Natural course and treatment of dual hepatitis B virus and hepatitis C virus infections.

In areas where hepatitis B virus (HBV) infection is endemic such as Southeast Asia, the Far East and southern Europe, a substantial number of patients are infected with both hepatitis C and B. Moreover, patients who are dually infected with hepatitis C virus (HCV) and HBV have been reported to carry a significantly higher risk of developing fulminant hepatic failure, liver cirrhosis and hepatocellular carcinoma than those with HCV or HBV infection alone. Such dually infected patients need careful medical attention and effective treatment. Dually infected hepatitis patients can be classified into 2 groups according to the dominant viral activity: the first in which hepatitis C dominates over hepatitis B (hepatitis C/B) and the second in which hepatitis B dominates over hepatitis C (hepatitis B/C). Their natural histories may differ and require distinct treatments. For hepatitis C/B, conventional interferon (IFN) alone has not been shown to be effective in the clearance of HCV RNA. IFN in combination with ribavirin for 6 months has been used to treat hepatitis C/B patients in a few pilot studies and a sustained HCV clearance rate could be achieved to an extent comparable to that in simple hepatitis C. Nevertheless, the treatment outcomes in those infected with HCV genotype 1 remain unsatisfactory. Systematic trials of treatment for hepatitis B/C patients have not yet been reported. In this article, we review recent updates in the natural history and treatment of dual HBV and HCV infections, and draw attention to several unresolved issues requiring further study. These efforts may culminate in better treatment for patients co-infected with HCV and HBV.