641. Evaluation of the FilmArray Pneumonia Panel and Potential Impact of Antimicrobial Use on Patients in a Trauma and Medical Intensive Care Unit

Abstract

BackgroundOrganisms causing infections of the lower respiratory tract in hospitalized patients can lead to high morbidity and mortality. Identification of the agents of pneumonia allows implementation of appropriate antimicrobial therapy and fast and accurate results are essential for the application of the correct antimicrobial regimen.MethodsFor 6 months results of quantitative bronchioalveolar lavage (Q-BALs) respiratory cultures, ordered as a standard of care for patients in our intensive care unit, were compared with the results obtained by a new multiplex molecular assay for the detection of lower respiratory tract pathogens, the FilmArray pneumonia panel (PP). The panel offers semi-quantitation of the bacterial targets that were compared with the quantitative results of the Q-BALs. Additionally, a retrospective chart review was performed to examine whether there would be any difference in the timing of appropriate antimicrobial therapy if the results of the panel were to be available for those patients. Appropriate antimicrobial therapy was determined according to the institution protocol for treatment of patients for ventilator-associated pneumonia based on the results of the quantitative culturesResultsThirty-six unique patients Q-BALs were run and of those there was 82% agreement on the detected targets between cultures and PP. Six targets were not detected by the panel (yeast, S. maltophilia, Streptococci, Salmonella spp.). M. catarrhalis, S. agalactiae and 3 viral targets were detected only by the panel. There was 100% agreement between the panel detected resistance markers and the culture isolates susceptibilities. Of the 36 patients, 12 were excluded because their medical records were not available for review. Of the 24 reviewed, 8 (33.3%) would have de-escalation in their antibiotics use at least 24h earlier due to the PP result. Eight (33.3%) would have no potential change in therapy and 8 (33.3%) could have inappropriate escalation or continuation due to reporting of potential pathogens by the PP but recorded as normal flora by cultures.ConclusionThe use of PP would lead to a reduction of unnecessary antimicrobial therapy in 1/3 of the patients examined. However, quantification of organisms otherwise reported as normal flora may lead to unnecessary treatment and requires education of staff to understand the results of the assay.Disclosures All authors: No reported disclosures.