Analysisof drug resistance mechanism and characteristics of carbon-resistant pseudomonas aeruginosa / 现代医院

ABSTRACT

Objective To explore the drug resistance mechanism and characteristics of carbopenem-resistant pseudo-monas aeruginosa(CRPA)in our hospital.Methods BD phoenix 100 automatic bacterial identification and drug sensitivity an-alyzer was used to identify and detect the drug sensitivity of the strains.The minimum inhibitory concentration(MIC)of ceftazi-dime/acibactam was detected by micro broth dilution method.The modified carbapenem inactivation method(mCIM)and colloi-dal gold immunochromatography were used to detect the carbapenemase phenotype of the strains.The whole genome sequencing was used to detect the carbapenemase resistance gene and ST typing of the screened positive strains.Results A total of 22 strains of clinically isolated CRPA were collected,of which the antibacterial drugs with the lowest resistance rate were ceftidine/avibatan(22.7% ),followed by gentamicin and amikacin(27.3% ),pyracillin/tazobactam(59.09% ),cefuroxime(63.6% ).Ceftazide and aminotransferrane(77.27% ),ciprofloxacin(86.36% ),levofloxacin(95.45% ).There are a total of 5 strains(22.7% )of carbapenems in 22 CRPA by phenotypic detection.The whole genome sequencing results show that 4 strains of ST549 CRPA carry metal β-lactamase IMP-45 and serine β-lactamase OXA-1,OXA-50,one strain is ST245 CRPA carries metal β-lactamase NDM-1,that is,all five CRPA strains produce metal β-lactamase.Conclusion The resistance rate of CRPA to ceftazidime/avibactam is low in our hospital.Carbapenemase-producing is not the main mechanism of CRPA resistance to car-bapenems,while metal β-Lactamase-producing is the main mechanism of CRPA resistance to ceftazidime avibactam.