Mutation analysis of hepatitis B virus polymerase gene sequence in chronic hepatitis B patients with virological rebound

Abstract

Objective To investigate the sequence of hepatitis B virus (HBV) polymerase gene in chronic hepatitis B (CHB) patients with virological rebound. Methods A total of 141 serum samples from patients with viral rebound were collected, and the polymerase gene of HBV was sequenced directly using polymerase chain reaction products. Among the recruited patients, 59 cases were diagnosed with chronic hepatitis B (CHB), 68 cases of liver cirrhosis and 14 cases of primary hepatocellular carcinoma. Adefovir dipivoxil (ADV) was administered for 51 cases, lamivudine (LAM) or telbivudine (LdT) for 39 cases, entecavir (ETV) for 10 cases and LAM or LdT switching to ADV for 41 cases. Comparison of mutation rates between groups were compared by χ2 test. Results Among these 141 patients, drug-resistant mutations were detected in 20 (20/51, 39.2%) of ADV-treated patients, 28 (28/39, 71.8%) of LAM- or LdT-treated patients, 3 (3/10) of ETV patients and 30 (30/41, 82.1%) of LAM/LdT followed by ADV treated patients. The most prevalent mutations was rtM204I/V/S (35.5%), followed by rtL180M (22.7%) and then rtA181T/V mutation (19.1%). Conclusions The resistant mutation rate is the highest in LAM or LdT followed by ADV sequential therapy, while the lowest in ETV therapy. This study suggests that physicians should select the antiviral drugs rationally. Key words: Hepatitis B virus; Virologicalrebound; Resistant mutation