Prediction of Fluoroquinolone Resistance in Gram-Negative Bloodstream Infections.
Antimicrob Agents Chemother. 2016 Feb 1;
Authors: Dan S, Shah A, Justo JA, Bookstaver PB, Kohn J, Albrecht H, Al-Hasan MN
Increasing rates of fluoroquinolone resistance (FQ-R) have limited empiric treatment options for gram-negative infections, particularly in patients with severe beta-lactam allergy. This case-control study aims to develop a clinical risk score to predict probability of FQ-R in gram-negative bloodstream isolates. Adult patients with gram-negative bloodstream infections (BSI) hospitalized at Palmetto Health System in Columbia, South Carolina from 2010-2013 were identified. Multivariate logistic regression was used to identify independent risk factors for FQ-R. Point allocation in fluoroquinolone resistance score (FQRS) was based on regression coefficients. Model discrimination was assessed by area under receiver operating characteristic curve (AUC). Among 824 patients with gram-negative BSI, 143 (17%) had BSI due to fluoroquinolone non-susceptible gram-negative bacilli. Independent risk factors for FQ-R and point allocation in FQRS included male sex (adjusted odds ratio [aOR] 1.97, 95% confidence intervals [CI]: 1.36-2.98; 1 point), diabetes mellitus (aOR 1.54, 95% CI: 1.03-2.28; 1 point), residence at a skilled nursing facility (aOR 2.28, 95% CI: 1.42-3.63; 2 points), outpatient procedure within 30 days (aOR 3.68, 95% CI: 1.96-6.78; 3 points), and prior fluoroquinolone use within 90 days (aOR 7.87, 95% CI: 4.53-13.74; 5 points) or within 91-180 days of BSI (aOR 2.77, 95% CI: 1.17-6.16; 3 points). AUC for both final logistic regression and FQRS models was 0.73. Patients with FQRS of 0, 3, 5 and 8 had predicted probability of FQ-R of 6%, 22%, 39% and 69%, respectively. Estimation of patient-specific risk of antimicrobial resistance using FQRS may improve empiric antimicrobial therapy and fluoroquinolone utilization in gram-negative BSI.
PMID: 26833166 [PubMed - as supplied by publisher]