拉米夫定治疗乙型肝炎病毒B、C基因型疗效比较

目的 研究乙型肝炎病毒(HBV)基因型对拉米夫定抗病毒疗效的影响。 方法 回顾调查235例拉米夫定治疗组和对照组患者的临床资料。 结果 135例患者接受拉米夫定抗病毒治疗,对照组100例。HBV优势基因型是B型和C型,拉米夫定治疗组有效率分别为92.9％和75.9％(x2=6.628,P<0.05),对照组有效率分别为9.8％和8.5％(P>0.05);YMDD变异发生率治疗组为3.6％和16.5％(x2=5.508.P<0.01)。结果发现,B基因型、丙氨酸氨基转移酶升高、HBV DNA低水平是抗病毒应答预测因素。 结论B基因氆HBV对拉米夫定的应答率优于C型,YMDD变异发生率低于C型,基因型是影响拉米夫定疗效和决定变异的重要因素之一。     

乙型肝炎病毒基因型、YMDD变异与拉米夫定治疗后HBV DNA反弹关系的研究

目的探讨HBV基因型、YMDD变异与拉米夫定抗病毒治疗后HBV DNA反弹的关系。方法应用多引物对巢式PCR法、PCR-序列分析法检测拉米夫定治疗的27例乙型肝炎患者和19例从未用过抗病毒治疗的患者HBV基因型和P区（YMDD）的突变位点。结果在27例HBV DNA反弹的患者中，13例（48．15％）检出YMDD变异，而对照人群无YMDD变异（P〈0．05）。YMDD变异的位点为rtM204V／I（C区）±rtL180M（B区）；在治疗组YMDD变异的患者中，B、C基因型构成比（46．15％和59．26％）与对照组（53．85％和68．42％）比较无显著性差异（P〉0．05）。结论YMDD变异是拉米夫定治疗后出现耐药导致HBV DNA反弹的主要原因；YMDD变异的常见位点依然为rtM204V／I（C区）±rtL180M（B区）；YMDD变异在B、C基因型病人中无差别。     

乙型肝炎病毒基因型与拉米夫定疗效关系的研究

探讨乙型肝炎病毒(HBV)基因型与拉米夫定治疗慢性乙型肝炎(CHB)疗效的关系。采用PCR、核酸杂交和酶联显色技术对CHB进行HBV基因分型,观察123例(B型93例和C型30例)CHB患者拉米夫定治疗1年后肝功能、病毒学指标和YMDD变异的变化。ALT复常率为92.47%,HBeAg阴转率为27.96%,HBVDNA阴转率为82.80%,有效应答率为89.25%,与C基因型相比差异有显著性(P<0.05或P<0.005)。B型YMDD变异的发生率为9.68%,显著低于C型的26.67%(P<0.05)。B型对拉米夫定的抗病毒疗效高于C型,YMDD变异的发生率则低于C型。HBV基因型是影响拉米夫定疗效和变异的重要因素之一。     

乙型肝炎病毒前C基因区变异对YMDD变异毒株复制活性的影响

目的调查接受拉米夫定治疗的乙型肝炎病毒（HBV）感染者中HBV前C基因区终止密码变异（A1896，PC）和基本核心启动子变异（BCP，T1762／A1764）对YMDD变异毒株复制活性的影响。方法应用聚合酶链反应-限制性片断长度多态性（PCR—RFLP）法对197例接受拉米夫定治疗后发生YMDD耐药变异的患者进行HBV基因型、PC及BCP变异检测，并用实时荧光定量法对所有患者血清HBVDNA进行定量。结果197例YMDD变异株感染者中B基因型占51．8％，C基因型占48．2％；有61例（31．0％）发生PC变异，69例（35．0％）发生BCP变异；PC变异在B基因型中的发生率明显高于C基因型（X^2=8．433，P=0．004），而BCP变异在C基因型中的发生率显著高于B基因型（X^2=16．83，P〈O．001）；发生PC或BCP变异的HBV感染者，其血清中HBVDNA水平与野生株相比差异均无统计学意义。结论HBV前C基因区的PC或BCP变异与基因型具有相关性，但这两种变异对YMDD变异株感染者的血清病毒水平均无影响。     

