Antimicrobial Stewardship Opportunities in Patients with Bacteremia Not Identified by BioFire FilmArray

Area of Science:

• Clinical Microbiology
• Infectious Diseases
• Diagnostic Technology

Background:

• Rapid diagnostic platforms like BioFire BCID are crucial for timely bacteremia management.
• A subset of bacteremia cases are caused by organisms not detected by current rapid diagnostics, leading to unknown clinical characteristics and outcomes.

Purpose of the Study:

• To compare clinical characteristics, antibiotic therapy, and outcomes between bacteremia cases detected (PB-PC) and not detected (NB-PC) by the BioFire BCID platform.
• To identify the types of organisms missed by the BioFire BCID platform and assess the impact on patient management and outcomes.

Main Methods:

• Retrospective analysis of 1,044 positive blood cultures over 15 months.
• Patients were grouped into NB-PC and PB-PC based on BioFire BCID results.
• Comparison of demographics, infection characteristics, antibiotic therapy, length of hospital stay (LOS), and in-hospital mortality.

Main Results:

• Six percent of positive blood cultures were NB-PC, with anaerobes (Bacteroides, Clostridium, Fusobacterium) identified in 57% by conventional methods.
• NB-PC cases experienced a 2-day delay in pathogen identification, more frequent unknown and pelvic sources of bacteremia, and received less effective antibiotic treatment.
• NB-PC patients had significantly higher in-hospital mortality (26% vs 8%, P < 0.01) despite similar LOS.

Conclusions:

• The BioFire BCID platform misses clinically significant organisms, primarily anaerobes, in a subset of bacteremia cases.
• Failure to detect these organisms leads to delayed effective antibiotic therapy and increased patient mortality.
• Enhancements to rapid diagnostic platforms to include anaerobe detection are necessary for improved bacteremia management.