河西走廊地区幽门螺杆菌vacAi区分型及与疾病相关性探讨

Association of vacA intermediate region genotypes and Helicobacter pylori-related diseases in the Hexi Corridor

目的探讨河西走廊胃癌高发区患者幽门螺杆菌(Helicobacter pylori,Hp)vacA i区基因型的分布,以期为当地Hp流行病学研究和疫苗研制提供参考。方法复苏和纯培养从河西走廊地域医院收集并分离到的Hp,设计va-cA i1和i2引物,PCR扩增vacA基因i区并鉴定,分析Hp菌株中vacA i区的基因型以及不同基因型与患者临床病理类型、性别和年龄的关系。结果从55名患者中分离到的61株Hp vacA i1和i2型的构成比分别为86.89%(53/61)和13.11%(8/61)。vacA i1型在60～岁、41～岁年龄组,同性别以及相同病理类型患者中的构成比均显著高于vacA i2(P<0.05);同型的vacA i1和i2在不同性别、60岁以下各年龄间和病理类型患者间的构成比差异无统计学意义(P>0.05)。60岁以上患者中Hp vacA i2型构成比显著高于60岁及以下各年龄段人群(P<0.05)。结论河西走廊地区流行的Hp菌株vacA基因i区均阳性,以i1型为主。vacA i区基因型分布与患者的疾病类型、性别等无关,Hp vacA i2型构成比呈现随年龄增高而上升的趋势。

Objective To examine the distribution of intermediate （i） region genotypes of the vacA gene of Helicobacter pylori in patients in the Hexi Corridor, where gastric cancer is highly prevalent, in order to study H. pylori epidemio logically and to develop vaccines. Methods H. pylori isolated from regional hospitals in the Hexi Corridor was collected and cultured. Primers for vacA il and i2 genotypes were designed. PCR was used to amplify and identify the vacA i region genotype. The relationship between the H. pylori vacA i region genotype and the patienfs clinical pathology, gender, and age was analyzed statistically. Results Of 61 Strains of H. pylori isolated from 55 patients, 86.89% （53/61） had the vacA il genotype while 13.11% （8/61） had the vacA i2 genotype. The rate of infection with the vacA il geno- type was significantly higher than that with the i2 genotype for patients age 60 and over and those age 41 and over. The vacA i2 genotype was markedly more prevalent in patients of the same sex and with the same clinical pathology （P〈0. 05）. There were no significant differences in terms of sex groups, age （under 60） or clinical pathology for patients with the same vacA il or i2 genotype （P〈0.05）. The rate of infection with the vac＇A i2 genotype was significantly higher for patients age 60 and over than for those under age 60 （P〈0.05）. Conclusion H. pylori from the Hexi Corridor was positive for the vacA i region, and il was the main genotype. The distribution of the vacA i region genotype was not associated with pathology or age. Infection with the vacA i2 region genotype tended to increase with age.