Inappropriate Continued Empirical Vancomycin Use in a Hospital with a High Prevalence of Methicillin-Resistant Staphylococcus aureus

Vancomycin is frequently inappropriately prescribed, especially as empirical treatment. The aim of this study was to evaluate (i) the amount of inappropriate continued empirical vancomycin use as a proportion of total vancomycin use and (ii) the risk fac-tors associated with inappropriate continued empirical vancomycin use. We reviewed the medical records of adult patients who had been prescribed at least one dose of parenterally administered vancomycin between January and June 2012, in a single ter-tiary care hospital.When empirically prescribed vancomycin treatmentwas continued after 96 hwithout documentation of beta-lactam-resistantGram-positivemicroorganisms in clinical specimenswith significance, the continuationwas considered inappropri-ate, and the amount used thereafterwas considered inappropriately used.We identified risk factors associatedwith inappropriate continued empirical vancomycin use bymultiple logistic regression.During the study period, the amount of parenterally administered vancomycin prescribedwas 34.2 defined daily doses (DDDs)/1,000 patient-days (1,084 prescriptions for 971 patients). The amount of inappropriate continued empirical vancomycin usewas 8.5DDDs/1,000 patient-days, which represented 24.9%of the total parenter-ally administered vancomycin used (8.5/34.2DDDs/1,000 patient-days). Bymultivariate analyses, inappropriate continued empirical vancomycin usewas independently associatedwith the absence of any documented etiological organism (adjusted odds ratio [aOR], 1.60 [95%confidence interval {CI}, 1.06 to 2.41]) and suspected central nervous system (CNS) infections (aHR, 2.33 [95%CI, 1.20 t