Clinical epidemiology of fulminant hepatitis in Japan before the substantial introduction of liver transplantation: an analysis of 1309 cases in a 15-year national survey

Background: The low incidence of fulminant hepatitis (FH) makes it difficult to accurately assess its viral etiology and clioical characteristics. Additionally, the therapeutic options for FH have markedly changed over the years because of the substantial introduction of living-donor liver transplantation. Aim: To analyze and summarize a large-scale national survey on FH in the pretransplantation era in Japan. Method: An analysis of answers to an annual questionnaire sent to 313 centers for liver diseases in Japan between 1983 and 1997. Results: During the study period, 1309 patients were registered as having fulminant hepatitis. The causes of FH were: hepatitis A virus (HAV) in 7.8%, hepatitis B virus (HBV) in 23.8%, probable HBV (positive for serum HBs antigen or HBV DNA and negative for the IgM anti-hepatitis B core antibody) in 13.8%, non-A, non-B hepatitis in 29.3%, drug-induced in 9.3, and unknown in 16.0% of these patients. The incidence of HBV-related cases did not decrease during the study period. The acute type had a significantly better prognosis than the subacute type (survival rate, 36.2% versus 15.3%, P < 0.001). The survival rate tended to improve in the third 5-year period for the acute type (28.6% [1983-1987] versus 43.3% [1994-1997]), but not for the subacute type (15.4% versus 12.3%). Conclusions: HBV remains a major cause of fulminant hepatitis in Japan. New therapeutic modalities, including liver transplantation, are required for improving the prognosis, in particular, for the subacute type of fulminant hepatitis. (C) 2004 Elsevier B.V. All rights reserved.