碳青霉烯类异质性耐药铜绿假单胞菌的耐药机制研究

摘要：目的 筛选铜绿假单胞菌临床分离株的碳青霉烯类异质性耐药菌株，并分析相关机制。方法 采用E-test纸条法、群体分析法(PAP)法对30株铜绿假单胞菌临床分离株进行亚胺培南异质性耐药的初筛和复筛、肉汤微量稀释法测定异质性耐药菌株对亚胺培南及其他药物的MIC值、全基因组测序分析碳青霉烯类异质性耐药菌株的可能耐药机制。结果 通过E-test纸条法和PAP法鉴别筛选出8株亚胺培南异质性耐药铜绿假单胞菌，检测发现异质性耐药菌株对多黏菌素B、头孢他啶、美罗培南耐药率较高，对环丙沙星等更敏感。全基因组测序分析发现碳青霉烯类异质性耐药铜绿假单胞菌无可确证的基因突变，但可能与延伸因子P基因有关。

Resistance mechanism study of carbapenem heteroresistant Pseudomonas aeruginosa

Abstract Objective To identify and screen the heteroresistant strains in Pseudomonas aeruginosa clinicalisolates, and to analyze the related mechanisms. Methods The E-test and the PAP method were used for primary andre-screening of the imipenem heteroresistant ones from 30 Pseudomonas aeruginosa clinical isolates. MIC values ofimipenem and other drugs against heteroresistant Pseudomonas aeruginosa were determined by broth microdilutionmethod. The resistant mechanisms of the heteroresistant strains were analyzed by whole-genome sequencing. Result8 imipenem heteroresistant strains were selected by E-test and PAP method. The heteroresistant strains showedrelatively high resistance rates to polymyxin B, ceftazidime, meropenem, but seemed to be more susceptible tociprofloxacin, etc. Whole-genome sequencing analysis showed that there is no confirmed gene mutations responsiblefor Pseudomonas aeruginosa heteroresistance, but it may be related to the elongation factor P