Bloodstream infections due to vancomycin-resistant enterococci (VRE-BSI) result in substantial patient mortality and cost. Daptomycin (D) and Linezolid (L) are commonly prescribed for VRE-BSI, but there are no clinical trials to determine optimal antibiotic selection. Major advances have been made using real world comparative effectiveness analysis to define optimal antibiotic selection. However, VRE-BSI research frequently fails to consider the effect of clinical decision making and changing antibiotics during treatment and therefore loses an opportunity to help define optimal clinical practice.
Cohort study of patients with VRE-BSI at Ronald Reagan Medical Center between January 2005 and December 2011. Patients with positive blood cultures, signs of infection, and treatment with antibiotics were included in the analysis. Medical records were reviewed and data abstracted using a standardized instrument for demographic information, presence of co-morbidities, laboratory data, antimicrobial treatment, and outcomes. Data analysis was conducted with descriptive statistics (chi-square, Fisher’s exact).
A total of 253 patients had VRE-BSI; 167 treated with L and 60 with D. L and D treated cohorts differed in CHF (L=17/167 v D 13/60, p=0.04), history of MI (L=16/167 v D 13/60, p=0.02), and liver disease (L=82/167 v D 14/60, p<0.001), but did not differ in Horn’s Index, transplant status, or immunosuppression. Among L treated patient, 26/167 were treated with a concomitant SSRI. In unadjusted analysis, L and D did not differ in time to mortality (p=0.88) or inpatient mortality (L 81/167 v D 30/60, O.R. 0.94, p=0.88). Over 25% of patients (64/253) had a change in antibiotic therapy due to lack of effectiveness. L was less commonly changed for lack of effectiveness (40/167 v D 24/60, p=0.03).
Patients with VRE-BSI have significant morbidity and mortality. Comparative effectiveness analysis of real-world practice are still needed to best define optimal treatment and best clinical practices. Further research is required to better understand changes in antibiotic therapy for patients with VRE-BSI.
J. A. Mckinnell,
P. Injean, None
D. Whang, None
R. Humphries, None
A. Gregson, None