune hepatitis are:
- Anti-liver kidney microsomes-1 (anti-LKM1)
- Anti-liver cytosol antigen type 1 (anti-LC1)
Liver biopsy forms part of the diagnosis. Key histology findings are interface hepatitis and plasma cell infiltration.
Management
Treatment is with high-dose steroids (e.g., prednisolone). Other immunosuppressants are also used, particularly azathioprine. Immunosuppressant treatment is usually successful at inducing remission (controlling the disease).
Liver transplant may be required in end-stage liver disease. Autoimmune hepatitis can reoccur in the new liver.
Last updated May 2023