Current trends in the diagnosis and treatment of autoimmune hepatitis in Japan.

While a certain international consensus has been reached regarding the diagnosis and treatment of autoimmune hepatitis (AIH), there are some unique clinical characteristics of AIH in Japan. For diagnosis of AIH using the new simplified criteria proposed by the International Autoimmune Hepatitis Group, it is necessary to re-evaluate the antibody titer determined by using HEp-2 cells, which are widely used in Japan, and the finding of emperipolesis in liver histology, although the criteria are useful for rapid identification of AIH in routine clinical practice. The use of azathioprine as first-line therapy for AIH is limited in Japan because the drug is not covered by the Japanese national health insurance. Concomitant use of ursodeoxycholic acid (UDCA) to reduce corticosteroids and use of UDCA as monotherapy are therefore considered promising. Moreover, a relatively good survival rate has been reported in patients who developed AIH-induced acute liver failure and underwent living-donor liver transplantation. Current trends in the diagnosis and treatment of AIH in Japan are described in this report with a review of recent findings.