慢性乙型肝炎病毒感染患者血清及肝组织中抗幽门螺杆菌抗体及特异性基因分析

目的 对慢性乙型肝炎病毒(HBV)感染患者血清抗幽门螺杆菌(Hp)IgG(抗Hp-IgG)阳性率进行流行病学调查,同时对患者肝组织进行Hp特异性基因检测,探讨Hp在肝病发生、发展中的作用.方法 病例对照研究中共纳入502例HBV感染患者和性别、年龄相匹配的429名健康对照者.应用酶联免疫吸附(ELISA)法进行血清抗Hp-IgG检测.同时用针对螺杆菌菌属特异性16S rRNA基因的通用引物对其中56例肝穿刺活检组织进行基因扩增,并对该基因阳性者进一步应用Hp cagA、vacA和glmM基因特异引物进行扩增.结果 HBV感染患者血清抗Hp-IgG阳性率为63.9%,显著高于健康对照者(43.4%,P<0.05),其中肝癌组的阳性率最高(29/36,80.6%),其次为肝硬化组(64/83,77.1%),两组均显著高于慢性乙型肝炎组(228/383,59.5%,P<0.01).56例行肝穿刺活检患者中,35例肝组织中发现螺杆菌菌属特异性16S rRNA基因,其中肝硬化组17例,肝癌组7例,慢性乙型肝炎组11例.进一步的扩增结果 证实35例中21例为Hp DNA.结论 HBV感染患者血清抗Hp-IgG阳性率显著高于健康对照者.HBV感染患者肝组织中除存在Hp DNA外,可能还存在其他螺杆菌DNA.螺杆菌在慢性乙型肝炎向肝硬化和肝癌的发展过程中可能发挥致病作用.     

原发性肝癌组织中螺杆菌感染状况分析

目的对原发性肝癌患者肝组织内螺杆菌菌属特异性16S rRNA基因检测,分析螺杆菌感染与原发性肝癌发生、发展的关系。方法对36例原发性肝癌患者的肝组织应用螺杆菌菌属特异性16S rRNA基因的通用引物进行基因扩增及微需氧分离培养。结果 36例原发性肝癌患者的肝癌组织DNA中,有25例发现了螺杆菌菌属特异性16S rRNA基因,而23例正常肝组织仅有3例阳性,两组比较有显著差异(P<0.001)。对两组患者肝组织微需氧分离培养均未发现可疑菌落生长。结论原发性肝癌患者的肝组织中存在螺杆菌感染。螺杆菌在原发性肝癌的发展过程中可能发挥重要作用。     

肝癌患者肝组织中螺杆菌感染的研究

目的　探讨螺杆菌感染是否与人类肝癌的发生相关。方法　选取经病理诊断的肝癌组织及癌旁组织 2 0例为研究对象 ,非肝癌组织 16例作对照 ,采用聚合酶链反应 (PCR)扩增螺杆菌 16SrRNA基因 (16SrDNA)检测螺杆菌 ,扩增产物经Southern杂交证实 ,并对部分标本的PCR产物进行测序及同源比较。阳性者再扩增幽门螺杆菌 (H pylori)的特异基因 (2 6 -kDa蛋白 )和相关功能基因 (cagA、vacA、glmM、rps4 )来验证是否为该菌。结果　 4 0 % (8/ 2 0 )的肝癌组织中发现螺杆菌 16SrD NA存在 ,其对应的癌旁组织大部分亦阳性 (7/ 8) ,而非肝癌组无一例阳性 (P <0 0 1)。所有PCR产物用Southern杂交得到证实。 6例测序及同源比较显示 ,肝癌组织中的螺杆菌 16SrDNA序列与H pylori的 16SrDNA序列有 98 5 %～ 99 0 %的同源性。阳性标本中 2 6 -kDa基因大部分亦阳性 (7/ 8) ,但仅 2例扩增出cagA基因 ,2例扩增出glmM基因 ,一直未扩增出vacA基因和rps4基因。 结论　肝癌患者肝组织中螺杆菌感染率较高 ,它与肝癌的发生可能存在某种联系。     