秦皇岛市136例慢性乙型肝炎患者拉米夫定的疗效及其与HBV基因型的关系

目的:探讨秦皇岛市慢性乙型肝炎(CHB)患者拉米夫定治疗疗效与基因型的关系。方法:136例CHB患者口服拉米夫定,100mg/次,1次/d,疗程48周,用药前采用PCR方法测定乙型肝炎病毒(HBV)A～D基因型。结果:秦皇岛市CHB患者基因型以C型为主,占75.74%,其次为B基因型占16.91%,B/C混合型占7.35%,B基因型在拉米夫定抗病毒治疗48周时显示HBV DNA阴转率、HBeAg血清转换率、ALT复常率、治疗有效率4方面均高于C型及B/C基因型(P0.05),B基因型HBV感染者有较低的YMDD变异发生率。结论:拉米夫定抗病毒疗效与基因型有关,HBV基因型测定可作为预测拉米夫定抗病毒疗效的指标。     

e抗原阳性慢性乙型肝炎患者感染病毒的基因型与抗病毒治疗疗效的关系

目的 探讨HBV基因型与抗病毒治疗疗效的关系。方法 应用PCR-微板核酸分子杂交ELISA法检测90例HBeAg阳性CHB患者的HBV基因型,对其中41例患者给予拉米夫定（100 mg／d）抗病毒治疗48周,49例患者给子干扰素α（3 MU／次,隔日1次）抗病毒治疗48周,治疗前、治疗过程中和治疗结束时分别检测血清生化指标（ALT）、病毒学血清标志物（HBeAg和抗-HBe）和HBV DNA水平。结果 90例CHB患者中HBV B基因型者16例,C基因型者74例。41例患者应用拉米夫定治疗,感染B和C基因型患者48周时对拉米夫定治疗应答率分别为33.3％和20%,差异无统计学意义;49例患者应用干扰素α治疗,48周时感染基因B型患者的ALT复常率、HBeAg消失率和HBV DNA阴转率均高于感染基因C型患者（分别为60.0％和20．5％,50．0％和17．9％, 50．0％和17．9％）,两组比较差异有统计学意义,但HBeAg血清转换率差异无统计学意义。结论 基因B和C型对拉米夫定抗病毒治疗的疗效无影响,基因B型对干扰素α治疗的疗效优于C型。     

对拉米夫定耐药患者乙型肝炎病毒基因型与病毒载量及其核苷酸序列分析

目的探讨对拉米夫定耐药患者HBVB、C基因型的病毒载量及其核苷酸序列突变等病毒学特性的差异。方法采用ELISA、实时荧光定量PCR和DNA序列分析的方法，检测53例对拉米夫定耐药患者的HBV基因型、病毒载量及其C、P基因核苷酸序列，并将测序结果与基因库中标准HBV基因型序列进行比较分析。结果53例拉米夫定耐药患者中，B基因型22例，C基因型31例；C基因型的YIDD突变率明显高于B基因型（87．1％比36．4％，P〈0．01），且C基因型的病毒载量为（7．71±0．80）lg拷贝／mL，明显高于B基因型的（6．97±0．77）lg拷贝／mL（P〈0．01）；而B基因型的YVDD突变率和前C区突变（G1896A）明显高于C基因型（分别为63．6％比12．9％、77．3％比32．3％，P值均〈0．01）。B、C基因型的核心启动子突变（T1762／A1764）比较，差异无统计学意义（31．8％比35．5％，P〉0．05）。前C区／核心启动子的突变影响拉米夫定耐药患者的病毒水平。结论拉米夫定耐药患者HBV B、C基因型的YMDD基序分别以YVDD和YIDD变异为主，且基因型C的病毒载量比B基因型要高；B基因型易出现前C区突变（G1896A）。     

