Abstract: Objective To study the clinical significance of variation of hepatitis B virus C region in patients with occult hepatitis b virus infection (OBI). Methods Clinical data of 80 OBI patients admitted and treated in our hospital from March 2017 to March 2019 were retrospectively analyzed. After admission (before treatment), 7mL of fasting venous blood was extracted 2 ~ 3 days in the morning to detect hepatitis b E antigen (HBeAg), HBV-DNA, core antibody (anti-HBc) and hepatitis b virus C region variation. Analysis of hepatitis b virus C region variation of HBeAg (+) and HBeAg (-) patients, as well as hepatitis b virus C region variation in patients with different HBV-DNA content HBeAg (-). Finally, the distribution of anti-HBc (+) in HBeAg (-) hepatitis b virus variant patients was analyzed. Results In 80 patients with OBI, HBeAg (+) accounted for 55.00% and HBeAg (-) 45.00%.The mutation rate of HBeAg (-) group was 75.00%, which was significantly higher than that of HBeAg (+) group (34.09%, P<0.05). The variation rates of hepatitis b virus C region in patients with different HBV-DNA content HBeAg (-) were 100.00%, 78.95%, and 16.67% respectively, with statistically significant differences between each group (P<0.05). The anti -HBc (+) rate was 81.48% in 27 patients with HBeAg (-) hepatitis b virus variant in region C. Conclusion HBV C region mutation in OBI patients is closely related to disease progression and prognosis, so we should pay attention to HBV C region mutation in the diagnosis and treatment of OBI.

Key words: Occult hepatitis B virus infection, Hepatitis B virus deoxyribonucleic acid, C region mutation