慢性乙型肝炎患者幽门螺杆菌感染状况及肝组织螺杆菌属特异性16SrRNA基因分析

目的分析慢性乙型肝炎患者幽门螺杆菌(Hp)感染状况及肝组织螺杆菌属特异性16Sr RNA基因特点。方法纳入维吾尔族CHB患者60例和健康维吾尔族体检者80例,采用14C-尿素呼气试验检测H pylori阳性感染,常规进行肝穿刺,采用PCR法检测肝组织螺杆菌16Sr RNA基因水平。结果慢性乙型肝炎每分钟衰变数(14C-UBT)阳性率为85.00%,显著高于对照组[60.24%,P0.01];在所谓的60例慢性乙型肝炎患者中,经肝组织学检查,发现慢性乙型肝炎46例,肝硬化14例;在46例CHB和14例肝硬化患者肝组织DNA进行16 Sr RNA基因检测,结果 40例(86.96%)CHB和13例(92.86%)肝硬化患者16 s RNA阳性,两组差异无统计学意义(x2=0.363,P0.05);轻度、中度与重度CHB患者肝组织16 s RNA检出率亦无统计学差异(x2=1.348,P=0.510)。结论慢性乙型肝炎患者幽门螺杆菌感染率较高,但肝组织螺杆菌属特异性16Sr RNA检出率与乙型肝炎患者肝组织炎症或纤维化程度未显示出显著性关联。     

原发性肝癌组织中螺杆菌属16S rRNA基因的检测及意义

目的探讨原发性肝癌（HCC）组织中螺杆菌感染情况。方法选取经病理诊断的28例HCC患者的肝癌组织为实验组，22例非肝癌肝病患者肝组织和25例胃癌患者胃癌组织作对照组。采用聚合酶链反应（PCR）扩增螺杆菌属16S rRNA基因、幽门螺杆菌相关功能基因空泡毒素基因（vacA）和细胞毒素相关基因（cagA），16S rRNA的扩增产物经Southern杂交确认，并将PCR产物进行测序及同源性比较。结果28例HCC标本中有17例检出螺杆菌属16S rRNA基因，阳性率为60．7％；25例胃癌标本有18例检出螺杆菌16S rRNA，阳性率为72．0％；其他肝病组未扩增出16S rRNA基因。16Sr RNA PCR产物经Southern杂交证实为幽门螺杆菌。序列测定表明，肝癌和胃癌组织中的螺杆菌16S rRNA序列与幽门螺杆菌序列有97．8％的同源性。肝癌组相关功能基因有3例cagA基因阳性，胃癌组有2例cagA基因阳性，均未扩增出VacA基因。提示，幽门螺杆菌菌株的基因型多为Ⅱ型，而少数为Ⅰ型。结论HCC患者肝组织中存在螺杆菌感染且感染率较高。螺杆菌感染与HCC可能存在相关性。     

肝螺杆菌感染与人类原发性肝细胞癌的相关性研究

目的本研究旨在了解肝肠源性螺杆菌是否存在于肝细胞癌患者的胆汁内,探讨此菌与肝癌的相关性。方法收集经病理确诊的47例原发性肝细胞癌患者及24例结肠直肠癌肝转移患者的胆汁标本。使用特定16SrRNA引物的聚合酶链式反应(PCR)及DNA测序检测胆汁标本中的螺杆菌属及肝螺杆菌特异性16SrRNA,并使用酶联免疫吸附法(ELISA)检测胆汁标本中的肝螺杆菌抗体。结果 47例原发性肝细胞癌患者胆汁标本中有12例(25.5%)检测出肝螺杆菌特异性16SrRNA,15例(31.9%)检测出抗肝螺杆菌抗体;24例结肠直肠癌肝转移患者胆汁标本中只有1例(4.2%)检测出肝螺杆菌特异性16SrRNA基因,3例(12.5%)检测出抗肝螺杆菌抗体(P<0.05)。结论原发性肝细胞癌患者可检测出肝螺杆菌,这可能与肝细胞癌的发病机制有一定联系。     