RtL164V,一个可能与拉米夫定耐药相关的突变

目的 进一步了解HBV P基因结构与拉米夫定的疗效关系.方法 一步法扩增HBVP基因后进行测序,对比拉米夫定治疗应答,无应答和突破患者治疗前后血清HBV P基因结构的变化.结果 在无应答和突破患者中,2例B基因型和1例C基因型转变为B、C混合型HBV感染;1例患者血清HBV发生B→C基因型转换.3组中部分患者治疗前血清中检出YMDD变异株HBV,所有8例治疗无应答和突破患者在治疗过程中均出现YMDD变异.所有无应答患者治疗前后和突破患者突破时的血清HBV均出现rtL164V变异,而在应答者中未见.突破和无应答患者逆转录酶(rt)保守区还出现rt191L、rtK168R、rtH2ML、rtS256C 4个氨基酸替代.结论 YMDD基因序列变异不是产生拉米夫定临床耐药的惟一原因,rtL164V变异可能是一个新的与拉米夫定耐药相关的突变.     

HBV基因型及P基因变异与拉米夫定耐药的关系

为探讨拉米夫定耐药与HBV基因型和P基因变异的关系,用基因测序的方法分析基因型与YMDD变异,用荧光定量的方法,检测HBVDNA定量,研究结果表明C基因型比其它基因型更易耐药,耐药的问题不仅仅是 YMDD变异,P基因可能诱导其它基因的变异,导致拉米夫定抗病毒治疗的疗效减低。     

慢性乙型肝炎拉米夫定耐药患者HBV基因型及ALT变化的观察

观察慢性乙型肝炎患者用拉米夫定治疗后HBVP基因变异与不同HBV基因型感染及HBV DNA复升水平和转氨酶变化.收集51例慢性乙型肝炎患者用拉米夫定治疗52-78周后发生YMDD变异的血清标本,对照组128例未用拉米夫定治疗的慢性乙型肝炎患者血清标本,应用聚合酶链反应方法,测定HBV DNA基因型;用限制性片段长度多态性分析方法(PCR RELP)测定HBV DNA YMDD变异;同时进行HBV DNA定量分析.结果显示51例拉米夫定治疗后HBV DNA基因变异患者以B型和C型为主,分别为10例(19.6%)和39例(76.47%),B C混和型2例(3.92%),未见其它基因型.拉米夫定治疗引起HBVDNAYMDD变异可以发生在不同HBV基因型感染的慢性乙型肝炎患者中,与对照组比较二者没有显著性差异.     

HBV genotype B is associated with better response to interferon therapy in HBeAg(+) chronic hepatitis than genotype C

Hepatitis B virus (HBV) genotype and precore/core promoter mutations have been implicated in spontaneous and interferon alfa (IFN-alpha)-related hepatitis B e antigen (HBeAg) seroconversion. We performed a retrospective analysis of a previously reported randomized controlled trial to determine the effects of HBV genotype and precore/core promoter mutations on IFN-alpha response in patients with HBeAg-positive chronic hepatitis. Clinical data and stored sera from 109 (95%) patients in the original trial were analyzed. Seventy-three patients received IFN-alpha and 34 received no treatment (controls). Almost all patients had HBV genotypes B (38%) and C (60%). Antiviral response was achieved in 39% and 17% of IFN-alpha-treated patients (P =.03) and in 10% and 8% of untreated controls (P =.88) with HBV genotype B and C, respectively. Multivariate analysis identified HBV genotype B, elevated pretreatment alanine aminotransferase (ALT) levels, and low pretreatment HBV-DNA levels but not IFN-alpha treatment as independent factors associated with antiviral response. Among the 66 patients with elevated pretreatment ALT level, antiviral response was achieved in 57% and 21% of IFN-alpha-treated patients (P =.019), and in 25% and 8% of untreated controls (P =.45) with HBV genotype B and C, respectively. Multivariate analysis showed that genotype B and low pretreatment HBV-DNA levels were independent predictors of antiviral response. In conclusion, our data showed that HBV genotype B was associated with a higher rate of IFN-induced HBeAg clearance compared with genotype C. Stratification for HBV genotypes should be considered in future clinical trials of antiviral therapy of chronic hepatitis B.     

A case-control study of response to lamivudine therapy for 2 years in Japanese and Chinese patients chronically infected with hepatitis B virus of genotypes Bj, Ba and C.

