Update on occult hepatitis B virus infection

Abstract

The event of mutations in the surface antigen gene of hepatitis B virus (HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core (anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection (OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction (PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for: (1) patients with a previous history of chronic or acute HBV infection; (2) patients co-infected with hepatitis C virus/human immunodeficiency virus; (3) patients undergoing chemotherapy or anti-CD20 therapy; (4) recipients of organ transplant; (5) blood donors; (6) organ transplant donors; (7) thalassemia and hemophilia patients; (8) health care workers; (9) patients with liver related disease (cryptogenic); (10) hemodialysis patients; (11) patients undergoing lamivudine or interferon therapy; and (12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.

Hepatitis B Virus DNA in Sera of Apparently Healthy Carriers Blood Donors with Anti-Hbc Total Positive

“…Moreover, in 20% of the cases there is no evidence of any HBV serological marker (Raimondo, et al, 2008). This type of infection represents a potential transmission source of HBV via blood transfusion or organ transplantation (Makvandi, 2016).…”

Occult Hepatitis B Virus Infection With Increased Virus DNA Levels in a Chronic Hemodialysis Patient

“…Although OBI in chronic HD patients exhibited low HBV DNA levels, they could increase over 2.1 log copies/mL (20 IU/mL). HD patients are recommended to undergo HBV DNA screening for infection control (4). Limiting the patients exhibiting an isolated anti-HBc pattern may be considered reasonable.…”

Modeling the dynamics of hepatitis B infection, immunity, and drug therapy

“…They experience either a HBeAg‐negative chronic HBV infection (inactive carrier) phase with limited virus replication and normal ALT levels, or HBeAg‐negative CHB phase with high virus replication, high ALT levels, and liver inflammation. A last stage of infection, HBsAg‐negative stage (occult HBV) is characterized by loss of surface antigen, presence (or absence) of antibodies to the core antigen and detectable HBV DNA in serum and liver tissue …”

“…A last stage of infection, HBsAgnegative stage (occult HBV) is characterized by loss of surface antigen, presence (or absence) of antibodies to the core antigen and detectable HBV DNA in serum and liver tissue. 73 Loss of serum HBeAg in CHB patients is a desirable goal, as it often represents a partial immune control. 58 Two mechanisms of serum HBeAg removal have been proposed: seroconversion, 74,75 and mutations in the core promoter or precore region of HBV genome.…”