Abstract: Objective To investigate occult hepatitis B virus infection (OBI).Methods From August 2016 to March 2017, 1570 serum samples were collected continuously from hepatitis B surface antigen (HBsAg) negative patients who had at least any other positive marker in hepatitis B virus (HBV) markers. Patients with only HBsAb positive were excluded. High sensitive nucleic acid detection, full-automatic magnetic beads nucleic acid extraction and fluorescence quantitative polymerase chain reaction were used for HBV DNA quantitative detection. According to the instructions, HBV DNA >20 IU/mL was defined as positive. Meanwhile, Roche CAP/Prep HBV detection system was used to check the results. Results There were 71 HBV DNA-positive specimens in 1570 specimens, of which 49 were males and 22 were females. All cases were divided into 5 groups according to the diagnosis, including 506 cases of hepatitis, 399 cases of liver cirrhosis, 41 cases of liver space occupying lesion, 188 cases of liver cancer and 436 cases of other diagnoses. Of the 71 HBV DNA positive specimens, there were 31 cases of hepatitis (6%), 7 cases of liver cirrhosis (2%), 3 cases of liver space occupying lesion (7%), 16 cases of liver cancer (8%) and 14 other cases (3%). Moreover, 7 of the 71 HBV DNA positive specimens were from health examination.Conclusion OBI can occur in the population especially develop liver occupying lesion and liver cancer, and its screening should also be done in healthy people.

Key words: Occult hepatitis B virus infection, Hepatitis B surface antigen, Hepatitis B virus DNA