OBJECTIVES : Data demonstrating the clinical and economic impact of antimicrobial resistance (AMR) at local levels is not well captured and analyzed. We performed an evaluation of the burden of AMR within an acute care setting in Canada for the top 5 resistant organisms: Klebsiella pneumonia, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus.

METHODS : An economic model was developed using data from the literature and data extracted from hospital-generated antibiograms at a 442-bed hospital. Direct and indirect costs per year attributed to acute care facilities were included, in concordance with the hospital perspective. Three future rates for resistance were included: low (20%), medium (50%) and high (100%).We searched Medline for resistance rates, mortality, and micro-costing data. Articles met inclusion criteria if they were primary clinical studies evaluating relevant pathogens across all syndromes within Canadian hospitals, published after 12/31/2009. The number of isolates extracted from hospital-generated antibiograms was used as a proxy for total number and distribution of relevant infections. Data describing the cost of methicillin-resistant Staphylococcus aureus bacteremia and extended-spectrum β-lactamase producing Klebsiella pneumonia and Escherichia coli were extrapolated to the other conditions, based on clinical expert opinion.

RESULTS : The top 5 infections cost $10.2 million to manage at an acute care center. The incremental cost of resistance is $1.2 million. At 100% resistance, the burden could rise to as much as $30 million and nearly 700 deaths, with an $18 million avoidable cost of resistance. The main limitation of the study is the lack of published data describing the incremental costs of resistant infections compared to susceptible infections.

CONCLUSIONS : This tool delivers the ability to estimate the clinical and economic burden of AMR within an acute care setting. Efforts should be made to improve surveillance and accessibility of data to support micro-costing initiatives.