Risk factors for fluoroquinolone resistance in Gram-negative bacilli causing healthcare-acquired urinary tract infections

Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6021, USA.
The Journal of hospital infection (Impact Factor: 2.78). 12/2010; 76(4):324-7. DOI: 10.1016/j.jhin.2010.05.023
Source: PubMed

ABSTRACT The prevalence of urinary tract infections caused by fluoroquinolone-resistant Gram-negative bacilli (FQ-resistant GNB-UTIs) has been increasing. Previous studies that explored risk factors for FQ resistance have focused only on UTIs caused by Escherichia coli and/or failed to distinguish colonisation from infection. We conducted a case-control study at two medical centres within the University of Pennsylvania Health System to identify risk factors for FQ resistance among healthcare-acquired GNB-UTIs. Subjects with positive urine cultures for GNB and who met Centers for Disease Control and Prevention criteria for healthcare-acquired UTI were eligible. Cases were subjects with FQ-resistant GNB-UTI and controls were subjects with FQ-susceptible GNB-UTI matched to cases by month of isolation and species of infecting organism. In total, 251 cases and 263 controls were included from 1 January 2003 to 31 March 2005. Independent risk factors (adjusted odds ratio; 95% confidence interval) for FQ resistance included male sex (2.03; 1.21-3.39; P=0.007), African-American race (1.80; 1.10-2.94; P=0.020), chronic respiratory disease (2.58; 1.18-5.62; P=0.017), residence in a long term care facility (4.41; 1.79-10.88; P=0.001), hospitalisation within the past two weeks (2.19; 1.31-3.64; P=0.003), hospitalisation under a medical service (2.72; 1.63-4.54; P<0.001), recent FQ exposure (15.73; 6.15-40.26; P<0.001), recent cotrimoxazole exposure (2.49; 1.07-5.79; P=0.033), and recent metronidazole exposure (2.89; 1.48-5.65; P=0.002).


Available from: Pam Tolomeo, Mar 31, 2014
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    ABSTRACT: In France, according to the National Epidemiology Observatory of Bacterial Resistance to Antibiotics, 15.3% of outpatient urinary Escherichia coli isolates were fluoroquinolone-resistant in 2010. This puts to question the relevance of empirical fluoroquinolone therapy for community-acquired acute pyelonephritis (APN), potentially severe infections. We had for aim to identify individual risk factors for quinolone-resistant E. coli in community-acquired APN. A retrospective cohort study of 344 adult female patients presenting with E. coli APN was conducted at the Roanne and Saint-Etienne hospital emergency departments, from January 2011 to February 2012. We studied the demographic, administrative, and clinical factors. E. coli strains with intermediate susceptibility on the antibiogram were considered as resistant. There was 23% of isolates that were resistant to nalidixic acid and 17.4% to ofloxacin. Complicated APN was not a significant risk factor (univariate analysis). Three risk factors of resistance to nalidixic acid and ofloxacin were independent (multivariate analysis): fluoroquinolone use in the previous 3 months, hospitalization in the previous 6 months, and stay in a long-term care facility. The resistance to ofloxacin reached 30.6% if at least 1 of these risk factors was present; it was 9% when none of the factors were present. These results suggest that local recommendations for the empirical therapy of APN should be reviewed. The limitations of our study require backing up our results with prospective multicentric studies that could lead to drafting new national recommendations.
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