Hepatitis B surface antigen (HBsAg) is considered the best marker for the diagnosis of hepatitis B virus (HBV) infection. Mutations of the s gene involving amino acid substitutions within the a determinant could affect the sensitivity of diagnostic tests. In the present study, HBsAg mutants were detected in 3 immunocompromised patients, previously found to be HBsAg negative and anti-HBs positiv...

BACKGROUND The usual criteria for analysis of hepatitis B surface antigen (HBsAg) are detection of HBsAg and result confirmation by antibody neutralization. We observed that with the Immulite 2000 HBsAg assay [Diagnostics Product Corporation (DPC)] a relatively high percentage of weakly reactive (WR) samples did not pass the neutralization step. METHODS For each of 3 lots of Immulite 2000 HBs...

Occult hepatitis B virus (HBV) infection (OBI) is defined as low plasma level of HBV DNA with undetectable HBV surface antigen (HBsAg) outside the preseroconversion window period. The mechanisms leading to OBI remain largely unknown. The potential role of specific amino acid substitutions in the S protein from OBI in HBsAg production and excretion was examined in vitro. HBsAg was quantified in ...

BACKGROUND The roles of single-nucleotide polymorphisms (SNPs) at HLA-DP and IL28B loci on hepatitis B surface antigen (HBsAg) seroclearance in chronic hepatitis B (CHB) infection are unknown. METHODS We compared the HLA-DP (rs3077, rs9277378, rs3128917) and IL28B (rs12979860, rs8099917) polymorphisms of 203 CHB patients achieving spontaneous HBsAg seroclearance with 203 age- and sex-matched ...

BACKGROUND & AIMS Patients with chronic hepatitis B virus (HBV) infection have a high risk for developing hepatocellular carcinoma (HCC). Patients with lower levels of hepatitis B surface antigen (HBsAg) have higher chances of losing HBsAg than those with high levels. However, little is known about whether higher levels of HBsAg increase risk for HCC. METHODS We followed 2688 Taiwanese HBsAg-...

BACKGROUND/AIMS The notion that acute hepatitis A superimposed on chronic hepatitis B infection leads to a worse outcome than acute hepatitis A alone remains controversial. The aim of this study was to determine the influence of the presence of hepatitis B surface antigen (HBsAg) on the severity of acute hepatitis A. METHODS We retrospectively analyzed 449 patients hospitalized for acute hepa...

Various findings concerning the clinical significance of quantitative changes in hepatitis B surface antigen (HBsAg) during the acute and chronic phase of hepatitis B virus (HBV) infection have been reported. In addition to being a biomarker of HBV-replication activity, it has been reported that HBsAg could contribute to the immunopathogenesis of HBV persistent infection. Moreover, HBsAg could ...

Hepatitis B virus (HBV) infection continues to be a major health problem worldwide. The large-scale immunization programs for persons in high-risk groups, newborns, and adolescents have greatly reduced the incidence of new infection, but the ∼400 million HBV carriers with HBV surface antigen (HBsAg) in the blood remain a burden that will dwindle only within decades. Furthermore, an unknown dise...