title: Clinical implications of HBsAg quantification in patients with chronic hepatitis B.
abstract: Quantification of serum hepatitis B surface antigen (HBsAg) helps the management of patients with chronic hepatitis B virus (HBV) infection. Median HBsAg levels differ significantly during the natural history of HBV infection, progressively declining from immune tolerance to inactive phase. The combination of an HBsAg <1000 IU/mL and HBV DNA <2000 IU/mL at a single time point accurately identifies true inactive carriers. During antiviral treatment, HBsAg levels decline more rapidly in patients under peg-interferon (Peg-IFN) than in those under nucleos(t)ide analogues (NUC), and in responders to peg-IFN compared to non responders suggesting that a response-guided therapy in both HBeAg-positive and -negative patients treated with Peg-IFN could improve to cost-effectiveness of this therapeutic approach. Given the low rates of HBsAg clearance on NUC therapy, new studies to test whether Peg-IFN and NUC combination fosters HBsAg decline in long-term responders to NUC, are being explored.
authors.affiliation: Hepatology Unit, Ospedale San Giuseppe, Università degli Studi di Milano, Milano, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Viganò
authors.forename: Pietro
authors.initials: P
authors.lastname: Lampertico
mesh_terms: D004279:DNA, Viral / Q000097:blood; D006147:Guanine / Q000031:analogs & derivatives / Q000627:therapeutic use; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D019694:Hepatitis B, Chronic / Q000188:drug therapy / Q000276:immunology*; D006526:Hepatitis C; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage; D019259:Lamivudine / Q000627:therapeutic use; D009705:Nucleosides / Q000627:therapeutic use; D011092:Polyethylene Glycols / Q000008:administration & dosage; D011744:Pyrimidinones / Q000627:therapeutic use; D011994:Recombinant Proteins / Q000008:administration & dosage; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use; D000077712:Telbivudine; D013936:Thymidine / Q000031:analogs & derivatives
chemical_list: D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D009705:Nucleosides; D011744:Pyrimidinones; D011994:Recombinant Proteins; D018894:Reverse Transcriptase Inhibitors; D000077712:Telbivudine; D019259:Lamivudine; D011092:Polyethylene Glycols; C413685:entecavir; D006147:Guanine; C417083:peginterferon alfa-2b; D013936:Thymidine