布鲁氏菌和幽门螺杆菌等6种病原菌16S rRNA和cagA等基因的克隆与鉴定

目的克隆并鉴定布鲁氏菌的16SrRNA、支原体的16SrRNA、泰泽氏菌的16SrRNA、空肠弯曲菌的flaA、肝螺杆菌的flaB和幽门螺杆菌的cagA基因,为建立实时荧光定量PCR检测方法作准备。方法设计、合成布鲁氏菌的16SrRNA、支原体的16SrRNA、泰泽氏菌的16SrRNA、空肠弯曲菌flaA、肝螺杆菌flaB和幽门螺杆菌的cagA基因的特异性引物;PCR扩增、克隆16SrRNA、flaA、flaB和cagA基因;对重组质粒进行酶切鉴定、PCR鉴定和测序分析。结果布鲁氏菌的16SrRNA、支原体的16SrRNA、泰泽氏菌的16SrRNA、空肠弯曲杆菌的flaA、肝螺杆菌的flaB和幽门螺杆菌的ca-gA基因PCR扩增产物分别在612bp、600bp、922bp、637bp、1545bp和1168bp处出现特异性目的条带,结果均与预期扩增的目的片段大小一致。将PCR产物分别与pMD18-T载体连接并转化感受态细菌大肠埃希菌JM109。对重组质粒pT-BC16SrRNA、pT-MP16SrRNA、pT-CP16SrRNA、pT-CJflaA、pT-HHflaB和pT-HPcagA分别进行酶切鉴定及PCR鉴定,结果均可见特异性目的条带。测序结果显示,布鲁氏菌的16SrRNA、支原体的16SrRNA、泰泽氏菌的16SrRNA、空肠弯曲菌的flaA、肝螺杆菌的flaB和幽门螺杆菌的cagA基因序列与GenBank中细菌相应序列同源性高达100%,说明上述6种致病菌的16SrRNA、flaA、flaB和cagA基因已成功克隆。结论成功克隆了布鲁氏菌16SrRNA、支原体的16SrRNA、泰泽氏菌的16SrRNA、空肠弯曲菌的flaA、肝螺杆菌的flaB和幽门螺杆菌的cagA基因,为建立实时荧光定量PCR检测方法奠定了基础。     

乙型肝炎病毒基因变异、p16蛋白失活与肝癌的相关性研究

目的探讨乙型肝炎病毒（HBV）基因变异及肿瘤抑制基因p16蛋白失活与肝癌发生的关系。方法用基因芯片和核苷酸序列分析技术对114例HBV感染者（观察组）血清和43份肝组织标本中HBV DNA（前C区1814、1896、BCP区1762、1764位）进行分析,用流式细胞荧光染色法检测观察组和20例正常献血者（正常对照组）外周血白细胞中p16蛋白表达。结果观察组慢性重症乙型肝炎、肝硬化、肝癌患者血清HBV基因总突变率显著高于慢性乙型肝炎患者（P〈0．01）,肝硬化、肝癌肝组织HBV基因总突变率显著高于正常组织;正常对照组外周血自细胞中p16蛋白阳性率显著低于慢性乙型肝炎、肝硬化、肝癌患者,肝硬化、肝癌患者阳性率显著高于慢性乙型肝炎患者。结论HBV变异可能是肝癌发生的始动因子,而p16蛋白失活是肝癌发生的重要因素。     

