摘要目的 研究北京地区5家教学医院临床分离的亚胺培南耐药铜绿假单胞菌(IRPA)对碳青霉烯类抗菌药物耐药的分子机制.方法 收集2004年6月-2005年12月北京地区5家教学医院临床分离的非重复性213株IRPA,采用琼脂稀释法测定美罗培南、亚胺培南等抗菌药物对这些菌株的MIC值;采用纸片法初筛产金属酶菌株;对金属酶IMP-、VIM-基因以及孔道蛋白OprD2基因进行PCR及序列分析.结果 5家教学医院分离的213株IRPA中84株存在孔道蛋白OprD2缺失,其中有6株还同时产IMP-1型金属酶.另有13株IRPA单独产IMP-1型金属酶,2株单独产VIM-2型金属酶.结论 孔道蛋白OprD2缺失、产金属酶是北京地区铜绿假单胞菌(PA)对碳青霉烯类抗菌药物耐药的部分机制.

abstractsObjective To investigate the molecular mechanism of resistance to carbapenems in Pseudomonas aeruginasa from 5 teaching hospitals in Beijing. Methods A total of 213 non-duplicate imipenem-resistant Pseudomonas aernginosa (IRPA) isolates were collected from 5 hospitals in Beijing from June 2004 to December 2005. The minimal inhibitory concentrations (MICs) of meropenem, imipenem and others antibiotics were determined by agar dilution method. Disk diffusion test was used for screening metalloenzymes. The bla IMP,bla VIM and OprD2 genes were amplified by PCR and only sequenced. Results Out of 213 isolates, OprD2 loss was detected in 84 isolates and IMP-1 enzyme was detected in 6 isolates simultaneously. Thirteen IRPAs only produced IMP-1 and 2 isolates only produced VIM-2. Conclusion OprD2 loss and metallo-β-lactamuse production are the parts of the mechanisms of resistance to carbapenems in Pseudomonas aeruginosa in Beijing.