Abstract:Objective To analyze the clinical infection characteristics and resistance mechanisms of carbapenem-resistant Enterobacterales (CRE), provide reference for clinical prevention and treatment of CRE infection. Methods Clinically isolated CRE strains and patients information in a tertiary first-class hospital from July 2021 to June 2022 were collected. Antimicrobial resistance genes were detected by polymerase chain reaction. Induced antimicrobial resistance of mcr-9 positive strains was detected by inducing test. Results A total of 167 CRE strains were collected, mainly Klebsiella pneumoniae (38.9%) and Enterobacter cloacae (35.3%). CRE strains demonstrated multiple drug resistance phenotype, with 3 strains (1.8%) exhibiting polymyxin B resistance. Most CRE strains harboured blaNDM (52.1%, n=87) and blaKPC (34.7%, n=58). Patients with CRE infection were divided into NDM group and KPC group according to carbapenemase. Univariate analysis showed that in terms of influencing factors as stay in ICU ≥7 days, endotracheal intubation, and use of carbapenems before infection, KPC group was higher than NDM group, however, curing rate was lower than NDM group (P < 0.05). Multivariate logistic regression analysis showed that gastric intubation, pulmonary diseases and malignant tumor were independent influencing factors for the prognosis of patients with CRE infection of different carbapenemase genes (P < 0.05). Polymyxin B resistant strains all carried mgrB point mutation. 7 (4.2%) CRE strains harboured mcr-9, most of which also harboured blaNDM. MIC values of 4 mcr-9 positive CRE strains after polymyxin B induction were higher than those before induction. Conclusion CRE in this area mainly harbour blaNDM and blaKPC, and a few also harbour mcr-9 and blaNDM, showing multiple drug resistance. Clinical prevention and control should be strengthened to prevent its clinical transmission.