Editorial Commentary: A Quality-of-Care Bundle for Treatment of Staphylococcus aureus Bacteremia: Ready for Prime Time?

Staphylococcus aureus is the most frequent cause of healthcare-associated bloodstream infections in the United States [1] and among the most common etiologies of bloodstream infections worldwide [2]. By sheer volume alone, S. aureus bacteremia (SAB) imposes a significant burden on the healthcare system. This burden is further amplified by the high likelihood of serious complications associated with this disease including metastatic infections and infective endocarditis. In an analysis of a large database of 59 US hospitals, SAB, and, in particular bacteremia due to methicillin-resistant S. aureus, was associated with a higher mortality, longer length of stay, and greater total hospital charges compared to bacteremia from any other pathogen [1]. The cost per episode of SAB is substantial, especially among high-risk patients; the mean cost among patients undergoing hemodialysis is $24 034 [3] and ranges from $40 000 to $70 000 [4] among those with prosthetic devices. Given the enormous impact of SAB on healthcare resource utilization, there is a major incentive to prevent and optimize management of SAB. Evidence-based bundles of care have received increased attention in recent years as structured ways to improve processes of care and patient outcomes. The fundamental premise is that the entire “bundle” of interventions, when collectively and consistently implemented, results in better outcomes than when the interventions are implemented individually. For example, the central line bundle has been highlighted as one of the most successful and widely adopted bundles of care, resulting in significant and sustained declines in the rates of central line–associated bloodstream infections (CLABSIs) [5, 6]. Between 2001 and 2009, there was a 58% reduction in the overall US CLABSI rate with a 73% reduction in CLABSI due to S. aureus [7]. With respect to management of SAB, multiple studies have demonstrated improved outcomes [8–10] as well as mortality benefit [11–15] among patients with SAB who are managed formally by infectious disease (ID) consultants. In these studies, ID consultation has been shown to increase adherence to several standards (with some variability by study in the standards assessed) that are deemed to be important in the management of patients with SAB including follow-up blood cultures after initial positive, identification of metastatic foci of infection and source control, echocardiography, treatment of methicillinsusceptible infection with β-lactam therapy, and appropriate duration of therapy. The study by Lopez-Cortes et al, published in this issue of Clinical Infectious Diseases, is the first that has evaluated the impact of a standardized bundle of interventions for management of SAB in multiple centers. Lopez-Cortes et al implemented amulticenter intervention including 12 tertiary care hospitals in Spain and applied 6 quality-of-care indicators for management of SAB selected based on review of the literature: (1) follow-up blood cultures 48– 96 hours after initiation of antimicrobial therapy; (2) early source control within 72 hours (ie, catheter removal, abscess drainage); (3) echocardiography in patients with complicated bacteremia or predisposing condition for endocarditis; (4) use of a βlactam antibiotic as definitive therapy for treatment of methicillin-susceptible S. aureus; (5) measurement of vancomycin trough levels with dose adjustment to target levels of 15–20 mg/L; and (6) appropriate treatment duration based on complexity of infection. The intervention Received 22 July 2013; accepted 23 July 2013; electronically published 8 August 2013. Correspondence: Catherine Liu, MD, Division of Infectious Diseases, University of California, San Francisco, 513 Parnassus Ave, S-380, San Francisco, CA 94143 (catherine.liu@ucsf. edu). Clinical Infectious Diseases 2013;57(9):1234–6 © The Author 2013. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals. permissions@oup.com. DOI: 10.1093/cid/cit502