POLYMERASE CHAIN-REACTION FOR THE DIAGNOSIS OF VIRAL HEPATITIS-B AND HEPATITIS-C

Polymerase chain reaction is a highly sensitive technique for the detection of hepatitis B virus-DNA and hepatitis C virus-RNA in serum, liver tissue, and peripheral mononuclear blood cells. In chronic hepatitis B, it is particularly useful for identification of infectious subjects who are hepatitis B surface antigen positive and anti-hepatitis B e antigen antibody-positive, and for follow up of hepatitis B virus infections in liver transplantation programmes. Polymerase chain reaction detection of hepatitis C virus-RNA in serum may be the only means of confirming acute hepatitis C infection and also of identifying viraemia in the chronic disease, particularly in anti-hepatitis C virus antibody-negative individuals. It can also be used for direct evaluation of mother to child hepatitis C virus transmission. As in hepatitis B, polymerase chain reaction can be used for monitoring reinfection with hepatitis C virus after liver transplant, and has proved invaluable in identification of different hepatitis C virus genotypes. The efficacy of antiviral treatment can also be monitored using polymerase chain reaction. Polymerase chain reaction has thus shown numerous advantages for disease detection and monitoring despite the limitations imposed, for example, by possible contamination problems, and semiquantitative evaluations.