[Viral replication, histologic damage and enzymatic activity in chronic hepatopathies caused by B virus]

Abstract

The future of patients with chronic hepatitis (HC) due to B virus depends above all on the tendency of the interaction between viral activity and immune response. Viral activity (replication) (RV) can be expressed in these patients by two variants: a) "complete" or "early", associated with the presence in serum of HBsAg, HBeAg, and significant DNA polymerase activity, and b) "incomplete" or "late", in which anti-HBe is found in serum and there are scant or no histopathologic changes ("healthy carriers" in some cases). In prolonged infections viral replication declines gradually, although viral capsid protein continues to be synthesized and DNA-HBV is integrated into the genome. Viral replication per se does not condition the histologic damage (DH) expressive of liver cirrhosis with HBV (HCB). Other publications take a different view of this problem. The increase in viral replication often is proportional to a rise in serum GPT (an expression of histologic damage), but viral replication is not always associated with a progressive disease course. The immune defense leads to cytolysis and subsequent elimination of the HB virus. Some patients with high HBsAg levels have little active forms of liver cirrhosis; the DNA-HBV integrated would be capable of producing HBsAg but not HBcAg. It is precisely this that induces the response of cytotoxic T lymphocytes at the level of the hepatocyte surface. The presence in serum of anti-HBe IgM would be related to the expression of HBcAg on the hepatocyte membrane and/or the liberation of HBcAg particles by lysed hepatocytes. The relationship between the degree of histologic damage and serum aminotransferase levels is better established.