A. Liver function tests – Explanation
Smooth muscle antibodies are associated with autoimmune hepatitis. Presentation is usually
insidious and extrahepatic clinical features are common
Autoimmune hepatitis
Autoimmune hepatitis is condition of unknown aetiology which is most commonly seen in young
females. Recognised associations include other autoimmune disorders, hypergammaglobulinaemia
and HLA B8, DR3.
Three types of autoimmune hepatitis have been characterised according to the types of circulating
antibodies present
| Type I | Type II | Type III |
| Anti-nuclear antibodies (ANA) and/or anti-smooth muscle antibodies (SMA) Affects both adults and children |
Anti-liver/kidney microsomal type 1 antibodies (LKM1) Affects children only |
Soluble liver-kidney antigen
Affects adults inmiddle-age |
Features
- may present with signs of chronic liver disease
- acute hepatitis: fever, jaundice etc (only 25% present in this way)
- amenorrhoea (common)
- ANA/SMA/LKM1 antibodies, raised IgG levels
- liver biopsy: inflammation extending beyond limiting plate ‘piecemeal necrosis’, bridging necrosis
Management
- steroids, other immunosuppressants e.g. azathioprine
- liver transplantation
