Implementation of a Rapid Multiplex Polymerase Chain Reaction Pneumonia Panel and Subsequent Antibiotic De-escalation

BACKGROUND: Net effects of implementation of a multiplex polymerase chain reaction (PCR) pneumonia panel (PNP) on antimicrobial stewardship are thus far unknown. This retrospective study evaluated the real-world impact of the PNP on time to antibiotic de-escalation in critically ill patients treated for pneumonia at an academic medical center. METHODS: This retrospective, quasi-experimental study included adult intensive care unit (ICU) patients with respiratory culture results from 1 May to 15 August 2019 (pre-PNP group) and adult ICU patients with PNP results from 1 May to 15 August 2020 (PNP group) at Nebraska Medical Center. Patients were excluded for the following reasons: any preceding positive coronavirus disease 2019 PCR test, lack of antibiotic receipt, or non–respiratory tract infection indications for antibiotics. The primary outcome was time to discontinuation of anti–methicillin-resistant Staphylococcus aureus (MRSA) therapy. Secondary outcomes included time to discontinuation of antipseudomonal therapy, frequency of early discontinuation for atypical coverage, and overall duration (in days) of antibiotic therapy for pneumonia. RESULTS: Sixty-six patients in the pre-PNP group and 58 in the PNP group were included. There were significant differences in patient characteristics between groups. The median time to anti-MRSA agent discontinuation was 49.1 hours in the pre-PNP and 41.8 hours in the PNP group (P = .28). The median time to discontinuation of antipseudomonal agents was 134.4 hours in the pre-PNP versus 98.1 hours in the PNP group (P = .47). Other outcomes were numerically but not significantly improved in our sample. CONCLUSIONS: This early look at implementation of a multiplex PNP did not demonstrate a statistically significant difference in antibiotic use but lays the groundwork to further evaluate a significant real-world impact on antibiotic de-escalation in ICU patients treated for pneumonia.