BACKGROUND/AIMS: In eastern Asian countries, hepatitis B virus (HBV) genotype Ba (HBV/Ba), HBV/Bj and HBV/C are prevalent. The aim was to investigate the response or resistance to lamivudine therapy among patients with different HBV genotypes. METHODS: Of 67 Japanese and Chinese patients with chronic hepatitis B, 18 patients with HBV/Bj, 15 with HBV/Ba and 34 with HBV/C were selected for a case-control study matched according to gender and age. All the patients were treated with lamivudine for 2 years and evaluated the response or emergence of the YMDD mutation at year 2 during the treatment. HBV genotypes were detected by the restriction fragment length polymorphism. The YMDD mutation was detected by the direct sequencing after amplification by PCR. RESULTS: At year 2 during therapy, 44.8% of the patients showed normalization of ALT and undetectable HBV DNA (favorable response), 35.8% developed the YMDD mutation. There was no significant difference of response to the therapy among the three genotype groups. The emergence of the YMDD mutation was associated with HBV/C. By the multiple logistic regression analysis, however, the significant factor of a favorable response was a higher pretreatment ALT level and negative HBeAg status and the significant factor of the emergence of the YMDD mutation was HBV/C. CONCLUSIONS: Higher pretreatment ALT level, HBeAg status or HBV genotype may affect the response or resistance to lamivudine therapy.     

YMDD mutations and genotypes of hepatitis B virus in northern China

The objective of this research was to determine the relationship between YMDD mutations and the genotypes of hepatitis B virus (HBV) during lamivudine treatment. HBV genotypes were determined by nested PCR with 6 pairs of HBV genotype-specific primers (A to F) in serum specimens from 142 hepatitis B patients receiving lamivudine antiviral therapy. YMDD mutations were detected by fluorescent hybridization bioprobe PCR and melting curve assay (FH-PCR-MC). Among 142 serum specimens, 13 samples were genotype B (9.2%), 125 samples were genotype C (88%), 4 samples were genotype D (2.8%), and 80 YMDD mutations were found. The YMDD mutation rates were 69.2 and 54.4% in genotype B and genotype C, respectively. There was no significant difference in the YMDD mutation rate between genotypes B and C. Nine genotype B sera with YMDD mutations were found, including 2 YIDD mutations and 7 YVDD (M + V) mutations. Sixty-eight genotype C sera with YMDD mutations were found, including 34 mutations I (M + I) and 17 mutations V (M + V). There was a significant difference in the YMDD mutation types between genotypes B and C. Our results suggested that the YMDD mutation rate was 56.3% in patients treated with lamivudine for 2-4 years. YIDD was the main mutation type. The YMDD mutation rate showed no significant difference between HBV types B and C (P > 0.05), while the YMDD mutation types showed a significant difference between HBV types B and C in Northern China (chi2 test = 4.6, P < 0.05).     

Clinical characteristics and distribution of hepatitis B virus genotypes in Guangxi Zhuang population

AIM: To investigate the distribution of HBV genotypes and their YMDD mutations in Guangxi Zhuang population, China, and to study the relationship between HBV genotypes and clinical types of HB, ALT, HBV DNA, HBe system as well as the curative effect of Lamivudine (LAM) on hepatitis B. METHODS: A total of 156 cases were randomly chosen as study subjects from 317 patients with chronic hepatitis B (CHB). HBV genotypes were determined by PCR-microcosmic nucleic acid cross-ELISA. YMDD mutations were detected by microcosmic nucleic acid cross-nucleic acid quantitative determination. HBV DNA was detected by fluorescence ratio PCR analysis. LAM was given to 81 cases and its curative effect was observed by measuring ALT, HBV DNA load, HBeAg, and HBeAg/HBeAb conversion rate. RESULTS: HBV genotypes B, C, D, and non-classified genotypes were found in Guangxi Zhuang population, accounting for 25.6%, 47.4%, 58.3%, and 16.0%, respectively. Seventy-four cases were CD-, CB-, BD-mixed genotypes (47.7%). Forty-six (29.5%) cases had YMDD mutations. Genotype B was mostly found in mild and moderate CHB patients. Genotypes C, D and mixed genotype mostly occurred in severe CHB cases. Genotypes D and CD HBV-infected patients had higher ALT and HBV DNA than patients with other types of HBV infection. There was no significant difference among the genotypes in YMDD mutations, clinical types, ALT and HBV DNA level. Non-classified types geno had a significantly lower positive rate of HBeAg than other genotypes (X2=12.841,P<0.05). There was no significant difference in ALT recovery rate, HBV DNA load, HBeAg, and HBeAg/HBeAb conversion rate, 48 wk after LAM treatment between groups of genotypes D, CD, and non-classified type. CONCLUSION: Genotypes B, C, and D, non-classified and mixed genotype of HBV are identified in the Guangxi Zhuang population. Variations in genotypes are associated with clinical severity and serum ALT levels, but not with YMDD mutation or HBV DNA load. Therapeutic effects of LAM on clinical parameters are not influenced by differences in genotypes. Further studies are needed to gain an in-depth understanding of the relationship between HBV genotypes and serum HBeAb and HBeAg.     

