SARS-CoV-2 and chronic hepatitis B: focusing on the possible consequences of co-infection

The pandemic of 2019 coronavirus disease (COVID-19) has become a world public health challenge. A new member of Coronaviridae family, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been identified as the causative of COVID-19. Although SARS-CoV-2 infection has a direct impact on the respiratory function, extra-respiratory complications such as liver damage have been reported in some cases. However, the exact mechanisms of liver injury in SARS-CoV-2 infection remain largely unexplored. It has also been suggested that patients with pre-existing liver disease are significantly influenced by COVID-19. Considering the double burden of chronic liver diseases and SARS-CoV-2 on health systems, investigating the interrelationship between COVID-19 and underlying liver disease and providing clear recommendations on treatment are very much needed. Viral hepatitis is recognized as one of the substantial risk factors for chronic liver diseases. Hepatitis B virus (HBV) is a main cause of liver failure, cirrhosis and hepatocellular carcinoma (HCC). Since both HBV and SARS-CoV-2 affect liver physiology, investigating the possible interactions and effects of SARS-CoV-2/HBV co-infection is increasingly important. This review highlighted the molecular and clinical consequences of SARS-CoV-2/HBV co-infection.