Autoantibodies in the follow-up of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a rare, chronic, immune mediated liver disorder with unknown origin, associated with elevation of serum transaminases and IgG, positivity of certain autoantibodies and characteristic histopathological alterations in the liver. The clinical scenario is variable, the disease can be asymptomatic for a long time, noticed accidently by liver enzyme elevation or diagnosed only when liver cirrhosis has already developed. In rare cases acute hepatitis with liver failure is the starting event. In general, immunosuppressive treatment is required to diminish the progression of liver destruction and to prevent liver transplantation. The most important autoantibodies involved in AIH diagnostics - antinuclear antibodies, smooth muscle antibodies, anti-liver kidney microsomal type 1, anti-liver cytosolic antigen 1 or anti-soluble liver antigen - can be used for definition of AIH subtypes, too. These parameters are included in current AIH diagnostic guidelines. Since the fate of the patients depends very much on the proper choice and efficacy of the applied therapy prognostic and predictive markers of disease outcome can be essential in initiating therapy, while markers of disease activity and therapy response can support follow-up. Some biochemical parameters or histopathological data can be used for these purposes, but the potential role of AIH-specific autoantibodies in these is not entirely clear. In this current review the potential use of classical and emerging autoantibodies in diagnostics, prognostics, and follow-up of AIH patients will be discussed.