Diagnostic performance and clinical impact of the BioFire FilmArray Pneumonia Panel compared with conventional culture in hospitalized patients with pneumonia

Background Rapid and accurate identification of respiratory pathogens and antimicrobial resistance is essential for optimizing antimicrobial therapy in pneumonia. Conventional culture-based diagnostics are limited by delayed turnaround times and reduced sensitivity, particularly after prior antibiotic exposure. The BioFire FilmArray Pneumonia Panel enables rapid multiplex detection of respiratory pathogens and antimicrobial resistance genes directly from clinical specimens. Objective To evaluate the diagnostic performance and clinical impact of the BioFire FilmArray Pneumonia Panel in hospitalized patients with pneumonia. Methods We conducted a retrospective observational study comparing the diagnostic performance of the FilmArray Pneumonia Panel with conventional culture using 558 bronchoalveolar lavage and sputum specimens collected between December 2022 and December 2023. Diagnostic performance, pathogen detection, antimicrobial resistance genes, and polymicrobial detection patterns were evaluated. The clinical impact of FilmArray implementation was also assessed in 494 hospitalized patients by comparing antibiotic management and clinical outcomes between the FilmArray period and pre-implementation period (January to November 2022). Multivariable regression analyses were performed to adjust for baseline differences. Results The FilmArray panel detected a broad spectrum of bacterial pathogens, respiratory viruses, and antimicrobial resistance genes, with a substantial proportion of specimens being culture-negative but FilmArray-positive, particularly sputum specimens. Compared with the pre-implementation period, the FilmArray period showed a significantly higher frequency of result-driven antibiotic actions (40.5% vs. 26.5%; adjusted odds ratio, 1.86; 95% confidence interval [CI], 1.24–2.79; P = 0.003) and a shorter time from microbiological result reporting to antibiotic action (adjusted mean difference, −0.59 days; 95% CI, −1.07 to −0.10; P = 0.019). Measured from specimen sampling, the interval to the antibiotic action was more than three days shorter (adjusted mean difference, −3.53 days; 95% CI, −4.08 to −2.99; P < 0.001), reflecting the faster turnaround of the panel (median, 0 vs. 3 days). Hospital length of stay was also shorter (adjusted mean difference, −1.61 days; 95% CI, −3.07 to −0.15; P = 0.031). However, total antibiotic exposure was modestly longer (adjusted mean difference, 1.86 days; 95% CI, 0.29–3.44; P = 0.021), and antibiotic de-escalation rates did not differ significantly between the two periods. Conclusions The BioFire FilmArray Pneumonia Panel improved pathogen detection and facilitated earlier and more frequent microbiology-guided antibiotic management, and was associated with a modest reduction in hospital length of stay. However, it modestly increased overall antibiotic exposure and did not increase antibiotic de-escalation. Rapid molecular diagnostics may improve the timeliness and precision of antimicrobial therapy, but their full clinical benefit is likely to be realized only when they are used as a complementary tool alongside conventional microbiological methods and integrated within a structured antimicrobial stewardship program.