喹诺酮类药物对耐药肺炎克雷伯杆菌的体外抗菌活性分析

Analysis of antibacterial activity of quinolone-resistance Klebsiella pneumoniae in vitro

目的:了解耐喹诺酮类肺炎克雷伯杆菌的体外抗菌活性及CCCP对喹诺酮类药物体外抗菌活性的影响。方法:从99株肺炎克雷伯杆菌临床分离株中选取对环丙沙星耐药(M IC≥4μg/m l)菌株14株。采用琼脂二倍稀释法测定抗菌药的最低抑菌浓度(M IC),同时测CCCP对喹诺酮类药物M IC的影响。结果:14株肺炎克雷伯杆菌对5种喹诺酮类药物无一株敏感,且表现出较高水平的耐药。对其它抗生素的耐药率由高到低依次是氨苄西林、哌拉西林、氯霉素、庆大霉素、氨曲南、阿米卡星、头孢噻肟和头孢吡肟。亚胺培南未发现有耐药株。喹诺酮类药物与CCCP合用后,在部分菌中的M IC中出现了明显的降低。结论:耐喹诺酮类肺炎克雷伯杆菌对喹诺酮类呈交叉耐药,且呈较高水平耐药;CCCP可以明显提高部分喹诺酮类药物对肺炎克雷伯杆菌的体外抗菌活性;亚胺培南、第三代头孢菌素、氨曲南和阿米卡星对耐喹诺酮肺炎克雷伯杆菌仍有一定作用。

Objective： To study the antibacterial activity of quinolone-resistant Klebsiella pneumoniae in vitro and the affect of carbonyl cyanide m-chlorophenylhydrazone（CCCP）. Methods： 14 strains quinolone-resistant were screened from 99 Klebsiella pneumoniae clinical isolates（ MIC≥4μg/ml to clprofloxacin）. Minimum inhibitory concentrations （MIC） of antibactefials against K. Pneumoniae were assayed by two-fold agar dilution method and MICs of quinolone with CCCP were determined simultaneously. Results： None of the 14 strains isolates were susceptible to the quindones and high level resistance was observed. The other antibiohcs ,by the resistant frequentcy from high to low was ampicillin, piperacillin, chloramphenicol, gentamycin, aztreonam, amikacin, cefotaxime and cefepime. No resistant strain was found to imipenem. Compared with single quinolone, MICs of some strains decreased 4 times or more when the quinolones used with CCCP. Conclusion： To quinolone-resistant Klebsiella pneumoniae , there are cross-resistance to quinolones , and the resistance is high. CCCP can increase antibacterial activity of quinolone distinctly. To the treatment of quinolone-resistance K. pneumoniae, imipenem or the 3rd generation cephalosporins combined with aztreonam or amikacin is the perfect choice.