2010. A Significant Reduction in Empiric Vancomycin Days of Therapy for Suspected MRSA Pneumonia in Adult Non-ICU Patients After Implementation of a Rapid MRSA Nasal PCR Test with Antimicrobial Stewardship Intervention

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA), when implicated in respiratory tract infections, can be associated with significant morbidity and mortality. The prevalence of severe MRSA pneumonia may be as high as 10%; however, recent evidence suggests that MRSA is much less prevalent as a cause of community-acquired pneumonia (CAP) among community-dwelling patients and may be as low as 0.1%. Nonspecific features of pneumonia in non-ICU patients (viral co-infection, multi-lobar infiltrates) often lead clinicians to cautiously initiate empiric anti-MRSA therapy. Recommendations of when to safely de-escalate empiric treatment prior to known respiratory cultures are not established. To decrease anti-MRSA therapy in non-ICU pneumonia patients with a low probability of MRSA pneumonia, we employed a nasal screening paired with antimicrobial stewardship intervention. METHODS: A retrospective, single-center, pre-post interventional study was conducted at Northwestern Memorial Hospital (NMH), in Chicago, IL, to assess the duration of empiric vancomycin for suspected MRSA pneumonia in non-ICU patients before (January 2019) and after (March 2019) the implementation of a rapid MRSA nasal PCR test. During the post-implementation period, an NMH Antimicrobial Stewardship (AS) member identified and assessed the daily (M-F) use of empiric vancomycin for pneumonia in non-ICU patients. When vancomycin use criteria were not met, the AS pharmacist requested the team order a BD MRSA Nasal PCR test (NPV: 97.2%) to classify patients as either possible MRSA pneumonia or unlikely MRSA pneumonia. Results of a negative MRSA Nasal PCR with an ongoing clinical disposition not suggestive of MRSA pneumonia prompted the AS pharmacist to recommend de-escalation of vancomycin. RESULTS: See table. CONCLUSION: The use of a rapid MRSA nasal PCR test with active antimicrobial stewardship intervention significantly reduced the duration of empiric vancomycin in hospitalized non-ICU patients with suspected MRSA pneumonia. [Image: see text] DISCLOSURES: All authors: No reported disclosures.