Hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) share common mode of transmission and both are able to induce a chronic infection. Dual HBV/HCV chronic coinfection is a fairly frequent occurrence, especially in high endemic areas and among individuals at high risk of parenterally transmitted infections. The intracellular interplay between HBV and HCV has not yet been sufficiently clarified, also due to the lack of a proper in vitro cellular model. Longitudinal evaluation of serum HBV DNA and HCV RNA amounts has revealed that complex virological profiles may be present in coinfected patients. Dual HBV/HCV infection has been associated to a severe course of the liver disease and to a high risk of developing hepatocellular carcinoma. Despite the clinical importance, solid evidence and clear guidelines for treatment of this special population are still lacking. This review summarizes the available data on the virological and clinical features as well as the therapeutic options of the dual HBV/HCV infection, and highlights the aspects that need to be better clarified.