3 types, based on identification of serum autoantibodies
Clinical Issues
• Affects patients of all ages, predominantly women
• Chronic disease by definition but may present clinically as acute or fulminant hepatitis
Ongoing hepatic injury and scarring with development of cirrhosis and end-stage liver disease
• Many patients have concurrent autoimmune diseases affecting other organs
• Laboratory tests
Elevated transaminases
Serum autoantibodies
Polyclonal hypergammaglobulinemia
• 1st-line therapy is immunosuppression with corticosteroids in combination with azathioprine
Most patients improve dramatically with treatment
– 65% of patients achieve clinical, biochemical, and histologic remission within 3 years
• Liver transplantation indicated for patients with fulminant hepatitis or decompensated end-stage disease
Microscopic
• Untreated autoimmune hepatitis (AIH) usually presents chronic hepatitis with marked interface activity and lobular injury
• Plasma cells may be prominent but are not constant feature of AIH
• Treated disease may present with normal biopsy or mild chronic hepatitis without specific histologic features
• Severe AIH may mimic acute viral hepatitis
• Extent of inflammation and injury (“grade”) and scarring (“stage”) may be scored
Portal Infiltrates Typical portal inflammatory cell infiltrates in autoimmune hepatitis (AIH) contain large numbers of plasma cells. Periportal interface activity , or “piecemeal necrosis,” is also a characteristic feature.
Lobular Injury Diffuse lobular injury with inflammation , hepatocyte swelling , and necrosis is characteristic of AIH.
Prominent Plasma Cells Prominent lobular inflammatory cell infiltrates with large numbers of plasma cells and hepatocyte injury are seen in this case of AIH.
Bridging Necrosis Both single-cell necrosis and areas of confluent or “bridging” necrosis are seen in this case of AIH. Plasma cells are prominent.
TERMINOLOGY
Abbreviations
• Autoimmune hepatitis (AIH)
Synonyms
• Lupus/lupoid hepatitis
• Plasma cell hepatitis
Definitions
• Ongoing hepatitis presumed autoimmune in etiology
• 3 types, based on identification of serum autoantibodies
, or “piecemeal necrosis,” is also a characteristic feature.
, hepatocyte swelling 
, and necrosis is characteristic of AIH.
and hepatocyte injury are seen in this case of AIH.
and areas of confluent or “bridging” necrosis 
are seen in this case of AIH. Plasma cells 
are prominent.
