title: Costs of bloodstream infections caused by Escherichia coli and influence of extended-spectrum-beta-lactamase production and inadequate initial antibiotic therapy.
abstract: Escherichia coli is the leading cause of bloodstream infections (BSIs) caused by Gram-negative bacteria. The increasing prevalence of antibiotic-resistant E. coli strains, particularly those producing extended-spectrum β-lactamases (ESBLs), increases the odds that empirically prescribed antimicrobial therapy for these infections will be inadequate, but the economic impact of this risk has not been fully evaluated. In the present retrospective 1-year analysis of 134 consecutive E. coli BSIs in our hospital, we explored the clinical and economic impacts of (i) inadequate initial antimicrobial treatment (IIAT) (i.e., empirical treatment with drugs to which the isolate had displayed in vitro resistance) of these infections and (ii) ESBL production by the bloodstream isolate. Cost data were obtained from the hospital accounting system. Compared with the 107 (79.8%) adequately treated patients, the 27 (20.1%) who received IIAT had a higher proportion of ESBL BSIs (74.0% versus 15.8%), longer (+6 days) and more costly (+EUR 4,322.00) post-BSI-onset hospital stays, and higher 21-day mortality rates (40.7% versus 5.6%). Compared with the 97 non-ESBL infections, the 37 (27.6%) ESBL BSIs were also associated with longer (+7 days) and more costly (+EUR 5,026.00) post-BSI-onset hospital stays and increased 21-day mortality (29.7% versus 6.1%). These findings confirm that the hospital costs and mortality associated with E. coli BSIs are significantly increased by ESBL production and by IIAT.
authors.affiliation: Institutes of Infectious Diseases, Hospital Pharmacy,5 Catholic University of the Sacred Heart, Largo A Gemelli 8, 00168 Rome, Italy. tumbarello@rm.unicatt.it
authors.forename: Mario
authors.initials: M
authors.lastname: Tumbarello
authors.forename: Teresa
authors.initials: T
authors.lastname: Spanu
authors.forename: Rossella
authors.initials: R
authors.lastname: Di Bidino
authors.forename: Marco
authors.initials: M
authors.lastname: Marchetti
authors.forename: Matteo
authors.initials: M
authors.lastname: Ruggeri
authors.forename: Enrico Maria
authors.initials: EM
authors.lastname: Trecarichi
authors.forename: Gennaro
authors.initials: G
authors.lastname: De Pascale
authors.forename: Enrica Maria
authors.initials: EM
authors.lastname: Proli
authors.forename: Roberto
authors.initials: R
authors.lastname: Cauda
authors.forename: Americo
authors.initials: A
authors.lastname: Cicchetti
authors.forename: Giovanni
authors.initials: G
authors.lastname: Fadda
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000191:economics* / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000191:economics*; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000191:economics*; D005260:Female; D006760:Hospitalization / Q000191:economics; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases