Resistance Mechanisms Of Imipenem In Clinical Isolates Pseudomonas Aeruginosa

[Objective] Pseudomonas aeruginosa is a clinical Gram-negative pathogen that causes a wide range of opportunistic infections and the nosocomial outbreaks.This experiment in order to study the resistance mechanisms of imipenem in clinical isolates Pseudomonas aeruginosa in Chengdu.[ Methods ] The MICs to imipenem were detectde by an agar dilution metheod;PCR method and SDS—PAGE profile were used to detect the losing of OprD₂ in resistance strains;Using imipenem Mercapt-oacetic acid and EDTA Double-Disk synergy test to evaluate producing Metallo- β -lactamase bacteria in resistance strains; Using CCCP to inhib-itate the efflux pump;The levels of mRNA expression of OprM and OprN in clinical PA was determined by RT-PCR;[Results] In 62 clinical isolate strains, the resistance rate to imipenem was 45.16%;eleven imipenem resistance strains have the outer membrane protein losing; Only one resistance strain produced Metallo- β -lactamase; Efflux pump inhibitors CCCP can reduce MICs of four IMP- resistance strains;The levels of mRNA expression of OprM in resistant strains are higher than those in susceptible ones.[ Conclusions ] The study indicated that the resistance rate to...