title: Bloodstream infections caused by ESBL-producing E. coli and K. pneumoniae: risk factors for multidrug-resistance.
abstract: This prospective case-control study was conducted from October 2003 to June 2007 to evaluate risk factors for multidrug resistance among extended-spectrum-b-lactamase-producing Escherichia coli and Klebsiella spp. (ESBL-EK) isolates in blood cultures. All adult patients (>18 years old) whose blood cultures grew ESBL-EK during the study period were included. An ESBL-EK isolate was defined as MDR if it was resistant to at least one member of following two classes of antibiotics: aminoglycosides (amikacin, gentamicin, or netilmycin) and fluoroquinolones (ofloxacin, or ciprofloxacin). Case patients were those with a MDR ESBL-EK isolate, and control patients were those with a non-MDR ESBL-EK isolate. A total of 94 bloodstream infections, including 37 (39,4%) bloodstream infections with ESBL-producing E. coli and 57 (60,6%) with ESBL-producing K. pneumoniae,in 86 patients were enrolled. Thirty episodes (31.9%) were due to MDR ESBL-EK. The only independent risk factor for MDR ESBL-EK was duration of hospitalization before bacteraemia (OR 3.88; 95% CI 1.55-9.71; p=0.004). The rate of multidrug resistance among ESBL-EK bloodstream isolates was high, and duration of hospitalization before bacteraemia was the only indeepended risk factor for the MDR ESBL-EK bloodstream infections.
authors.affiliation: Baskent University, Medical Faculty, Department of Infectious Diseases and Clinical Microbiology, Ankara, Turkey. kivanc1972@gmail.com
authors.forename: Kivanc
authors.initials: K
authors.lastname: Serefhanoglu
authors.forename: Hale
authors.initials: H
authors.lastname: Turan
authors.forename: Funda Ergin
authors.initials: FE
authors.lastname: Timurkaynak
authors.forename: Hande
authors.initials: H
authors.lastname: Arslan
mesh_terms: D000328:Adult; D000368:Aged; D000617:Aminoglycosides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology; D016022:Case-Control Studies; D003428:Cross Infection / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology; D004927:Escherichia coli Infections / Q000382:microbiology; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D007710:Klebsiella Infections / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D001618:beta-Lactamases