MRSA
Aiya Almogaber, PharmD
Findings from a recent quality improvement study published in Antimicrobial Stewardship & Healthcare Epidemiology on October 6, 2025, suggests that a focused, pharmacist-driven approach can meaningfully reshape how hospitals use anti-MRSA therapy.
Investigators found that a structured intervention bundle significantly increased the rate of pharmacist involvement in antimicrobial decisions and shifted prescribing behaviors, without adding unwanted complexity to clinical practice.
The intervention involved reassessing and expanding electronic clinical surveillance alerts within the VigiLanz platform, extending MRSA nasal PCR testing beyond pulmonary infections, introducing a standardized “MRSA Antibiotic Time-Out” document combined with pharmacist-focused education, and generating a daily report of active daptomycin, linezolid, and vancomycin orders to guide review.
The findings highlight how targeted stewardship tools can help reduce unnecessary broad-spectrum therapy in an era when MRSA continues to pose a serious resistance threat. Although MRSA is a well-recognized cause of severe infections, broad empiric coverage with agents like vancomycin is often initiated in settings where MRSA is ultimately not the causative organism.
The study authors emphasized that inappropriate or prolonged anti-MRSA therapy contributes to resistance development and preventable adverse events.
The study explored whether a structured bundle, rather than isolated interventions, could amplify pharmacists’ ability to intervene and improve antibiotic use.
The research team evaluated 100 patients before and 100 after implementation. The difference in pharmacist engagement was substantial: 73% of patients in the post-implementation period received at least one pharmacist intervention, compared with 40% prior to the intervention, a statistically significant increase of 33 percentage points.
Specific categories of interventions increased as well. De-escalation rose from 4% to 14%, changes in anti-MRSA agents increased from 8% to 21%, and IV-to-PO conversions rose from 0% to 6%.
Ordering of MRSA nasal PCR also increased, from 5% in the pre-period to 15% post-implementation. Not all measures differed between groups: Discontinuation, dose optimization, and duration adjustments showed no significant changes. Still, the overall number of interventions doubled from 48 to 100, and the provider acceptance rate reached an impressive 93%.
Closer look at anti-MRSA therapy bundle
The project, conducted at a 453-bed community hospital, was centered around a series of coordinated enhancements aimed at improving how anti-MRSA therapy was assessed.
These components worked in concert to ensure that pharmacists could identify opportunities for de-escalation, discontinuation, or optimization in real time. Designated pharmacists across several service lines—antimicrobial stewardship, critical care, and residency—reviewed therapy and completed interventions either per protocol or with direct provider communication.
Effects on antibiotic utilization and clinical outcomes
Hospital-wide adult inpatient days of therapy per 1,000 patient days did not significantly change overall, but agent-specific trends were notable.
Vancomycin use decreased significantly, dropping from 122 days of therapy before the bundle to 87 days afterward.
Utilization of linezolid and daptomycin moved in the opposite direction, though both changes fell short of statistical significance.
Length of stay remained unchanged at 7 days in both groups, and neither adverse drug events nor 30-day all-cause mortality occurred in either cohort, suggesting that increased stewardship activity did not compromise clinical outcomes.
Outside the formal analysis set, 182 patients were reviewed during the intervention period, and 175 total interventions were completed, demonstrating consistent application of the bundle across the hospital.
Interpreting the impact
The investigators noted that bundled approaches align with WHO recommendations emphasizing multimodal strategies for improving clinical processes and outcomes.
In this project, some elements proved more influential than others. For example, nasal MRSA screening for nonpulmonary infections was less productive than anticipated and became de-emphasized later in the post-implementation period. Yet, the bundle’s collective effect was clear. The coordinated structure helped pharmacists intervene more frequently and effectively, supported consistent reevaluation of therapy, and reduced unnecessary exposure to vancomycin.
While the study is limited by its single-center design and short time frame, it adds to a growing body of evidence demonstrating that pharmacist-driven stewardship programs can improve antimicrobial use. ■