101. Diagnostic Utility of a Multiplex PCR Meningitis/Encephalitis Panel and Impact on Antibiotic Use

BACKGROUND: The detection and identification of meningitis and encephalitis pathogens from CSF via traditional microbiologic methods may take several hours to days. The BioFire FilmArray Meningitis/Encephalitis Panel (BioFire), approved by the FDA in 2015, can detect 14 different pathogens within one hour, providing a faster time to diagnosis of a broad range of pathogens. The purpose of this study was to examine the impact of BioFire on length of hospital stay and duration of antibiotic use. METHODS: We conducted a retrospective chart review of patients diagnosed meningitis/encephalitis between 2015 and 2019 at 3 Beaumont Health (BH) hospitals. BioFire was adopted by BH midyear in 2017, allowing for analysis of cohorts over comparable periods before and after the introduction of the panel. Data collected and analyzed included biodemographics, comorbidities, presenting signs and symptoms, CSF analysis results, pathogens, days of antibiotic therapy, length of stay, and mortality. RESULTS: A total of 161 patients diagnosed with meningitis and/or encephalitis were reviewed, including 59 who underwent testing via BioFire. Of the 161 patients, 68 had a pathogen identified, 50 via traditional methods (6 bacterial and 44 viral) and 18 via BioFire (3 bacterial and 15 viral). West Nile Virus accounted for 17 of the viral infections diagnosed via traditional methods. The mean duration of antibiotic use after the assays resulted was not significantly different between patients with bacterial infections diagnosed by traditional methods or BioFire (11.2 vs 13.0 days, p=0.82) or for those with viral infections (0.1 vs 0 days, p=0.3). The median length of stay was also not significantly different between the two cohorts for patients with bacterial infections (21.7 vs 15.0 days, p = 0.36) or viral infections (6.2 vs. 10.0 days, p = 0.10). CONCLUSION: While utilization of the BioFire panel yielded a faster diagnostic result, we have no evidence to demonstrate that it contributes to a significant reduction in duration of antibiotic use or length of stay. DISCLOSURES: All Authors: No reported disclosures