Drug Resistance And Risk Factors Of Bloodstream Infections Caused By Extended-spectrum ?-lactamases-producing Escherichia Coli

ObjectiveExtended-spectrum ?-lactamases-producing Escherichia coli(ESBLs-E.coli)is the most common pathogens of bloodstream infections in multi-drug resistant Enterobacteriaceae,and inadequate initial treatment increases patients' case fatality rates and treatment cost.Through analysis of the clinical data of hospitalized patients who were diagnosed with bloodstream infections caused by E.coli,the thesis aims to explore drug resistance and risk factors of ESBLs-E.coli,thus to provide basis for guiding rational application of antibacterial drugs in clinical practice and effectively preventing and controlling bloodstream infections caused by E.coli.MethodsA single center,retrospective study was undertaken in this research.The infectious strains of 368 patients diagnosed with bloodstream infections caused by E.coli from May 2013 to May 2017 in the First Affiliated Hospital of Soochow University were collected as research objects,which were divided into ESBLs-producing group and non-ESBLs-producing group.The drug resistance of E.coli was analysed.Risk factors of patients with bloodstream infections caused by ESBLs-E.coli were explored by the univariate analysis and multivariate Logistic regression analysis.ResultsOf the 368 patients diagnosed with bloodstream infections caused by E.coli during the research period,255(69.3%)were ESBLs-producing strains.The drug resistance rates of ESBLs-producing group to penicillin,second and third generation cephalosporin(except ceftazidime)were over 90%.The resistance rate to ampicillin was the highest(69.1%)in the strains of non-ESBLs-producing group.And both groups had the lowest resistance to imipenem(<10%).Univariate analysis indicated that ESBL-E.coli group had higher proportions than non-ESBLs-producing group in the following aspects: Age>65 years,hematological disease,hospital-acquired infection,the hospitalization within previous 3 months,the use of antibiotics,cephalosporins,fluoroquinolones,?-lactam / ?-lactamase inhibitor(BLBLI)in the recent 3 months,chemotherapy in last month and the indwelling of urinary catheter,gastric tube,CVC/PICC catheter in the recent 3 months,the use of immunosuppression agents,and neutropenia.Multivariate Logistic regression analysis revealed that bloodstream infections caused by E.coli had a significant correlation between the following factors: the hospital-acquired infection,urinary catheter insertion in the past 3 months,the use of antibiotics and cephalosporins in recent 3 months,chemotherapy in the past month and neutropenia.Conclusions1.Of the 368 patients diagnosed with bloodstream infections caused by E.coli during the research period,255(69.3%)were ESBLs-producing strains.2.Drug resistance of ESBLs-producing group to most of the antimicrobial agents were significantly higher than non-ESBLs producing group,ESBLs-E.coli had the highest sensitivity to carbapenems.3.Multivariate Logistic regression analysis identified the hospital-acquired infection,urinary catheter insertion in the past 3 months,the use of antibiotics and cephalosporins in recent 3 months,chemotherapy in the past month and neutropenia during infection period as the independent risk factors of bloodstream infections caused by ESBL-E.coli.