title: Comparison between Elecsys HBsAg II and architect HBsAg QT assays for quantification of hepatitis B surface antigen among patients coinfected with HIV and hepatitis B virus.
abstract: Hepatitis B surface antigen (HBsAg) quantification has been steadily gaining interest as a clinical marker of therapeutic efficacy, for which two commercial assays are currently available: Architect HBsAg QT (Architect) and Elecsys HBsAg II (Elecsys). HBsAg quantification was evaluated using both assays in 126 human immunodeficiency virus (HIV) and hepatitis B virus (HBV)-coinfected patients initiating treatment with tenofovir dipivoxil fumarate. Linear regression and correlation were used to establish the relationship between the two methods. Bland-Altman analysis was performed to determine mean between-assay difference and limits of agreement (LOA) (±2 standard deviations [SD]) both overall and stratified on HBV (hepatitis B envelope antigen [HBeAg] status, replication, genotype, HBV mutants) or HIV (CD4(+) cell count) cofactors. There was a significant correlation between Elecsys and Architect assays (correlation coefficient, r = 0.959; P < 0.001). HBsAg quantification using the Elecsys assay was on average 0.200 log(10) IU/ml (LOA, -0.500, 0.800) higher than that using Architect, which was consistent across levels of CD4(+) cell count, presence of precore and YMDD mutations, and HBeAg status. A slightly larger mean between-assay difference was observed with genotypes A and G (0.196 and 0.201, respectively) versus HBV genotypes D and E (0.036 and 0.030, respectively). Mutations on the S region at position s120/s145 were the only determinant in which the mean between-assay difference in HBsAg quantification was lower than the null value (-0.078). In conclusion, the Elecsys assay, with automatic on-board dilution, is capable of quantifying serum HBsAg levels in HIV-HBV-coinfected patients, with very high correlation with the Architect assay.
authors.affiliation: Laboratoire de Virologie, Hôpital Saint-Louis, AP-HP, Paris, France.
authors.forename: Sarah
authors.initials: S
authors.lastname: Maylin
authors.forename: Anders
authors.initials: A
authors.lastname: Boyd
authors.forename: Constance
authors.initials: C
authors.lastname: Delaugerre
authors.forename: Fabien
authors.initials: F
authors.lastname: Zoulim
authors.forename: Fabien
authors.initials: F
authors.lastname: Lavocat
authors.forename: François
authors.initials: F
authors.lastname: Simon
authors.forename: Pierre-Marie
authors.initials: PM
authors.lastname: Girard
authors.forename: Karine
authors.initials: K
authors.lastname: Lacombe
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000627:therapeutic use; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D060085:Coinfection / Q000276:immunology / Q000821:virology; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy / Q000276:immunology; D006509:Hepatitis B / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000097:blood* / Q000276:immunology; D006513:Hepatitis B e Antigens / Q000276:immunology; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D063065:Organophosphonates / Q000627:therapeutic use; D011933:Reagent Kits, Diagnostic; D000068698:Tenofovir
chemical_list: D019380:Anti-HIV Agents; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D063065:Organophosphonates; D011933:Reagent Kits, Diagnostic; D000068698:Tenofovir; D000225:Adenine