[A case of autoimmune hepatitis].

Autoimmune hepatitis (AIH) is a disorder of unknown aetiology that occurs in children and adults of all ages with a female predominance. The spectrum of presentation is wide, ranging from no symptoms to acute liver failure. The diagnosis is based on high level or serum gammaglobulins, characteristic circulating autoantibodies and histologic abnormalities (necrosis and inflammation) in the absence of other causes. AIH is classified on the basis of the autoantibody pattern: type 1 (antinuclear and/or smooth muscle antibodies) is the classic form whereas type 2 (liver-kidney microsome 1 antibody) is much less common and occurs mainly in childhood. Mixed forms of AIH that share features with other putative autoimmune liver diseases, primary biliary cirrhosis and primary sclerosing cholangitis, have been described. Because of therapeutic issues, it is important to distinguish AIH from other forms of hepatitis and the use of diagnostic scoring systems may be helpful. Treatment basis of AIH have not changed for the last 30 years. Initial treatment consists of corticosteroids associated with azathioprine. Budesonide may be at least as effective as systemic corticosteroids and reduces the frequency of side effects in non-cirrhotic patients. Long-term treatment consists of azathioprine. This treatment is rapidly effective but usually only suspensive since relapse after treatment withdrawal is the rule (80 % of cases). The probability of relapse is lower in case of complete biochemical response defined by normalization of transaminases, gamma-globulins and IgG and in case of histological response defined by the lack of interface hepatitis. The frequency of side effects justifies an attempt of drug discontinuation provided that criteria of clinical, biochemical and histological remission are achieved after at least 2 years of treatment.