AUTOIMMUNE HEPATITIS AND HEPATITIS-C VIRU S-INFECTION

From autoimmune hepatitis (AIH) classification which recognizes three types of AIH, we discuss the main relations between hepatitis C virus (HCV) infection and AIH. Type I AIH is associated with antinuclear and antismooth muscle antibodies, and with other autoimmune diseases. The re is no relation between type I AIH and HCV. Type 1 anti-liver kidney microsome and anti-liver cytosol 1 antibodies represent the hallmark of type II AIH. Among type II AIH, two subgroups emerged: type IIa AIH (10-40%) are true AIH (sensitive to steroids but worsens with interfe ron alpha), whereas type IIb AIH (60-90%) appear as a particular form of HCV hepatitis. Type IIb AIH have a modern activity, a low titer of autoantibodies, anti-GOR antibodies but never anti-liver cytosol 1, no sensitivity to steroids but are sensitive to interferon alpha. The ha llmark of type III are anti-cytosol antibodies, but these AIH have the same characteristics as type 1 AIH. The classification between true A IH (I, IIa, III) or ''pseudo-AIH'' due to HCV infection has major ther apeutic implications. Steroids or immunosuppressive treatments are eff ective in type I, IIa and III AIH but have no efficacy in type IIb AIH . Alpha interferon has an efficacy in type IIb AIH, but it has no effi cacy and may even worsen hepatitis in type I, IIa and III AIH.