Comparison between Elecsys HBsAg II and Architect assays for quantification of serum hepatitis B surface antigen in Chinese patients with chronic hepatitis B.

BACKGROUND: Chronic hepatitis B (CHB) is an important global health problem. Recent innovations have rendered quantification of serum hepatitis B surface antigen (HBsAg) a valuable tool in hepatitis B virus (HBV) disease management and for determining the effectiveness of drug treatment. The aim of the present study was to compare the performances of the Elecsys HBsAg II and Abbott Architect HBsAg assays in Chinese patients with CHB, with predominantly genotypes B and C. METHODS: A dilution protocol was developed for the Elecsys assay to allow quantification of HBsAg levels. Sera were obtained from patients with various HBV genotypes, including HBV mutants, and longitudinal samples were obtained from patients undergoing antiviral treatment. RESULTS: There was a significant overall correlation between the Elecsys and Architect assays (r = 0.9881; p < 0.001). There were good correlations between the results of the two assays in terms of HBsAg levels in CHB samples (r = 0.9625-0.9974), in samples with low HBsAg levels (r = 0.9722, p < 0.001), across two genotypes (HBV genotype B, r = 0.9758, p < 0.001; HBV genotype C, r = 0.9943, p < 0.001), in samples with YMDD mutations (r = 0.9625, p < 0.001), and in samples from patients receiving anti-HBV treatment (r = 0.9974, p < 0.001). Bland-Altman analysis showed a discordance between the assays in all tested patients with CHB of 0.09 log IU/mL. CONCLUSIONS: Mean HBsAg levels detected by the Architect assay were higher than those obtained by the Elecsys assay. There was a good correlation between the results of the Elecsys HBsAg II and Abbott Architect HBsAg assays in patients with CHB, especially those with genotype C.