title: The role of HBsAg quantification for monitoring natural history and treatment outcome.
abstract: Since its discovery by Blumberg in 1965, the hepatitis B virus antigen (HBsAg) is used as the fingerprint of hepatitis B infection. The HBsAg level is a reflection of the transcriptional activity of cccDNA. It is an important marker that not only indicates active hepatitis B infection but can also predict clinical and treatment outcomes. Assays for HBsAg quantification are fully automated and have high output. HBsAg titres are higher in HBe antigen (HBeAg)(+) than in HBeAg(-) patients and are negatively correlated with liver fibrosis in HBeAg(+) patients. In HBeAg(-) chronic hepatitis B, an HBsAg level <1000 IU/ml and an HBV DNA titre <2000 IU/ml accurately identify inactive carriers. During PEG-IFN treatment, HBsAg quantification is used to identify patients who will not benefit from therapy as early as week 12 on therapy, so that treatment may be stopped or switched- 'week 12 stopping rule'. With nucleos(t)ide analogues (NA), the role of HBsAg quantification must be clarified. Several studies show that baseline and on-treatment HBsAg levels might identify patients that can be treated with no subsequent risk of reactivation. In clinical practice, HBsAg quantification is a simple and reproducible tool that can be used in association with HBV DNA to classify patients during the natural history of HBV and to monitor therapy.
authors.affiliation: INSERM, U-773, CRB3, Université Paris-Diderot, Hôpital Beaujon, Clichy, France. michelle.martinot@.inserm.fr
authors.forename: Michelle
authors.initials: M
authors.lastname: Martinot-Peignoux
authors.forename: Martine
authors.initials: M
authors.lastname: Lapalus
authors.forename: Tarik
authors.initials: T
authors.lastname: Asselah
authors.forename: Patrick
authors.initials: P
authors.lastname: Marcellin
mesh_terms: D000998:Antiviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D004279:DNA, Viral / Q000097:blood; D018450:Disease Progression; D016903:Drug Monitoring / Q000379:methods*; D004359:Drug Therapy, Combination; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics / Q000276:immunology*; D019694:Hepatitis B, Chronic / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use; D008103:Liver Cirrhosis / Q000097:blood / Q000821:virology; D009705:Nucleosides / Q000627:therapeutic use; D009711:Nucleotides / Q000627:therapeutic use; D011092:Polyethylene Glycols / Q000627:therapeutic use; D011237:Predictive Value of Tests; D011994:Recombinant Proteins / Q000627:therapeutic use; D013997:Time Factors; D016896:Treatment Outcome; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D015415:Biomarkers; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D009705:Nucleosides; D009711:Nucleotides; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; C417083:peginterferon alfa-2b; C100416:peginterferon alfa-2a