Updates on the treatment and outcomes of dual chronic hepatitis C and B virus infection.

Dual hepatitis C virus (HCV)/hepatitis B virus (HBV) infection is found in HBV or HCV endemic areas, and in specific populations exhibiting a high risk of parenteral viral transmission. Clinical observations have revealed that HCV/HBV dually infected patients demonstrate a higher risk of liver disease progression compared with HBV or HCV monoinfected patients. The viral activity responsible for liver disease progression can be determined by examining the viral loads of HCV and HBV and by conducting liver biopsy examinations. Recent trials have confirmed that the combination therapy of peginterferon alpha-2a or 2b and ribavirin for dual hepatitis patients with HCV dominance appears to be as effective and safe as it is in patients with HCV monoinfections. Strikingly, approximately 60% of dually infected patients with inactive hepatitis B before treatment develop HBV reactivation after the clearance of the HCV. The clinical significance of this HBV reactivation and the strategy to prevent and treat this event should be determined. Furthermore, approximately 30% of dually infected patients lost hepatitis B surface antigen (HBsAg) within 5 years after the start of peginterferon-based therapy, and 40% of them harbored occult HBV infection. The underlying mechanisms of their accelerating HBsAg seroclearance and the development of occult HBV await further investigations. Moreover, the optimal treatment strategies for dually infected patients who are seropositive for the hepatitis B e antigen must be explored. Finally, the advent of new direct-acting antiviral-based anti-HCV therapy may change the optimal therapies for patients with dual hepatitis in the near future, which warrants further clinical trials.