琼脂稀释法检测5种抗菌药物对幽门螺杆菌的体外抑制效应

Detection of in Vitro Inhibitory Effect of Five Antibiotics on Helicobacter Pylori by Agar Dilution Method

目的:探讨临床常用的5种抗菌药物对幽门螺杆菌(Hp)的体外抑制效应,旨在为临床根除Hp提供理论参考。方法:琼脂稀释法测定单药及联合用药对110株临床分离的Hp的最小抑菌浓度(MIC)和联合抑菌分数(FIC)。结果:110株Hp对5种抗菌药物的耐药率,左氧氟沙星为76.4%、克拉霉素为51.8%、替硝唑为20.9%、阿莫西林为8.2%、左奥硝唑为2.7%。5种抗菌药物的二联用药对Hp的抑制效应为:阿莫西林联合克拉霉素/左奥硝唑的协同抑制效应最强,替硝唑联合阿莫西林/左奥硝唑、左氧氟沙星联合阿莫西林/左奥硝唑具有协同抑制效应,克拉霉素联合左奥硝唑具有累加抑菌效应。结论:Hp对左氧氟沙星有较高的耐药性,对克拉霉素和替硝唑有一定的耐药性,对阿莫西林和左奥硝唑较敏感;阿莫西林联合克拉霉素/左奥硝唑对Hp的协同抑制效应最强。对根除Hp的治疗应在药物敏感性试验检测结果下选择性地应用抗菌药物。

OBJECTIVE：To investigate the in vitro inhibitory effect of five antibiotics on helicobacter pylori （H. pylori） by agar dilution method so as to provide theoretical reference for clinical H. pylori eradication. METHODS： The minimum inhibitory concentration （ MIC ） and fractional inhibitory concentration （FIC） of antibiotics used either alone or in combination against 110 H. pylori strains separated clinically were detected by agar dilution method. RESULTS： The resistance rates of 110 H. pylori strains to levofloxacin, clarithromycin, tinidazole, amoxicillin and levornidazole were 76. 4%, 51.8%, 20. 9%, 8.2%, and 2.7%, respectively. The antibiotic combination of amoxicillin plus clarithromycin/ levornidazole showed the most potent synergistic inhibitory effect against H. pylori, the combination of tinidazole plus amoxicillin/ levornidazole and the combination of levofloxacin and amoxicillin/Levornidazole had synergistic inhibitory effect, and the combination of clarithromycin plus Levornidazole had the cumulative antibacterial effect. CONCLUSION： H. pylori strains have high resistance to levofloxacin and certain resistance to clarithromycin and tinidazole, yet which were sensitive to amoxicillin and levornidazole; the synergistic inhibitory effect of combination of amoxicillin and clarithromycin/ levornidazole was the strongest. The antibiotics against H. pylori eradication should be used selectively with drug susceptibility test as guidance.