Correlation between HBsAg level and HBV DNA titer during chronic hepatitis B treatment

AIM: Viral load is widely used as an indicator for the diagnosis and monitoring the treatment efficacy of chronic hepatitis B (CHB). Previous studies suggested that the quantity of hepatitis B surface antigen (HBsAg) in serum could be a surrogate marker of serum hepatitis B virus (HBV) DNA level. In this study, we aimed to investigate whether HBsAg level correlates with HBV DNA titer during CHB treatment. METHODS: Sera were collected from 47 CHB patients ［35 male, 12 female, mean age: (35±8) years］ treated for 48 weeks with a monotherapy (pegylated interferon alpha-2a, 18 patients; lamivudine, 15 patients) or a combination therapy (pegylated interferon alpha-2a and lamivudine, 14 patients). Serum samples were obtained at week 0 (just before the treatment), 4, 8, 24, 48 and week 72 (24 weeks after the treatment). HBV DNA was measured with real-time polymerase chain reaction (PCR). HBsAg was quantified with an automated chemiluminescent microparticle immunoassay. RESULTS: The titer of HBsAg correlated with the HBV DNA level in the 18 patients with monotherapy of pegylated interferon alpha-2a and the 14 patients with combination therapy (pegylated interferon alpha-2a and lamivudine). The significant correlation (canonical correlation=0.83) was found. However, no correlation in 15 patients with the monotherapy of lamivudine was observed. CONCLUSION: HBsAg titer correlates with HBV DNA level in CHB patients during the treatment with interferon or interferon and lamivudine, which can be a surrogate marker for monitoring the treatment efficacy.