HEPATITIS-C VIRUS-INFECTION AND LIVER-DISEASE - PECULIAR EPIDEMIOLOGIC AND CLINICOPATHOLOGICAL FEATURES

Hepatitis C virus (HCV) infection is associated with a wide spectrum o f liver disease ranging from asymptomatic carriage to severe forms of chronic hepatitis. HCV is not invariably pathogenic and generic hetero geneity of HCV could be a major cause of such a variability. In clinic al practice this means that presence and replication of the virus do n ot invariably imply a virus-induced liver damage. IOM antibodies that are the best diagnostic tools for the other forms of viral hepatitis a re not sensitive and specific enough for hepatitis C, therefore we hav e to look for alternatives. Detection of anti-HCV does not help to dis tinguish past from present infections and only anti-HCV seroconversion in previously negative patients can indicate a recent HCV infection. However, the Significant association between serum anti-C100-3 and HCV -RNA suggests that anti-HCV can be considered an indirect marker of HC V infectivity. In anti-HCV-negative infections and early acute hepatit is cases HCV-RNA detection will represent a valid diagnostic alternati ve. In patients undergoing antiviral therapy monitoring anti-HCV by im munoblotting assays and HCV-RNA by quantitative assays represent a val id tool to predict response that invariably has occurred in patients w ho had undetectable serum HCV-RNA and/or decreasing anti-HCV titres. A ssays that detect multiple anti-HCV antibodies all together appear uns uitable for monitoring because they miss the disappearance of single a ntibodies. Anti-C22 appears the most frequent and earliest to be detec ted and usually it has the highest titre. Anti-C100 titres decrease ea rlier than anti-C33 and anti-C22 in patients with chronic HCV hepatiti s who respond to antiviral therapy. The natural course of HCV infectio n appears to be characterized by three consecutive phases: disease, as ymptomatic carrier and recovery. If transition from the first to the l ast occurs very slowly or the disease phase persists for years it may warrant in susceptible hosts severe forms of liver disease.