Heyliger, Jamie

OBJECTIVE Overuse of broad-spectrum empiric antimicrobials remains common in children hospitalized with respiratory tract infections (RTI). A negative methicillin-resistant Staphylococcus aureus (MRSA) nasal swab (MNS) polymerase chain reaction (PCR) result has been shown to have a high negative predictive value for MRSA in RTI. In this quality improvement (QI) initiative, we developed a pharmacist-driven approach to reduce the duration of empiric vancomycin for RTI in children. The primary aim was the time to de-escalation of vancomycin, and the secondary aim was the reduction in vancomycin monitoring in patients hospitalized with RTI. METHODS Baseline duration of vancomycin therapy was assessed by conducting a retrospective chart review. After root cause analysis and engaging key stakeholders, an electronic health record OurPractice Advisory (OPA) was implemented, prompting pharmacists to order an MNS PCR during order verification for vancomycin with an RTI indication. RESULTS Preimplementation (01/01/2021 to 08/31/2023) included 89 patients, and 25 postimplementation (09/21/2023 to 05/31/2024). We found a 36% decrease in mean vancomycin duration from 53 to 34 hours after implementation of the pharmacist-driven OPA. Postimplementation, 24% of patients had a vancomycin concentration obtained, compared with 37% preimplementation. No patients were readmitted within 30 days postimplementation, compared with 1 patient preimplementation. CONCLUSIONS This QI initiative provides preliminary data that empiric vancomycin duration in pediatric patients with RTI may be impacted by pharmacist-facing OPA implementation, prompting ordering of MNS PCR at the time of vancomycin verification. This initiative could be replicated at other institutions seeking to reduce empiric vancomycin usage.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) can cause serious infections and empiric treatment regimens in children frequently include an anti-MRSA antibiotic. Studies in adults have demonstrated a high negative predictive value (NPV) of MRSA nasal swabs (MNS) in a variety of infectious syndromes. Negative MNS have been utilized as a tool to guide de-escalation of anti-MRSA antibiotics in adults, especially in those with lower respiratory tract infections, but data in children is minimal. The primary objective of this study was to determine the NPV and positive predictive value (PPV) of MNS in children hospitalized for treatment of an infection. Methods: This was a single-site, retrospective cohort study of pediatric patients admitted with a suspected infectious diagnosis who had an MNS performed during their hospitalization between June 1, 2018 and November 25, 2022. Results: This study identified 172 patients who met the inclusion criteria. Eleven (6.4%) nasal swabs were positive for MRSA and 10 (5.8%) microbiological cultures from suspected sources of infection were identified to be positive for MRSA. The MNS was found to have a sensitivity of 20%, specificity of 94%, PPV of 18% and NPV of 95% for all sites of infection. Conclusion: MNS has a high NPV and low PPV in children. MNS can be utilized as an antimicrobial stewardship tool to guide the safe de-escalation of anti-MRSA antibiotics in children.