Autoimmune hepatitis in children: an overview of the disease focusing on current therapies.

Autoimmune hepatitis (AIH) is an immune-mediated necroinflammatory disease of the liver characterized by elevation of IgG, presence of characteristic autoantibodies, and histological features of interface hepatitis. Two types of juvenile AIH have been recognized according to seropositivity for smooth muscle and/or antinuclear antibody (AIH type 1) or liver kidney microsomal antibody (AIH type 2). The exact pathogenesis of AIH is still unclear, but it is known that unidentified environmental factors, and occasionally drugs, might trigger disease in genetically susceptible individuals. The clinical spectrum of this disease is very wide, ranging from asymptomatic individuals with abnormal liver function to those with fulminant liver failure. The diagnosis is based on a combination of biochemical and histological parameters and on exclusion of other liver diseases. It is a relatively rare but devastating disease, which progresses rapidly unless immunosuppressive treatment is started promptly. Standard therapy consists of a combination of corticosteroids and azathioprine, which is efficacious in 80% of patients. Alternative therapies are increasingly being explored in patients who do not respond to standard treatment and/or have intolerable side-effects. The purpose of this paper is to review our current knowledge about AIH in children, evaluating mainly the therapeutic options for its treatment, considering also the newer immunosuppressant agents used in difficult-to-treat cases.