Type I: classic autoimmune hepatitis, anti-smooth-muscle and/or antinuclear antibodies (ANA). Type II: associated with anti-liver/kidney microsomal (anti-LKM) antibodies, which are directed against cytochrome P450 2D6 (seen primarily in southern Europe). Type III pts lack ANA and anti-LKM, have antibodies reactive with hepatocyte cytokeratins; clinically similar to type I. Criteria have been suggested by an international group for establishing a diagnosis of autoimmune hepatitis.
Classic autoimmune hepatitis (type I): 80% women, third to fifth decades. Abrupt onset (acute hepatitis) in a third. Insidious onset in two-thirds: progressive jaundice, anorexia, hepatomegaly, abdominal pain, epistaxis, fever, fatigue, amenorrhea. Leads to cirrhosis; >50% 5-year mortality if untreated.
Rash, arthralgias, keratoconjunctivitis sicca, thyroiditis, hemolytic anemia, nephritis.
Hypergammaglobulinemia, positive rheumatoid factor, smooth-muscle antibody (40-80%), ANA (20-50%), antimitochondrial antibody (10-20%), false-positive anti-HCV enzyme immunoassay but usually not HCV RNA, atypical p-ANCA. Type II: anti-LKM antibody.
| TREATMENT | ||
Autoimmune HepatitisA treatment response occurs in 80% of pts, but may not prevent progression to cirrhosis. Foundation is prednisone or prednisolone 20-60 mg/d PO tapered to 10-20 mg/d over several weeks; often azathioprine 50 mg/d PO is also administered to permit lower glucocorticoid doses and avoid associated side effects. Symptoms may improve rapidly, but biochemical improvement may take weeks or months and subsequent histologic improvement (to lesion of mild chronic hepatitis or normal biopsy) up to 6-24 months. Therapy should be continued for 12-18 months. Relapse occurs in at least 50% of cases. The majority of pts require maintenance therapy with low-dose glucocorticoids or azathioprine 2 (mg/kg)/d. Other immunosuppressive agents have been used for medically refractory cases. |