RESUMO
The detection of hepatitis B virus (HBV) DNA plays a critical role in determining the level of viral replication in HBV-infected patients. However, how to select appropriate HBV DNA detection method, low-sensitivity (ls) and hypersensitivity (hs) remains unclear. In this study, hepatitis B surface antigen (HBsAg), hepatitis B e-antigen (HBeAg), alanine transaminase (ALT), aspartate transaminase (AST), and hs HBV DNA titers in serum of 5611 cases with suspected HBV infection were reviewed. Besides, the dynamic changes of HBV DNA and HBsAg in 85 chronic hepatitis B (CHB) patients receiving peginterferon α (PegIFNα) or entecavir (ETV) were observed. The results showed the positive rate of HBV DNA was 32.8%, of which low viral load (20 to 500 IU/mL) accounted for 51.8%. In the 5611 cases, when the HBsAg was less than 1000 IU/mL, the proportion of low viral load was 76.3%. Moreover, in patients receiving antiviral treatment, when HBsAg was less than 2000 IU/mL (PegIFNα) or HBsAg was less than 3500 IU/mL (ETV), the proportion of patients with low viral load was 79.5% or 78.0%, respectively. We developed a strategy of serum HBV DNA detection in HBV-infected patients. When HBsAg was negative, HBV DNA detection should be unnecessary. When HBsAg was 0.05 to 1000 IU/mL, hs HBV DNA should be detected in patients with abnormal level of ALT, AST, or HBeAg. While HBsAg was greater than or equal to 1000 IU/mL, ls HBV DNA was recommended. Moreover, the cutoff value of HBsAg increased during antiviral therapy of CHB patients. In conclusion, hs HBV DNA is of great value in HBV-infected patients with low viral load. HBV DNA detection methods should be selected reasonably according to the levels of HBsAg, HBeAg, ALT, and AST.