淮南地区幽门螺杆菌感染个体菌株基因多态性与感染结局的影响

目的:探讨淮南地区幽门螺杆菌感染个体菌株基因多态性及其与感染结局的影响。方法:选取125例幽门螺杆菌(H.pylori,HP)感染的慢性胃炎、消化性溃疡患者,常规获取胃窦、胃体部粘膜,进行HP分离、培养,提取HP基因组DNA,采用随机扩增多态性DNA(RAPD)指纹分析法检测菌株基因多态性;125例患者均给予质子泵抑制、H2受体拮抗剂、铋剂为基础的三联或四联疗法治疗,治疗后4~6周进行14C-尿素呼气试验评估Hp根除情况;获取HP根除失败患者的胃窦、胃体黏膜进行HP分离、培养、鉴定,并采用RAPD指纹分析法检测菌株来源,评估HP基因多态性对治疗结局的影响。结果:cagA、iceA1、iceA2、vacAs1、vacAm1、babA2阳性率分别为92.80%、36.00%、93.60%、93.60%、29.50%、53.50%,cagA、iceA2、vacAs阳性率均高于其他基因类型阳性率(P0.05或P0.01),其他基因类型阳性率比较差异无统计学意义(P0.05)。经治疗后HP根除率为86.4%(107/125),14.4%(18/125)根除失败;18例根除失败患者中,15例患者治疗前后的菌株具有相同的指纹图谱,证实为原菌株复发,其中cagA、iceA1、iceA2、vacAs1、vacAm1、babA2阳性率分别为93.33%、13.33%、86.67%、93.33%、6.67%、20.00%,cagA、iceA2、vacAs阳性率均高于其他基因类型阳性率(P0.05或P0.01)。结论:cagA+、vacAs+、iceA2+为淮南地区HP感染的优势基因型,该基因型易导致HP根除失败;未发现babA2与HP感染结局存在相关性。

Gene Polymorphism of Individual Strains of Helicobacter pylori in Huainan and Infection Outcomes

Objective:To investigate the gene polymorphism and infection outcome of individual strains of Helicobacter pylori infection in Huainan region.Methods:Helicobacter pylori was isolated from the gastric antrum, gastric mucosa of 125 patients with HP infected chronic gastritis or peptic ulcer and cultured. Then HP DNA was extracted. Random amplified normality DNA (RAPD) fingerprinting assay was used to test the strain polymorphism. Then the 125 patients were treated with proton pump inhibitors, H2 receptor antagonists, bismuth-based triple or quadruple therapy. After treatment for 4 to 6 weeks, 14C-urea breath test was used for Hp eradication assessment. Then the HP were isolated from gastric antrum, gastric mucosa of patients with HP eradication failure, cultured and identified, and analyzed by RAPD fingerprinting assay to assess the effects of HP genetic polymorphism on treatment outcome.Results:The positive rates of cagA, iceA1, iceA2, vacAs1, vacAm1 and babA2 were respectively 92.80%, 36.00%, 93.60%, 93.60%, 29.50%and 53.50%. The positive rates of cagA, iceA2, vacAs were significantly higher than other types of gene-positive rate (P<0.05 or P<0.01), and other types of gene positive rates had no significant difference (P>0.05). After treatment, 86.4% (107/125) had HP eradication, and 14.4% (18 / 125 ) failed. Among the18 patients with eradication failure, 15 had the same strain fingerprints before and after treatment, and were confirmed as the original strain recurrence. Their positive rates of cagA, iceA1, iceA2, vacAs1, vacAm1, babA2 were respectively 93.33%, 13.33%, 86.67%, 93.33%, 6.67%, 20.00%; the rates of cagA, iceA2, vacAs were significantly higher than other types of genes positive rate (P<0.05 or P<0.01).Conclusion:cagA +, vacAs +, iceA2 + were the dominant genotype of HP infection in Huainan region. These genotype easily lead to HP eradication failure. babA2 was found having no correlation with the presence of HP infection outcome.