Risk factors for fluoroquinolone-resistant Escherichia coli in adults with community-onset febrile urinary tract infection.
OBJECTIVE
To assess risk factors for fluoroquinolone resistance in community-onset febrile Escherichia coli urinary tract infection (UTI).


METHODS
A nested case-control study within a cohort of consecutive adults with febrile UTI presenting at primary healthcare centres or emergency departments during January 2004 through December 2009. Resistance was defined using EUCAST criteria (ciprofloxacin MIC >1.0 mg/L). Cases were subjects with fluoroquinolone-resistant E. coli, and controls those with fluoroquinolone-susceptible isolates. Multivariable logistic regression analysis was used to identify potential risk factors for fluoroquinolone resistance.


RESULTS
Of 787 consecutive patients, 420 had E. coli-positive urine cultures. Of these, 51 (12%) were fluoroquinolone resistant. Independent risk factors for fluoroquinolone resistance were urinary catheter [odds ratio (OR) 3.1; 95% confidence interval (CI) 0.9-11.6], recent hospitalization (OR 2.0; 95% CI 1.0-4.3) and fluoroquinolone use in the past 6 months (OR 17.5; 95% CI 6.0-50.7). Environmental factors (e.g. contact with animals or hospitalized household members) were not associated with fluoroquinolone resistance. Of fluoroquinolone-resistant strains, 33% were resistant to amoxicillin/clavulanate and 65% to trimethoprim/sulfamethoxazole; 14% were extended-spectrum β-lactamase (ESBL) positive compared with <1% of fluoroquinolone-susceptible isolates.


CONCLUSIONS
Recent hospitalization, urinary catheter and fluoroquinolone use in the past 6 months were independent risk factors for fluoroquinolone resistance in community-onset febrile E. coli UTI. Contact with animals or hospitalized household members was not associated with fluoroquinolone resistance. Fluoroquinolone resistance may be a marker of broader resistance, including ESBL positivity.
Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
Willize E
WE
van der Starre
Cees
C
van Nieuwkoop
Sunita
S
Paltansing
Jan W
JW
van't Wout
Geert H
GH
Groeneveld
Martin J
MJ
Becker
Ted
T
Koster
G Hanke
GH
Wattel-Louis
Nathalie M
NM
Delfos
Hans C
HC
Ablij
Eliane M S
EM
Leyten
Jeanet W
JW
Blom
Jaap T
JT
van Dissel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016022:Case-Control Studies; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014552:Urinary Tract Infections / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones