title: Bloodstream infection with extended-spectrum beta-lactamase-producing Enterobacteriaceae at a tertiary care hospital in New Zealand: risk factors and outcomes.
abstract: OBJECTIVE
  To define local risk factors and outcomes for bacteremia with extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) at a tertiary hospital in New Zealand.
  
  
  METHODS
  Patients with ESBL-E bacteremia were compared to matched control patients with non-ESBL-producing Enterobacteriaceae bacteremia. Patients were matched by onset of bacteremia (community vs. hospital), site of blood culture collection (peripheral vs. via central line), and infecting organism species.
  
  
  RESULTS
  Forty-four cases with matched controls were included. Eight- and 30-day mortality was higher in cases than controls (27% vs. 7%; p=0.011 and 34% vs. 11%, p=0.011). Twenty-one cases (48%) were community-onset. Community-onset cases were associated with urinary tract infection, whereas hospital-onset cases were associated with central line infection, intensive care admission, and Enterobacter cloacae. Independent risk factors for ESBL-E bacteremia were fluoroquinolone exposure (odds ratio (OR) 6.56, 95% confidence interval (CI) 1.79-24), first-generation cephalosporin exposure (OR 12.3, 95% CI 1.01-148), and previously-known colonization with ESBL-E (OR 46.2, 95% CI 3.45-619).
  
  
  CONCLUSIONS
  The association with fluoroquinolone exposure suggests that measures to reduce unnecessary use may be an effective preventative strategy. Known colonization with ESBL-E is a strong risk factor for ESBL-E bacteremia, and colonization status should be taken into consideration when choosing empirical therapy.
authors.affiliation: Department of Clinical Microbiology, LabPlus, PO Box 110031, Auckland City Hospital, Auckland 1148, New Zealand. JoshuaF@adhb.govt.nz
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Freeman
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: McBride
authors.forename: Mitzi S
authors.initials: MS
authors.lastname: Nisbet
authors.forename: Greg D
authors.initials: GD
authors.lastname: Gamble
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Williamson
authors.forename: Susan L
authors.initials: SL
authors.lastname: Taylor
authors.forename: David J
authors.initials: DJ
authors.lastname: Holland
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology* / Q000401:mortality; D001424:Bacterial Infections / Q000188:drug therapy; D002511:Cephalosporins / Q000494:pharmacology / Q000627:therapeutic use; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality; D003428:Cross Infection / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology*; D004756:Enterobacteriaceae Infections / Q000188:drug therapy / Q000382:microbiology* / Q000401:mortality; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology / Q000627:therapeutic use; D006761:Hospitals; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009520:New Zealand / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D024841:Fluoroquinolones; D001618:beta-Lactamases