慢性乙型肝炎患者幽门螺杆菌感染状况及其相关因素分析

目的探讨慢性乙型肝炎患者幽门螺杆菌（HP）感染状况。方法采用病例对照研究对502例慢性乙型肝炎患者的抗-HP-IgG和乙型肝炎病毒（HBV）DNA定量及分型进行检测。结果HP感染率在慢性乙型肝炎组（59．5％）、乙型肝炎肝硬化组（77．1％）及合并肝癌组（80．6％）均明显高于健康对照组（43．4％）,且随着病变程度的加重,HP感染率亦增加。HBVDNA阳性组的慢性乙型肝炎患者HP感染率高于HBVDNA阴性组（P〈0．05）和健康对照组（P〈0．001）,但不同病毒载量组之间比较差异无统计学意义。不同HBV基因型之间HP感染率无明显差异。肝硬化合并肝性脑病、消化性溃疡和消化道出血等并发症者HP感染率较高。结论慢性乙型肝炎患者幽门螺杆菌感染率明显增加,且随着病变程度的加重,HP感染率亦增加。乙型肝炎肝硬化患者并发症的发生可能与HP感染有关。     

贵阳地区幽门螺杆菌临床分离株中ureA、cagA、vacA、iceA基因的分布及分析

目的了解贵阳地区临床分离的幽门螺杆菌（Hp）的毒力基因ureA、cagA、vacA、iceA的分布特征,探讨不同毒力基因型与上消化道疾病的关系。方法用特异的16SrDNA聚合酶链反应进行临床分离Hp的菌种鉴定,对经过鉴定的152株幽门螺杆菌进行ureA、cagA、vacA、iceA基因及亚型的PCR检测。结果 ureA基因的检出率为100%（152/152）,vacA基因的检出率为100%（152/152）,vacA基因亚型以s1a-m2型为主,占76.3%（116/152）,cagA基因检出率为39.5%（60/152）,ieeA1基因检出率36.8%（56/152）,iceA2基因检出率为34.2%（52/152）,13.2%（20/152）的菌株iceA1和iceA2基因均阳性,不同基因型菌株在慢性胃炎和消化性溃疡中的检出率无统计学意义（P〉0.05）。结论贵阳地区幽门螺杆菌毒力基因vacA以s1a-m2型为主,cagA阴性比例高于cagA阳性,不同基因型菌株与消化性疾病间无明显相关性。     

Helicobacter infection in hepatocellular carcinoma tissue

AIM: To investigate whether Helicobacter species (Helicobacter spp.) could be detected in hepatocellular carcinoma (HCC) tissue. METHODS: Liver samples from 28 patients with hepatocellular carcinoma (HCC) diagnosed by histopa-thology were studied. Twenty-two patients with other liver diseases (5 with liver trauma, 7 with cavernous liver hemangioma, 6 with liver cyst and 4 with hepatolithiasis), 25 patients with gastric cancer, 15 with colonic cancer and 15 with myoma of uterus served as controls. Two piceces of biopsy were obtained from each patient. One was cultured for Helicobacter spp. and extraction of DNA, the other was prepared for scanning electron microscopy (SEM) and in situ hybridization. The samples were cultured on Columbia agar plates with microaerobic techniques. Helicobacter spp. in biopsy from the studied subjects was detected by polymerase chain reaction (PCR) with Helicobacter spp. 16S rRNA primers. Amplified products were identified by Southern hybridization and sequenced further. Besides, other genes (vacA, cagA) specific for Helicobacter pylori (H pylori) were also detected by PCR. Helicobacter spp. in biopsies was observed by SEM. Transmission electron microscopy (TEM) was performed to identify the cultured positive Helicobacter spp. The presence of Helicobacter spp. was detected by in situ hybridization to confirm the type of Helicobacter. RESULTS: The positive rate of Helicobacter cultured in HCC and gastric cancer tissue was 10.7% (3/28) and 24%(6/25), respectively. Helicobacter microorganisms were identified further by typical appearance on Gram staining, positive urease test and characteristic colony morphology on TEM. The bacterium was observed in adjacent hepatocytes of the two HCC samples by SEM. The number of cocci was greater than that of bacilli. The bacterium was also found in four gastric cancer samples. PCR showed that the positive rate of HCC and gastric cancer samples was 60.7% and 72% respectively, while the controls were negative (P<0.01). The PCR-amplified products were identified by Southern hybridization and sequenced. The homology to 16S rRNA of H pylori was 97.80%. The samples were verified by in situ hybridization for Helicobacter spp. 16S rRNA mRNA and proved to be H pylori positive. There was no statistical significance between HCC and gastric cancer (P>0.05), but the positive rate of HCC and controls had statistical significance (P<0.01). Only 3 HCC samples and 2 gastric cancer samples of the cagA genes were detected. None of the samples reacted with primers for vacA in the two groups. As for the genotype of H pylori, typeⅡhad preference over typeⅠ. CONCLUSION: Helicobacter infection exists in liver tissues of HCC patients. Helicobacter spp. infection is related with HCC, which needs further research.     

