Update on occult hepatitis B virus infection

Core Tip

Core tip: Occult hepatitis B infection (OBI) is defined as negative hepatitis B surface antigen and positive/negative anti-hepatitis B core immunoglobulin G status but hepatitis B virus (HBV) DNA is detectable in serum and liver tissue. Genotypes A, C, G, E and D have been found among patients with OBI in different regions of the world. Genotype D is the only dominant genotype among Iranian OBI patients. OBI has been reported among many high risk groups, including blood donors, liver transplant recipients, patients co-infected with hepatitis C virus/human immunodeficiency virus, patients undergoing immunosuppressive therapy or hemodialysis, patients with liver cirrhosis, cryptogenic liver disease, or abnormal alanine transaminase, healthcare workers, patients with lymphoma or rheumatoid arthritis. It is recommended that to manage and reduce OBI and HBV carriage, the screening of HBV DNA be implemented among high risk groups by means of highly sensitive molecular assays periodically. In addition, comprehensive investigations are needed to understand the epidemiology of OBI worldwide.