dc.description.abstract | Objective: case-control study was conducted in order to identify the risk factors associated with bloodstream infection caused by extended-spectrum-β- lactamase (ESBL) producing Escherichia coli (E. coli). Secondly, to evaluate the impact of different antibiotics and adequate empirical treatment on clinical outcomes. And also to find out the risk factors for mortality of ESBL-producing E. coli bacteremia in order to provide a concept for clinicians to choose appropriate antibiotic therapy. esign: retrospective case-control chart-review study was conducted during a 30-month period between Jaunary 2005 and June 2007.etting:ational Taiwan University Hospital---a 2200-bed teaching hospital in northern Taiwanatients:oth case and control patients were identified by systemically reviewing the results from the microbiology laboratory. “Case patients” were those who had ESBL-positive E. coli bactermia. One case patient was matched with one control patient according to the closest date to isolation of ESBL-positive E. coli. “Control patients” were those who had ESBL-negitive E. coli bacteremia. We only included the first episode of each patient. ethods:ata were collected from medical records and hospital computerized databases. The records for each patient including patients’ profiles, underlying diseases and comorbidities, the informations about this admission, previous hospitalization histories, previous E. coli infection or colonization histories, antibiotics exposure before bacteremia onset, clinical presentations when bacteremia onset, antibiotic regimens during treatment period, clinical outcomes after bacteremia onset. The primary endpoint was 30-day mortality. isk factors and clinical outcomes were examed using univariate analysis and muitiple logistic regression analysis. Survival curves shown by Kaplan-Meier method were compared with Log-rank test.esults:uring the study period, there were 97 patients of ESBL E. coli bacteremia, 5 patients were excluded because of incomplete follow up and 1 patient with missing chart. Then 91 control patients were matched. In case group, there were 71 (78.0%) monomicrobial infections and 20 polymicrobial infections. The 30 day mortality was 28.6% (26/91) in the case group, compared to 9.9% (9/91) in the control group (p = 0.001).By multivariate analysis, urinary catheterization [odds ratio(OR)6.21, p = 0.003], previous treatment with 3rd、4th-cephalosporins [odds ratio(OR)5.16, p = 0.046], prior exposure to antibiotics [odds ratio(OR)2.93, p = 0.021] were independent predictors for ESBL production. On the contrary, community-acquired infection [odds ratio(OR)0.22, p = 0.002] was a protective factor for ESBL production. Analyses of treatment outcomes showed that there was no significant difference between patients received adequate or inadequate empirical therapy for case patients (p = 0.382) and monomicrobial infection patients (p = 0.233). Comparison between carbapenem and non-carbapenem treatment groups also showed no significant influence on the 30-day mortality (p = 0.703). Multivariate logistic regression analysis for all case patients showed that ICU-acquired [odds ratio(OR)7.47, p = 0.006], immunocompromised patients [odds ratio(OR)3.82, p = 0.018], primary bacteremia [odds ratio(OR)3.15, p = 0.045] were independent risk factors for 30-day mortality. The results from monomicrobial infection patients showed that septic shock [odds ratio(OR)7.01, p = 0.003], ICU-acquired [odds ratio(OR)6.92, p = 0.017] were risk factor for 30-day mortality. onclusions:ur results showed that prior exposure antibiotics, especially 3rd or 4th- cephalosporins, and urinary catheterization were independent predictors for ESBL production. On the contrary, community-acquired infection was a predictor for non-ESBL E. coli bacteremia. Appropriateness of empirical therapy and regimens of definitive therapy did not significantly influence mortality on day 30 in our study. Carbapenem is still the drug of choice for severe patients. Immunocompromised patients, primary bacteremia, septic shock and ICU-acquired infection had a significant impact on day 30 mortality. eywords:xtended-spectrum-β- lactamase(ESBL), Escherichia coli(E. coli), bacteremia, risk factor, resistant, case-control study, treatment outcome, mortality | en |