B和C基因型乙型肝炎病毒对阿德福韦酯治疗的病毒学应答比较

目的 阐明不同基因型HBV对阿德福韦酯治疗反应是否存在差异.方法 首先利用型特异引物PCR法结合型特异核苷酸分析法检测HBV基因型,然后根据基因型对阿德福韦酯Ⅲ期临床资料进行分析及统计学处理(计量资料用t检验,计数资料用卡方检验).结果 177例临床标本检出B基因型HBV感染者102例,C基因型感染者65例,B+C混合型感染者6例,B+D混合型感染者4例.治疗第12、24周时,B基因型组和C基因型组血清HBV DNA下降均值分别为2.2log10>拷贝/ml、2.1log10拷贝/ml和2.7log10拷贝/ml、2.4log10拷贝/ml,两组差异均无统计学意义(P>0.05),第48周时两组HBV DNA分别下降3.6log10拷贝/ml和3.1log10拷贝/ml,差异有统计学意义(P<0.05).治疗结束时(48周)B基因型组和c基因型组分别有43例(42.2%)和22例(33.8%)出现血清HBV DNA转阴,差异有统计学意义(P<0.05);两组患者HBeAg阴转率抗-Hbe血清转换率分别为30.4%、29.2%和21.6%、20.0%,差异无统计学意义(P>0.05).两组患者血清ALT复常率在治疗第12、24、36周和48周时分别为35.3%、33.9%,51.0%、53.9%,63.4%、61.5%和83.3%、81.5%,各时间段两组ALT复常率差异均无统计学意义(P>0.05).结论 阿德福韦酯治疗慢性乙型肝炎48周时,部分病毒学指标(如血清HBV DNA下降均值和HBV DNA阴转率)B基因型优于C基因型HBV感染者.但由于阿德福韦酯起效较慢,抑制病毒作用相对较弱,有必要延长治疗时间进一步证实这一现象.     

HBV基因型与阿德福韦酯抗病毒疗效的关系

目的 探讨HBV不同基因型对阿德福韦酯抗病毒疗效的影响.方法 选取42例应用阿德福韦酯治疗的慢性乙肝患者作为研究对象,观察治疗24周及48周时抗病毒疗效.采用型特异性引物进行巢式PCR,对患者血清中的HBV进行基因分型,采用荧光定量PCR检测患者血清HBV DNA复制水平,HBV血清病毒标志物采用双抗体夹心ELISA法检测.结果 42例慢性乙肝患者的HBV基因型分布为:B型23例,C型10例,B C混合型9例,未发现A、D、E、F基因型.不同基因型患者治疗前HBVDNA水平无统计学差异(P＞0.05).HBV基因型B型、C型和B C混合型患者治疗24周及48周时HBV DNA载量的变化、丙氨酸氨基转移酶(ALT)复常及HBeAg血清转换均无统计学差异(P＞0.05).结论 HBV基因型B型或C型对阿德福韦酯治疗的病毒学应答和生化应答相当,提示HBV基因型可能对阿德福韦酯的疗效无影响.