幽门螺杆菌的耐药性分析

目的:分析幽门螺杆菌(Hp)菌株对阿莫西林、克拉霉素、甲硝唑、呋喃唑酮的耐药情况,并探讨Hp对克拉霉素耐药与23S rRNA基因点突变的关系.方法:分离培养Hp,药敏纸片法进行药敏实验,按酚-氯仿法提取Hp的DNA,PCR方法扩增23S rRNA基因中的片段,用限制性片段长度多态性(PCR-RFLP)检测克拉霉素耐药菌株的点突变.结果:Hp菌株对阿莫西林、克拉霉素、甲硝唑、呋喃唑酮的耐药率分别为9.3%、18.6%、53.5%、0%;8个克拉霉素耐药的Hp菌株有7个存在23S rRNA基因的A2143G点突变,进行PCR-RFLP的29个敏感菌株均无23S rRNA的点突变.结论:Hp菌株对甲硝唑耐药率高,对克拉霉素、阿莫西林和呋喃唑酮敏感;23S rRNA基因A2143G点突变与Hp对克拉霉素的耐药相关.

Drug-resistance of Helicobacter pylori

Aim: To analyze the prevalence of Helicobacter pylori(Hp) strains resistant to amoxiclillin,clarithromycin,metronidazole and furaltadone and the relation of genetic mutation with clarithromycin resistance.Methods:Hp strains were isolated from gastric mucosa biopsies of patients with peptic ulcer or gastritis. Resistance of the isolates to clarithromycin was determined using diffusion test. DNAs of the bacteria were extracted with the phenol-chloroform method.Mutations in clarithromycin resistant strains were identified by PCR-RFLP.Results: The prevalences of Hp strains resistant to amoxiclillin,clarithromycin, metronidazole and furaltadone were 9.3%, 18.6%, 53.5% and 0%, respectively.Seven out of 8 clarithromycin-resistant strains had A2143G point mutation in 23S rRNA gene, and none of the twenty-nine susceptible strains had the A2142G or A2143G mutation. Conclusion: The prevalence of Hp to metronidazole is high, which is susceptible to clarithromycin, amoxiclillin and furaltadone; mutations in 23S rRNA are associated with clarithromycin resistance in Hp.