Inter-method variability of hepatitis B surface antigen quantification in a cohort of Egyptian patients with chronic hepatitis B virus.

BACKGROUND AND STUDY AIMS: Hepatitis B (HB) surface antigen (HBsAg) levels can predict clinical and treatment outcomes in chronic HB virus (HBV) infection. We aimed to compare the performance of two different assays [Elecsys® (Roche) and Architect™ (Abbott)] for HBsAg quantification and evaluate HBsAg levels in the various immune phases in a cohort of Egyptian patients with chronic HBV.

PATIENTS AND

METHODS

Quantitative HBsAg by Elecsys® and Architect™ assays, measurement of routine biochemical and serological markers, and transient elastography were performed in 92 patients with chronic HBV. Results of the two assays and other tests were compared.

RESULTS

Ninety-two treatment-naive patients with chronic HBV, (70% males; mean age, 36.1 ± 10.5 years) were recruited from Cairo Fatemic Hospital. Patients were categorized as HBeAg positive (n = 22) and HBeAg negative (n = 70). The Architect™ and Elecsys® assays were significantly correlated (intraclass correlation coefficient: 0.913; 95% CI: 0.870-0.943; p < 0.001). However, Deming regression, Passing and Bablok, and Bland-Altman statistical analyses showed discordance among the assays. HBsAg levels by both assays were significantly higher in the HBeAg positive than patients with HBeAg-negative (p = 0.033 and 0.013, respectively). HBsAg levels in the Architect™ and Elecsys® assays were significantly higher in HBeAg-negative chronic hepatitis than in HBeAg-negative chronic infection (p = 0.002 and 0.004, respectively)

CONCLUSION

Both assays for qHBsAg were found to be simple and reproducible tests that could classify patients and provide additional evidence on the natural history of HBV.