title: Quantitative detection of hepatitis B surface antigen by chemiluminescent microparticle immunoassay during lamivudine treatment of chronic hepatitis B virus carriers.
abstract: The usefulness of fully automated chemiluminescent microparticle immunoassay (Architect HBsAg QT) for monitoring serum levels of hepatitis B virus (HBV) during antiviral therapy remains unclear. Using this assay, hepatitis B surface antigen (HBsAg) was measured in 20 patients with chronic hepatitis B before and during lamivudine treatment. At the start of therapy, 12 patients had detectable hepatitis B e antigen (HBeAg) and 8 did not. The median serum HBV DNA level and HBsAg concentration (25th-75th centile) were 7.2 (6.1-7.8) log genome equivalents/ml and 3,932 (1,585-12,330) IU/ml, respectively. The HBsAg concentration was significantly higher in HBeAg positive than in HBeAg negative patients (P=0.031). There was a significant correlation between the HBsAg concentration and HBV DNA level (r=0.490, P=0.027). The HBsAg concentration negatively correlated with patient age (r=-0.395, P=0.085). After the start of lamivudine therapy, HBV DNA levels fell rapidly in all patients. Serum HBsAg concentrations also fell in most patients, but to a lesser extent. When drug-resistant variants emerged, serum HBsAg usually increased before biochemical breakthrough. Although HBV DNA was elevated persistently after the emergence of drug-resistant variants, the increase in HBsAg was transient. In some patients, the increase in HBsAg preceded the increase in HBV DNA. Monitoring of serum HBsAg concentrations with the use of Architect HBsAg QT, in addition to measurement of HBV DNA levels, is helpful for evaluating the response to lamivudine treatment and for the early detection of drug-resistant strains.
authors.affiliation: Department of Hepatology, Osaka City University Medical School, Abeno-ku, Osaka, Japan.
authors.forename: Madoka
authors.initials: M
authors.lastname: Kohmoto
authors.forename: Masaru
authors.initials: M
authors.lastname: Enomoto
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tamori
authors.forename: Daiki
authors.initials: D
authors.lastname: Habu
authors.forename: Tadashi
authors.initials: T
authors.lastname: Takeda
authors.forename: Norifumi
authors.initials: N
authors.lastname: Kawada
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: Shuichi
authors.initials: S
authors.lastname: Seki
authors.forename: Susumu
authors.initials: S
authors.lastname: Shiomi
authors.forename: Shuhei
authors.initials: S
authors.lastname: Nishiguchi
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D002353:Carrier State / Q000188:drug therapy; D004279:DNA, Viral / Q000097:blood; D005260:Female; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000187:drug effects / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D019259:Lamivudine / Q000627:therapeutic use*; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D019259:Lamivudine