The Clinical Significance Of Serum Hepatitis B Virus Covalently Closed Circular DNA Determination In Patients With Chronic HBV Infection

[Objective]To study the clinical significance of serum hepatitis B virus covalently closed circular DNA(HBV cccDNA) determination in patients with chronic HBV infection.[Methods]Serum HBV cccDNA levels were determined in 325 patients with chronic HBV infection using molecular-beacon Polymerase Chain Reaction technique.The relationship between serum HBV cccDNA,serum total HBV DNA and clinical parameters were analysed. Serum HBV cccDNA levels in 68 lamivudine-treated chronic hepatitis B patients were measured at regular intervals during treatment. The relationship between serum HBV cccDNA levels,antiviral efficacy of lamivudine and YMDD mutations was evaluated.[Results]Our results showed that serum HBV cccDNA levels were positively correlated with serum HBV DNA levels (r=0. 76, P <0. 01) .The positive rate of serum HBV cccDNA in hepatitis B e antigen (HBeAg )-positive patients was significantly higher than that in HBeAg -negative patients (55. 4% vs. 25. 6%, P <0. 001). The serum total HBV cccDNA levels in HBeAg-positive patients were greater than that in HBeAg-negative patients (5. 4±1.7logs vs. 3. 9±1.1logs , P =0. 012). Serum HBV cccDNA in patients with severe chronic hepatitis B (6. 1±1.2 logs) and moderate chronic hepatitis B (6. 4 ± 1.6 logs) were respectively greater than that in patients with mild chronic hepatitis B (4. 3 ± 0. 9 logs) . 68 patients with chronic hepatitis B received lamivudine therapy. 8 patients developed YMDD mutations during 48 weeks treatment.Compared to patients without YMDD mutations ,patients with YMDD mutations had significantly higher serum total HBV cccDNA (5. 9±1.4 logs vs. 4. 3 ±1.1 logs, P=0. 026) . Serum HBV cccDNA levels in complete responder, partial responder and non-responder group were 3. 9 ± 0. 7 logs, 4. 2 ± 0. 6logs and 5. 8 ± 0. 9logs .respectively. The HBV cccDNA concentration in non-responder group was...