拉米夫定耐药后阿德福韦酯治疗应答欠佳患者乙型肝炎病毒耐药变异模式

摘要

目的 观察拉米夫定(LAM)耐药后单用或联合阿德福韦酯(ADV)治疗应答欠佳患者HBV耐药变异模式. 方法收集15例LAM耐药后采用ADV治疗病毒学应答欠佳患者的血清,对HBV聚合酶逆转录区进行聚合酶链反应、扩增、克隆、测序,分析与耐药相关的变异模式.组间HBV DNA水平比较采用t检验.结果 单用ADV组检测出A181T+N236T、A181V和A181T 等模式的ADV耐药变异,而联合治疗组中主要检测出M204V+L180M、M204V+L180M+L229V、M204I+L80I和M204V+L180M+V207I等LAM耐药变异模式.另外,在联合治疗组的3份血清中,20%的克隆上同时出现对LAM和恩替卡韦耐药的变异,分别为M204I+L80I+T184I(2/10)、M204V+L180M+T184S(2/10)和M204V+L180M+G173L+S202G(2/10).两组中各有1份未检测出已知耐药变异的血清,在它们的测序结果中发现所有克隆均出现1269L变异,且其中单用组中所有克隆均出现P109S变异.联合治疗组和单用ADV组患者血清HBV DNA水平分别为(3.86±0.85)log10拷贝/ml和(5.71±0.94)log10拷贝/ml,差异有统计学意义(t=3.947,P<0.01).结论 LAM耐药后ADV治疗病毒学应答欠佳的患者中,单用ADV治疗容易筛选出A181T+N236T和A181V/T等ADV耐药变异模式,而联合ADV治疗组仍以M204V+L180M、M204V+L180M+L229V、M204I+L80I和M204V+L180M+V207I等LAM耐药变异模式为主.联合治疗时由于LAM的持续使用可选择出恩替卡韦耐药变异模式T184I/S和S202G;对于部分患者,1269L和P109S变异可能影响ADV治疗应答.%Objective To investigate the resistance mutation patterns of hepatitis B virus(HBV) during adefovir dipivoxil (ADV) monotherapy or combination therapy after lamivudine(LAM) resistance. Method Serum samples from fifteen patients with suboptimal viral response to ADV therapy after LAM resistance were collected. The RT region of HBV P gene was PCR-amplied, cloned and sequenced, and the mutation patterns in relation to resistance were analyzed. Results The ADV resistance mutation patterns of A181T+N236T, A181V, A181T were selected in ADV monotherapy group. The LAM resistance mutation patterns of M204V+L180M, M204V+L180M+L229V, M204I+L80I, M204V+L180M+V207I were detected in the combination therapy group. 20% of clones from three serum samples were detected double resistance to LAM and entecavir (ETV) in the combination therapy group, the resistance patterns were M204I+L80I+T184I(2/10), M204V+L180M+T184S (2/10), and M204V+L180M+G173L+S202G (2/10) respectively. I269L clones were detected in two serum samples from both two groups and P109S clones also detected in the one from monotherapy group. Conclusions In the patients with suboptimal viral response to ADV therapy after LAM resistance, the ADV resistance mutation patterns of A181T+N236T, A181V and A181T could easily be selected during ADV monotherapy; while in the patients with combination therapy, the LAM resistance mutation patterns of M204V+L180M, M204V+L180M+L229V, M204I+L80I, and M204V+L180M+V207I were predominant, the ETV resistance mutation T184I/S and S202G could be selected. The mutation patterns of I269L and P109S may impact the responses to ADV therapy in some patients.