987例乙型肝炎患者HBV-DNA P区多位点耐药突变分析及临床意义

目的分析乙型肝炎患者HBV-DNA P区基因突变情况、用药史及其临床意义。方法采用焦磷酸测序法,对368例经核苷(酸)类似物(NAs)治疗1年以上(用药组)及619例未用抗病毒药物治疗(未用药组)的乙型肝炎患者HBV-DNA P基因区9个NAs相关耐药突变位点进行检测,回顾性分析不同NAs耐药的突变形式,分析NAs治疗前HBV逆转录酶(RT)基因自然变异的发生率。结果 368例中94例出现基因耐药变异,变异模式以经典突变L180M、M204V/I、A181V/T、N236T突变为主,其次为V173L、S202G/S、T184L、I169T突变,M204V多以联合L180M突变的形式存在,其中235例服用单种NAs有48例发生变异,多位点(3个及以上耐药位点)突变5例(10.42%),133例服用多种NAs有46例发生变异,多位点突变19例(41.30%),多药使用者发生多位点变异率明显高于单药使用者(χ2=8.38,P0.05)。368例患者中多位点变异组(A组)与少于三个位点变异组(B组)的年龄、HBVDNA、ALT无明显差异。619例中51例出现基因耐药变异(8.24%)。结论 HBV感染者存在少量自然变异位点。长期应用NAs可筛选出HBV-DNA P基因区的相关耐药变异且耐药变异复杂,服用多种NAs(特别是序贯治疗)容易发生基因耐药变异且易发生多位点变异。长期应用NAs的乙型肝炎患者需定期检测基因耐药情况并及时干预,避免临床反跳的发生。

Analysis and clinical significance of drug-resistant multi-site mutation of P area of HBV genome in 987 patients with HBV infection

Objective To investigate clinical significance,previous antiviral therapy history and mutation patterns of P area of HBV genome in patients with HBV infection.Methods Pyrosequencing method was used to detect the 9 sites in the HBV-DNA P gene of nueleos（t）ide analogue （NAs） related resistance mutations.Three hundred and sixty-eight patients were treated with NAs at least one year （treatment group） and 619 patients without antiviral drugs treatment （non-treatment group）.Previous antiviral therapy histories and mutation patterns of each patient were retrospectively analyzed.At the same time,the incidence of HBV pre-existing mutation was explored.Results Ninety-four patients were found to have mutations associated with drug resistance and the major mutations were M204V/I,L180M,A181V/T,N236T,adding a small amount of V173L,S202G/S,T184L,I169T mutation.M204V usually companied by L180M mutations.The incidence rate of multi-site （three or more site mutations） mutations in the patients with multi-NA history （41.30%） was higher than those with single-NA history （10.42%） （Х^2 =8.38,P 〈0.05）.There were no differences of HBV-DNA,ALT,age in the multi-site mutation group （group A） and the less than three site mutations group （group B）.Of 619 previously untreated with NAs patients,51 cases （8.24%） were found to have pre-existing mutations.Conclusion There are some cases with pre-existing mutations.Long-term treatment with NAs can lead HBV-DNA produce complex NAs related resistance mutations.The sequential therapy can screen out the multi-site mutation virus.HBV drug-resistant mutations should be detected regularly and suitable measures should be taken to prevent the occurrence of clinical breakthrough.