上海地区幽门螺杆菌cagA基因3’区和vacA基因的多态性分析及其临床意义

探讨上海地区人群中幽门螺杆菌（H．pylori）cagA基因3’区和vacA基因的多态性及其临床意义。方法：99株H．pylori菌株分离自17例慢性浅表性胃炎（CSG）、21例慢性萎缩性胃炎（CAG）、19例胃溃疡（GU）、23例十二指肠溃疡（DU）和19例胃癌（GC）患者。用聚合酶链反应（PCR）技术对H．pylori菌株的cagA基因3’区和vacA基因信号序列及中间区等位基因进行扩增和检测。结果：99株H．pylori菌株中84株（84．8％）cagA基因阳性,其3’区产物大小均约650bp,属A型。vacA基因信号序列仅检出sla型,见于从94．1％（16／17）的CSG、952％（20／21）的CAG、89．5％（17／19）的GU、87．00（20／23）的DU和89．5％（17／19）的GC患者中分离的菌株（P＝0．87）;中间区等位基因仅检出m2型,见于从70．6％（12／17）的CSG、71．4％（15／21）的CAG、63．20（12／19）的GU、73．9％（17／23）的DU和57．9％（11／19）的GC患者中分局的菌株（P＝0．72）。结论：上海地区人群中H．pylori菌株的cagA基因3’区相对保守;绝大多数vacA基因属sla／m2型。本研究结果不支持这些基因的多态性与H．pylori感染临床结局相关的观点。     

慢性乙型肝炎患者幽门螺杆菌感染的调查分析

目的探讨慢性乙型肝炎患者幽门螺杆菌(H.pylori)的感染情况及其临床意义。方法将167例慢性乙型肝炎患者分为肝炎组、肝硬化组、肝癌组,研究H.pylori感染状况与76例健康对照者的关系,并进一步分析H.pylori感染与肝功能、临床并发症的关系。结果慢性乙型肝炎患者H.pylori感染率为64.1%,明显高于健康对照组34.2%(P<0.01)。其中肝硬化组71.8%和肝癌组75.0%又高于肝炎组51.5%(P<0.05)。H.pylori阳性患者肝性脑病、上消化道出血及ALT水平高于H.pylori阴性患者(P<0.05),H.pylori阳性和H.pylori阴性患者的腹水并发症及TBIL差异无统计学意义(P>0.05)。结论慢性乙型肝炎患者H.pylori感染率显著增加,且H.pylori感染可能加重肝病病程。     

Helicobacter pylori and other Helicobacter species DNA in human bile samples from patients with various hepato-biliary diseases

