650. Relationship of a Multiplex Molecular Pneumonia Panel (PP) Results with Hospital Outcomes and Clinical Variables

Background The Pneumonia Panel (PP) (BioFire Diagnostics, Salt Lake City, UT) detects 15 potentially pathogenic bacteria semiquantitatively (copy #/mL), 8 viruses and 7 resistance genes from the lower respiratory tract in ≈1 hour in the laboratory. Since identification and susceptibility take ≈ 2 days, this rapid result time is very attractive; however, the clinical significance of the PP copy #/mL as well as a predictable group of PP positive but culture negative patients is unknown. We retrospectively studied the relationship of 270 PP results to culture results, clinical data and outcomes. Methods Bronchoalveolar lavage fluid (N = 197) and endotracheal aspirates (N = 73) submitted to the UF Health Shands Hospital microbiology laboratory from June-September 2018 were frozen at −70°C, until tested on the PP. Patient data were extracted from the inpatient electronic medical record (Epic). Results Of 270 patients tested, 111/270 (41.1%) were PP bacteria negative/culture no growth or normal flora (Group 1), 59/270 (21.9%) were PP positive/culture negative (Group 2), and 100/270 (37.0%) were PP positive/culture positive (Group 3) for at least 1 concordant bacterial potential pathogen. Hospital length of stay (LOS), P = 0.0274, ANOVA; ICU LOS P = 0.0007 and BAL % Polys P < 0.0001 were significantly longer/higher in Group 3 than in Groups 1 and 2 (Table 1). Max daily temp on the day of culture in PP-positive groups 2 and 3 was significantly higher than the PP-negative group 1, P = 0.0260, ANOVA, (Table 1). Age, daily WBC, lowest paO2, max FiO2, % on antibiotics ( ≥80% for all groups), and % with viruses in the PP were not significantly different across groups. When all PP pathogens were grouped by copy # /mL, ICU LOS was significantly longer for 10(7) copies/mL (P = 0.0088), as was BAL % polys (P = 0.0006). Max daily temp was almost significantly higher for PP-positive groups 10(5), 10(6), and 10(7) combined compared with the PP-negative group (Table 2, P = 0.0608). Conclusion Hospital LOS was significantly longer and BAL %Polys higher in the bacterial pathogen culture-positive/PP-positive group vs. not positive groups. ICU LOS and BAL %Polys were significantly higher for the PP-positive groups vs. PP negative regardless of culture results. PP results (copy #/mL) independently correlated with outcome and clinical measures. Disclosures All authors: No reported disclosures.