| [ Summary ] |
About 1O% of chronic hepatitis B surface antigen (HBsAg) carriers have complications of chronic hepatitis. Some of them then show symptoms of progressive liver cirrhosis or hepatocellular carcinoma (HCC). Most of HBsAg carriers in blood donors, or the general population, have mild liver disease. In this paper, we report on the natural history of HBsAg carriers in such groups. The annual clearance rate of HBsAg in chronic HBsAg carriers, whose liver damage was mild, was 0.3 to 0.8%. This phenomenon depends on the age of the HBsAg carriers and it is due to the decrease in number viruses in their serum or liver. The majority of HBsAg carriers, have mild liver disease activity, and also develop liver cirrhosis or HCC. About half of them died of HBV-related liver diseases. With HBsAg cleared patients, some had persistent hepatitis B viremia and also developed liver cirrhosis or HCC. Moreover, recent studies have reported posttransplantation hepatitis B virus (HBV) infections occurring in recipients of donors who were infected HBV. In conclusion, though incidence of liver disease was low we should be careful about adverse complications with chronic HBsAg carriers.F-,G-, and TT-type viruses have been proposed as causes of hepatitis of the non-A to E varities. However, there have been no reports that support the involvement of F-type virus in the development of non-A to E hepatitis, G- and TT-type viruses have been detected in healthy subjects. As a result, these viruses are not candidates for the pathogens of non-A to E hepatitis. However, various new findings on the hepatitis B virus (HBV) have been reported which may change our view of this virus. One such finding is the detection of HBV-DNA in the liver and serum of subjects who are negative for hepatitis B surface (HBs) antigens. The second finding is the development of hepatitis in patients who had received a liver transplant from a donor who was negative for HBS antigen and positive for hepatitis B core (HBc) antibodies. Attention has been paid to the involvement of HBV being negative for virus markers to non-A to E hepatitis, in the development of non-A to E hepatitis. We studied the prevalence of HBV-DNA in various types of liver disease, and found that HBV-DNA was present in the following diseases (positive cases/total number of cases) : acute hepatitis(6/17, 35%), chronic hepatitis (0/4, O%), fulminant hepatitis (3/4, 75%), Iiver cirrhosis(1/12, 8%). Many characteristics of HBV-DNA including its state in the organs, infectivity, pathogenicity, and carcinogenicity, have not been elucidated and further studies are necessary. |