AIM: To investigate the presence of Helicobacter species by nested PCR of 16S rRNA genes followed by the presence of Helicobacter pylori (H pylori) 16S rRNA, ureA, cagA genes in bile obtained at endoscopic retrograde cholangio-pancreatography (ERCP) from 60 Indian subjects. METHODS: Sixty bile samples were obtained from patients diagnosed with various hepato-biliary diseases and control subjects at ERCP. PCR analysis was carried out using primers for Helicobacter genus 16S rRNA gene and H pylori (16S rRNA, ureA and cagA) genes. Gastric H pylori status was also assessed from biopsies obtained at endoscopy from patients with various hepato-biliary diseases and controls. The control group mainly consisted of subjects with gastric disorders. Sequencing analysis was performed to confirm that PCR products with 16S rRNA and cagA primers were derived from H pylori. RESULTS No Helicobacters were grown in culture from the bile samples. Helicobacter DNA was detected in bile of 96.7% and 6.6% of groups I and II respectively. Ten from group I were positive for 16S rRNA and ureA and 9 were positive for cagA gene. In contrast of the 2 from the control, 1 amplified with 16S rRNA, ureA and cagA primers used. The sequences of the 16S rRNA genes and cagA were 99% similar to Helicobacter pylori. CONCLUSION: Helicobacters are associated with the pathogenesis of various hepato-biliary disorders.     

Helicobacter pylori in dental plaque and stomach of patients from Northern Brazil

AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR co...     

Direct determination of Helicobacter pylori vacA genotypes and cagA gene in gastric biopsies and relationship to gastrointestinal diseases

OBJECTIVE: Our aim was to detect Helicobacter pylori (H. pylori) from gastric biopsies of 248 patients using a novel, polymerase chain reaction (PCR)-based methodology, which simultaneously facilitates the determination of H. pylori vacA genotypes and cagA gene. METHODS: A simple methodology for sample preparation was established and PCR was performed with primer systems for the 16S rRNA, vacA, and cagA genes, thus circumventing the need to culture H. pylori and to extract DNA from biopsy samples. RESULTS: Infection with H. pylori was detected in 147 (59.3%) of 248 patients. The vacA signal sequence genotype s1 was present in 104 (81.3%) of 128 H. pylori-positive patients, and 24 (18.8%) patients had the genotype s2. The vacA middle region types m1 and m2 were detected in 46 (35.9%) and 79 (61.7%) patients, respectively. The combinations s1/m2 (43%) and s1/m1 (35.9%) were found more frequently than s2/m2 (18.8%). The cagA gene was detected in 75 (72.1%) of 104 H. pylori-positive biopsies with the vacA genotype s1. All 24 biopsies with the type s2 were cagA negative. Strains of the type vacA s1 were found in 97% of H. pylori-positive patients with peptic ulcer disease and were associated with the presence of the cagA gene, whereas 96% of the strains of the type vacA s2 were detected in patients who only had nonulcer dyspepsia. CONCLUSIONS: Using a novel PCR-based methodology, H. pylori 16S rRNA gene, vacA genotypes, and cagA gene can now be rapidly detected directly in gastric biopsies with high accuracy. These data demonstrate that infection with H. pylori strains of the vacA s1 genotype and the cagA gene are more likely to result in peptic ulcer disease. Determination of vacA genotypes and cagA gene may contribute to the potential clinical identification of patients at different levels of risk.     

