title: Impact of empirical treatment in extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. bacteremia. A multicentric cohort study.
abstract: BACKGROUND
  The objective of this study is to analyze the factors that are associated with the adequacy of empirical antibiotic therapy and its impact in mortality in a large cohort of patients with extended-spectrum β-lactamase (ESBL)--producing Escherichia coli and Klebsiella spp. bacteremia.
  
  
  METHODS
  Cases of ESBL producing Enterobacteriaceae (ESBL-E) bacteremia collected from 2003 through 2008 in 19 hospitals in Spain. Statistical analysis was performed using multivariate logistic regression.
  
  
  RESULTS
  We analyzed 387 cases ESBL-E bloodstream infections. The main sources of bacteremia were urinary tract (55.3%), biliary tract (12.7%), intra-abdominal (8.8%) and unknown origin (9.6%). Among all the 387 episodes, E. coli was isolated from blood cultures in 343 and in 45.71% the ESBL-E was multidrug resistant. Empirical antibiotic treatment was adequate in 48.8% of the cases and the in hospital mortality was 20.9%. In a multivariate analysis adequacy was a risk factor for death [adjusted OR (95% CI): 0.39 (0.31-0.97); P = 0.04], but not in patients without severe sepsis or shock. The class of antibiotic used empirically was not associated with prognosis in adequately treated patients.
  
  
  CONCLUSIONS
  ESBL-E bacteremia has a relatively high mortality that is partly related with a low adequacy of empirical antibiotic treatment. In selected subgroups the relevance of the adequacy of empirical therapy is limited.
authors.affiliation: Instituto de Formación e Investigación Marqués de Valdecilla, 3ª Planta, Edificio IFIMAV, Avda Cardenal Herrera Oria, 39011 Santander, Spain. gpf@mundivia.es
authors.forename: Galo
authors.initials: G
authors.lastname: Peralta
authors.forename: María
authors.initials: M
authors.lastname: Lamelo
authors.forename: Patricia
authors.initials: P
authors.lastname: Alvarez-García
authors.forename: María
authors.initials: M
authors.lastname: Velasco
authors.forename: Alberto
authors.initials: A
authors.lastname: Delgado
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Horcajada
authors.forename: María
authors.initials: M
authors.lastname: Montero
authors.forename: María Pía
authors.initials: MP
authors.lastname: Roiz
authors.forename: Maria Carmen
authors.initials: MC
authors.lastname: Fariñas
authors.forename: Juan
authors.initials: J
authors.lastname: Alonso
authors.forename: Luis Martínez
authors.initials: LM
authors.lastname: Martínez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Gutiérrez-Macías
authors.forename: Jose Angel
authors.initials: JA
authors.lastname: Alava
authors.forename: Azucena
authors.initials: A
authors.lastname: Rodríguez
authors.forename: Ana
authors.initials: A
authors.lastname: Fleites
authors.forename: Vicente
authors.initials: V
authors.lastname: Navarro
authors.forename: Elia
authors.initials: E
authors.lastname: Sirvent
authors.forename: Jose Antonio
authors.initials: JA
authors.lastname: Capdevila
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007709:Klebsiella / Q000201:enzymology* / Q000302:isolation & purification; D007710:Klebsiella Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D008297:Male; D008875:Middle Aged; D013030:Spain; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases