Risk Factors Analysis Of Bloodstream Infection Caused By Colonized Carbapenem-resistant Enterobacteriaceae

Objective: To study the clinical distribution characteristics of Carbapenem-resistant Enterobacteriaceae(CRE)active screening positive patients and risk factors for colonization to bloodstream infection,to provide a theoretical basis for hospital infection prevention and control and rational use of clinical antibacterial drugs.Methods: From January 2019 to December 2021,active CRE screening was performed on high-risk susceptible individuals hospitalized in Zhejiang Provincial People’s Hospital.A total of 198 CRE screening-positive patients were divided into bloodstream infection group(37 cases)and non-bloodstream infection group(161 cases)according to the occurrence of bloodstream infection.The baseline characteristics and clinical data of the two groups were collected,the clinical distribution characteristics of CRE screening positive patients were analyzed,the drug-resistant genotypes of some CRE bloodstream infection strains were identified by whole-genome bacterial sequencing,and the risk factors of CRE colonization to bloodstream infection were analyzed by multi-factor logistic regression.Results: Zhejiang Provincial People’s Hospital sent a total of 2265 stool and anal swab screening specimens from January 2019 to December 2021,with 198 positive CRE screening specimens and a CRE detection rate of 8.74%(198/2265).These included 167 strains of Klebsiella pneumoniae(84.34%),15 strains of Escherichia coli(7.58%),8strains of Aspergillus chimaera(4.04%),3 strains of Enterobacter aerogenes(1.52%),and 5 strains of Enterobacter cloacae(2.52%).The main distribution of positive patients were 92 cases(46.46%)in Intensive care unit(ICU),40 cases(20.20%)in Hematology,15 cases(7.58%)each in Emergency Medicine and Infectious Diseases,12 cases(6.06%)in Rehabilitation Medicine,and 6 cases(3.04%)in Family Medicine.The resistance rates to common clinical antibiotics,penicillins,cephalosporins and quinolones were above 94%,while the resistance rates to tigecycline and ceftazidime/avibactam were relatively low,20.20% and 27.27%,respectively.Whole-genome bacterial sequencing of 12 CRE bloodstream infection samples showed that two drug resistance genes were detected,Klebsiella pneumoniae carbapenemase(KPC)(91.67%)and OXA-48(8.33%).Multifactorial logistic regression analysis showed that history of carbapenem antibiotic exposure(OR=3.715,95% CI: 1.003 to13.761,P<0.05),glucocorticoid use 30 days before infection(OR=3.073,95% CI: 1.198 to 7.698,P<0.05),neutrophil deficiency(OR= 9.258,95% CI: 2.894 to 29.614,P <0.01)were independent risk factors for CRE colonization to bloodstream infection.Conclusion: 1.The intestinal colonization rate of CRE in patients with positive active screening was 8.74%,with Carbapenem-resistant Klebsiella pneumoniae(CRKP)being the most common,mainly in key departments such as ICU and hematology.2.The main resistance genes of CRE bloodstream infection were KPC.3.History of carbapenemase antibiotic exposure,glucocorticoid use within 30 days,and neutrophil deficiency are independent risk factors for CRE colonization to bloodstream infection.