拉米夫定耐药患者乙型肝炎病毒P区变异及其特点

Characteristics of Hepatitis B Virus Polymerase Region Mutation in Lamivudine Resistant Patients

【目的】观察使用拉米夫定抗病毒治疗患者乙肝病毒（HBV）P区变异及特点，为临床拉米夫定耐药的预防提供依据。【方法】对52例服用拉米夫定患者进行研究，对其HBV聚合酶逆转录酶区基因进行分析。采用荧光定量PCR试剂进行HBV基因分型。通过巢式PCR引物扩增P区，扩增产物经纯化后进行测序分析。【结果】在52例拉米夫定耐药患者中，其平均年龄（33．6±13．4）岁，共有30例发现了HBVP区耐药位点变异，检出率为57．3％。M204I为主要的突变类型。其中发现P区变异的在病毒学反弹的、治疗中应答不佳的及停药后复发的患者中分别19例，6例，5例，三者变异发生率分别为82．6％，42．9％，33．3％，其变异发生率有显著差异（P〈0．05）。疗程在1年，2年及2年以上的，P区突变检出率分别为26．3％，72．7％，81．8％，三组之间比较有显著差异。P区突变组用药时间明显长于无P区突变组，分别为（27．7±19．9）个月，（13．9±7．6）个月（P〈0．005）。【结论】拉米夫定治疗后耐药患者HBVP区变异发生率也随着时间的延长而增高。且有P区变异的平均用药时间明显长于未检测到P区变异组，故在拉米夫定长期治疗过程中，应定期观察其耐药的产生，及时调整治疗方案，以维持临床疗效的稳定性。

[Objective] To observe the hepatitis B virus polymerase（HBV P） region mutation in patients trea- ted with lamivudine and its characteristics so as to provide the basis for the prevention of lamivudine resistance. [Methods] A total of 52 patients treated with lamivudine were enrolled in this study. HBV P gene was analyzed. Fluorescent quantitative PCR was used for HBV genotype. Nested PCR amplified P region. PCR products were purified for sequencing and analysis. [Results] In 52 lamivudine resistant patients with the average age of （33.6± 13.4） years old, 30 patients had HBV P region mutation. The detection rate was 57.3%. M204I was the major type of mutation. HBV P region mutation, virology rebound or poor treatment response and relapsed after with- drawal were found in 19 patients, 6 patients and 5 patients, respectively, and their mutation rates were 82.6%, 4：2.9% and 33.3%, respectively. There was significant difference in mutation rate（ P 〈0. 005）. The HBV P region mutation detection rate of patients with 1, 2 and more than 2 years of treatment course were 26.3%, 72.7% and 81.8%, respectively, and there was significant difference among 3 groups. The treatment duration of HBV P region mutation group was obviously longer than that in non-HBV P region mutation group[ （27.7 ± 19.9） vs （13. 9±7.6 months）, P 〈0. 005]. [Conclusion] The incidence rate of HBV P region mutation in lamivudine resistant patients increases with the increasing of treatment time. The average medication time of HBV P region mutation is obviously longer than that of non-HBV P region mutation. During the long-term treatment with lamivudine, regu- lar observation, drug resistance detection and prompt adjustment of treatment protocol should be done to maintain the stability of clinical efficacy.