Epidemiology And Drug Resistance Mechanism Of Multicenter Carbapenem-Resistant Enterobacteriaceae In Eastern Inner Mongolia

Objective:To study the drug resistance,infection risk factors,molecular epidemiology and drug resistance mechanism of Carbapenem-resistant Enterobacteriaceae(CRE)in multiple centers.Methods:We Collected 182 CREs from 5 sentinel hospitals in eastern Inner Mongolia from 2014 to 2019,and identified them with VITEK MS mass spectrometer.KB paper diffusion method and E test strip were used to determine a total of 155 strains after drug sensitivity.Case-control study to analyze the risk factors of CRE infection;Carba NP test and modified carbapenem inactivation test to detect carbapenemase produced by the strain,polymerase chain reaction qPCR to detect carbapenemase gene,and positive qPCR Product sequence to determine strain genotype;MALDI-TOF MS analysis of CRE homology.Results:The drugs with high CRE sensitivity:minocycline and amikacin have an overall sensitivity rate of 53.06%and 52.25%,besides,the remaining clinical commonly used antibacterial drugs are highly resistant.Age≥60 years,use of aminoglycosides,β-lactam antibiotics and invasive procedures are the risk factors for CRE infection in eastern Inner Mongolia.Carba NP test and modified carbapenem inactivation test detected carbapenemase positive rate is 64.3%,carbapenemase gene test positive rate is 78.6%,the mainly genotype of carbapenemase is carbapen NDM(87.9%)And OXA(66.7%),VIM-1 and KPC-2 are not detected.Six strains of Klebsiella pneumoniae carried three resistance genes of IMP,NDM and OXA.MALDI-TOF MS divided 85 strains of Klebsiella pneumoniae into type 4 and 80 strains of type Ⅰ;47 strains of Enterobacter cloacae were divided into type 3 and 45 strains of type Ⅰ;16 strains of Escherichia coli were divided into type 3 and type Ⅰ 13 strains.Conclusion:The collected 155 strains of CRE are highly resistant to most commonly used antibacterials in clinical practice and have multiple drug resistance,but the drug resistance rate is lower than the national level.Clarified risk factors for CRE infection in the area.It is speculated that carbapenemase is the main drug resistance mechanism of CRE infection in this area.In particular,In particular,we found that six strains of Klebsiella pneumoniae carry three resistance genes of IMP,NDM and OXA,suggesting that relevant departments should strengthen the management of CRE infection,improve surveillance and prevention Strength.MALDI-TOF MS analysis showed that Klebsiella pneumoniae,Enterobacter cloacae,and Escherichia coli isolates were mainly of one type in eastern Inner Mongolia,and clonal transmission was observed,but no outbreak was found.MALDI-TOF MS analysis of drug-resistant strain homology has the characteristics of convenient operation,time-saving,and low cost.Laboratories should make full use of this technology to investigate the transmission route of drug-resistant bacteria as early as possible to avoid outbreaks of nosocomial events.