Discontinuation Patterns and Cost Avoidance of a Pharmacist-Driven Methicillin-Resistant Staphylococcus aureus Nasal Polymerase Chain Reaction Testing Protocol for De-escalation of Empiric Vancomycin for Suspected Pneumonia

Abstract

A pharmacist-driven MRSA nasal PCR-based testing protocol with a 70% acceptance rate for vancomycin discontinuation within 24 hours of negative results significantly reduced unnecessary vancomycin use with an estimated cost avoidance of $40 per vancomycin course. We found high concordance (141/147, 96%) of culture-based vs PCR-based MRSA nasal screening.

Comparison of Methicillin-Resistant Staphylococcus aureus Nasal Screening Predictive Value in the Intensive Care Unit and General Ward

“…Although the PCR test is more expensive, cost avoidance of $40.33 per patient has been realized following PCR implementation in facilitating rapid MRSA therapy de-escalation. 13 Our study is not without limitations. The retrospective study design may have contributed to bias.…”

“…Although the PCR test is more expensive, cost avoidance of $40.33 per patient has been realized following PCR implementation in facilitating rapid MRSA therapy de-escalation. 13…”

“…11 Several studies have shown high concordance between PCR- and culture-based MRSA nasal screening approaches with both methods demonstrating a high negative predictive value and/or specificity of ruling out MRSA pneumonia. 12,13 Although several studies have evaluated the clinical utility of the MRSA PCR nares, there remains a paucity of data on the diagnostic performance of the culture-based method for pneumonia as well as bacteremia. 10,14 However, previously published reports using the culture-based MRSA screening method were limited by not reporting MRSA prevalence rates, or inconsistent in obtaining the MRSA screening in close proximity of the microbiologic culture sample for suspected pneumonia or bacteremia.…”

Clinical Microbiology in 2021: My Favorite Studies about Everything Except My Least Favorite Virus

“…PCR-based methicillin-resistant Staphylococcus aureus (MRSA) screening and active antimicrobial stewardship for patients with vancomycin ordered due to suspected pneumonia lead to cost savings outside of the microbiology laboratory and can spare some patient's kidneys from unnecessary vancomycin. Meng et al performed a pre-post intervention study of total institutional costs associated with nares swab MRSA testing by PCR used to intervene in patients with vancomycin ordered during episodes of suspected pneumonia, including consideration of the costs of labor time for technologists and pharmacists, pharmacy expense for vancomycin, and laboratory reagent costs for both MRSA PCR and vancomycin level testing [ 39 ]. They estimated savings of about $40 patient, which is nice enough on its own, but the bigger issue is sparing the patients unnecessary exposure to vancomycin and reduced risk of selective pressure on potential vancomycin-resistant organisms.…”

Assessing the Predictive Value of Methicillin-Resistant Staphylococcus aureus Nares Colonization Among Transplant Recipients and Patients With Neutropenia

“…Methicillin-resistant Staphylococcus aureus (MRSA) nares polymerase chain reaction (PCR) screening has proven to have a high negative predictive value (NPV) for MRSA infections across a variety of anatomical sites within 7 days of microbiological culture [ 1 , 2 ]. This has allowed for the confident de-escalation and avoidance of empiric anti-MRSA treatment before the finalization of cultures [ 3 , 4 ]. However, MRSA nares screening is not well validated in high-risk individuals, including those with neutropenia, hematopoietic stem cell transplant (HSCT) recipients, and solid organ transplant (SOT) recipients [ 5 , 6 ].…”