Methods: Fungi (7) and bacteria (19) were independently seeded in blood samples, inoculated into as many as 8 different types of blood culture bottles, and incubated on the recommended instrument. Time to positivity (TTP) was recorded for all PBCs. Subsets of PBCs were enumerated and tested on the BioFire BCID2 Panel and BioFire® FilmArray® Blood Culture Identification (BCID) Panel. Polymicrobial testing was performed by seeding fast and slow growing organisms into the same bottles.
Results: Over 750 PBCs were enumerated; ~500 PBCs were tested on the BioFire BCID2, and over 200 were also tested on the BioFire BCID. 100% of seeded PBCs tested on the BioFire Panels resulted in correct pathogen identification. Across all bottle types, fungi grew to levels ranging from 8E+05 to 5E+07 CFU/mL, Gram+ bacteria titers ranged from 7E+06 to 2E+09, and Gram- bacteria titers ranged from 9E+07 to 3E+09. Polymicrobial PBCs (30) had reduced titers of slow growing organisms when seeded with fast growing organisms but were detected by both BioFire BCID Panels at a rate of 99%.
Conclusion: This study demonstrates that a prototype BioFire BCID2 Panel, and the BioFire BCID Panel, robustly detect and identify (100%) BSI pathogens over a multitude of common blood culture media and systems. Results confirm PBC (single & polymicrobial) titers are above the levels of sensitivity for both BioFire panels. An expanded menu of targets (organism & resistance) and faster run time with the BioFire BCID2 Panel will offer a flexible and comprehensive aid in the diagnosis of BSIs.
The BioFire® BCID2 Panel has not yet been evaluated by the FDA or other regulatory agencies for in vitro diagnostic use.
BioFire Diagnostics, LLC:
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