Implementation of Methicillin-Resistant Staphylococcus aureus (MRSA) Nasal Polymerase Chain Reaction (PCR) Screening in Pediatric Patients for De-escalation of Antibiotics.

Objective: Recent literature supports the use of methicillin-resistant Staphylococcus aureus (MRSA) nasal polymerase chain reaction (PCR) screening to guide de-escalation of anti-MRSA antibiotics. The objective of this study was to expand on the limited pediatric data, encouraging the use of MRSA nasal PCRs as a tool to guide de-escalation of anti-MRSA antibiotics.

Methods: This single center, pre- and post-interventional, retrospective cohort study compared antibiotic regimens in pediatric patients treated empirically with anti-MRSA antibiotics, with and without MRSA nasal PCRs. Use of MRSA nasal PCRs in the pediatric hospital was encouraged following an antimicrobial stewardship provider-led continuing education presentation. The primary outcome was duration of therapy of anti-MRSA antibiotics in days. Secondary outcomes included positive predictive values (PPVs) and negative predictive values (NPVs) for all infections, pneumonia, and skin and soft tissue infections.

Results: A total of 319 patients were included in the study, 252 in the pre-intervention group and 67 in the post-intervention group. The duration of anti-MRSA antibiotic therapy in the pre-intervention group was 6.6 days compared with the post-intervention group at 2.0 days (p value = 0.027). Using data from 38 patients with concordant culture results for the infectious diagnosis, overall NPV was calculated as 92.1%. Skin and soft tissue infections and pneumonia were found to have NPVs of 90.1% (22 patients) and 100% (5 patients), respectively.

Conclusion: Implementation of MRSA nasal PCRs in pediatric patients significantly reduced the duration of anti-MRSA antibiotic therapy, promoting their utility for antimicrobial stewardship.