不同幽门螺杆菌培养滤液对胃上皮细胞端粒酶活性的影响

目的　分析不同幽门螺杆菌 (H .pylori)培养滤液对胃上皮细胞端粒酶活性的影响。 方法　分别以来自胃癌患者和来自慢性浅表性胃炎患者的cagA+ vacAs1a/m2和来自慢性浅表性胃炎患者的cagA+ vacAs1b/m2、cagA-vacAs1a/m2的H .pylori培养滤液与胃上皮细胞共孵育 ,然后撤除刺激物继续培养 ,观察不同时间的DNA合成速率和端粒酶活性。 结果　cagA+ vacAs1a/m2和cagA+ vacAs1b/m2Hp培养滤液与胃上皮细胞共孵育 6h ,诱导了胃上皮细胞端粒酶活性表达上调 ,DNA合成速率增加 ,cagA+ vacAs1a/m2的作用明显强于cagA+ vacAs1b/m2 ,撤除刺激物继续培养 2 4h后 ,其改变得以逆转 ;cagA-vacAs1a/m2H .pylori培养滤液与胃上皮细胞共孵育 ,其端粒酶活性和DNA合成速率无明显改变。 结论　不同H .pylori培养滤液对胃上皮细胞端粒酶活性的影响各异 ,cagA+ vacAs1a/m2Hp的毒性产物显著地诱导了胃上皮细胞端粒酶活性表达上调     

vacA genotypes of Helicobacter pylori in relation to cagA status and clinical outcomes in Iranian populations

Mosaicism in vacA alleles with two distinct families of vacA signal sequences (s1 and s2) and two distinct families of middle region alleles (m1 and m2) has been reported. Research suggests that the vacA s1 genotype is closely associated with duodenal ulcer disease and with high cytotoxin production. The aims of this study were to evaluate the role of vacA genotyping with respect to gastric inflammation and injury, and clinical presentation in Iranian populations. Genomic DNA of biopsy specimens from patients with gastritis, peptic ulcer disease (PUD), or gastric cancer (GC) were characterized based on ureC (glmM), cagA, and vacA genotyping by using polymerase chain reaction. Of 167 patients including 33 with PUDs, 129 with non-ulcer dyspepsia (NUD), and 5 with GC, 96 (57.5%) cases were infected by Helicobacter pylori. Among these patients, H. pylori were isolated from 19 (57.7%) PUD patients, 74 (68.7%) NUD patients, and 3 (60%) GC patients. The cagA was detected in 76% of H. pylori-positive cases. The vacA s1-m2 genotype was the most prevalent in 7/19 PUD (37%) and 30/74 NUD (40.5%) patients with H. pylori infection. The prevalence of vacA s2-m1 (8%) was high in Iranian isolates. A significant association was not found between H. pylori genotypes and clinical outcomes. The vacA genotypes and cagA status were not useful markers for gastroduodenal diseases in Tehran, Iran.     

Prevalence of Helicobacter pylori vacA, cagA, cagE, iceA and babA2 genotypes in Thai dyspeptic patients.

OBJECTIVES: To investigate the prevalence of the vacA, cagA, cagE, iceA, and babA2 genotypes in Helicobacter pylori strains isolated from Thai dyspeptic patients, and to determine whether any correlation exists between these genotypes and clinical manifestations. METHODS: Helicobacter pylori was examined in 112 patients (62 with non-ulcer dyspepsia (gastritis), 34 with peptic ulcer disease, and 16 with gastric cancer (GCA)), detected by culture or direct detection from gastric biopsies. Allelic variants of the vacA, cagA, cagE, iceA, and babA2 genotypes were identified by using the polymerase chain reaction. RESULTS: The positive rates for the vacAs1, vacAs2, cagA, cagE, iceA1, iceA2, and babA2 genes in H. pylori of dyspeptic patients were 100%, 0%, 98.2%, 88.4%, 45.5%, 33.1%, and 92%, respectively. The allelic variant vacAs1m1 was more prevalent (58%) than vacAs1m2 (42%). The cagA and cagE genes were commonly found together (87.5%). The most predominant genotypes were vacAs1m1, cagA, cagE, iceA1, and babA2. The various genes alone or in combination had no statistically significant association with the clinical outcomes (p>0.05). CONCLUSION: Neither single gene nor combination of vacA, cagA, cagE, iceA, and babA2 genes was significantly helpful in predicting the clinical outcome of H. pylori infection in Thai patients. The high prevalence of these genes in H. pylori isolated from Thai patient groups suggests that H. pylori strains are geographically dependent.