Hepatitis Delta Virus

Hepatitis delta virus also known as hepatitis “D” Virus requires the presence of HBV for Virion assembly but not for replication. Both co-infection and super-infection of HBV with HDV result in more severe complications compared to infection with HBV alone. In combination with HBV, hepatitis D virus has the highest mortality of all the hepatitis infections.Following exposure to HDV, there is a period of 3 to 7 weeks for having an anti HDV positive test. Even after ending the incubation period of HDV, still the diagnosis of HDV may be established, using PCR which is more sensitive and specific than both IgM and IgG anti HDV.Title of IgM-anti HDV correlates with the level of HDV replication, and titles of 1:1000 are indicative of ongoing infection.The detection of interahepatic HDV antigen has been proposed as the “gold standard”of diagnosis of hepatitis delta virus infection; particularly when anti HDV is negative in the beginning of disease or chronically diseased patients. Another pitfall in diagnosis of HDV infection; can be found in triple infections of HBV, HDV and HCV. The inhibitory effects of HCVon HBV replication might be another factor for the decreasing of HDV antibody and perhaps false-negative anti HDV test.