泵抑制剂对耐喹诺酮类铜绿假单胞菌临床株作用的研究

Study on reducing effect on clinical isolated quinolone resistance of Pseudomonas aeruginosa using four kinds of pump inhibitors

目的 了解四种泵抑制剂对喹诺酮类耐药铜绿假单胞菌株耐药水平的降低作用与耐药决定区基因突变及耐药表型的关系。方法 采用羰基氰氯苯腙 (CCCP)、利舍平、维拉帕米及奥美拉唑以琼脂稀释法分别加入喹诺酮耐药的菌株中 ,与喹诺酮类抗生素共同作用 ,并同时测定其最低抑菌浓度 (MIC)的变化。对部分耐药株 Gyr A和 Par C区进行 PCR- RFL P分析 ,并行 DNA测序观察突变情况。结果 四种泵抑制剂中CCCP能极大的降低 MIC的值。利舍平也可部分减低 MIC的值 ,但维拉帕米及奥美拉唑作用轻微。高度耐药株存在 gyr A和 par C的突变。结论 寻找理想的泵抑制剂可降低铜绿假单胞菌的耐药水平。

Objective To evaluate reducing effect on quinolone resistance of P.aeruginosa using four kinds of pump inhibitors and to study the relationship of quinolone resistance-determining region (QRDR) mutation with (and) pump efflux. Methods Minimum inhibitory concentrations (MICs) were measured with or without four kinds of pump inhibitors, including carbonyl cyamide-3-chlorophenylhydrazone (CCCP), respine (R), verapamil (V) and operamazine (O). PCR-RELF and sequencing approaches were used to detect the mutation of gyrA and parC. Results Of four pump efflux inhibitors,CCCP can significantly reduce MIC; while respine can also partly decrease MIC, but verapamil and operamazine play a minor role in changing MICs. There are mutations of gyrA and parC in the strains with high level of resistance. Conclusion Most of pump inhibitors used have good properties in reversing resistance of P.aeruginosa.