Beyond the Petri Dish: The Performance of a Multiplex PCR-Based Pneumonia Panel in Hospitalized Patients With Lower Respiratory Tract Infection

Background Lower respiratory tract infections (LRTIs) are a major cause of mortality in intensive care units (ICUs), necessitating rapid pathogen identification. This study evaluates the diagnostic performance of the multiplex polymerase chain reaction (PCR)‑based BioFire® FilmArray® Pneumonia Panel (BFPP) compared to conventional culture in hospitalized patients with LRTI at a tertiary care center. Methodology This retrospective observational study was carried out at a tertiary care hospital between January 2023 and June 2024. Bronchoalveolar lavage (BAL) culture and antibiotic sensitivity testing (ABST) data of individuals suspected to have LRTI were retrieved and compared to BFPP results for concordance. Results A total of 261 bronchoalveolar lavage (BAL) specimens were analyzed using the BFPP. Overall, BFPP detected 562 pathogens, comprising 419 bacterial isolates, 139 viral pathogens, and four atypical bacteria. Polymicrobial infections were identified in 33% of the specimens. Among the antimicrobial resistance determinants detected, New Delhi metallo‑β‑lactamase (NDM) genes were the most prevalent (33%), followed by cefotaxime-Munich (CTX‑M)-like (25%) and oxacillinase-48 (OXA‑48)-like genes (18%). Concordance analysis between BFPP and conventional culture was feasible in 143 samples, demonstrating an overall agreement of 72%. Using conventional culture as the reference standard, the BFPP assay showed a sensitivity of 90.2% and a specificity of 57.8%. The positive predictive value was 75.5%, while the negative predictive value was 80.5%. Notably, BFPP provided results significantly earlier than culture, with an average turnaround time advantage of approximately 52 hours. Conclusion BFPP improves detection rates of respiratory pathogens and shortens the turnaround time. The detection of antimicrobial resistance genes helps clinicians to initiate timely antibiotics and can play a pivotal role in antimicrobial stewardship.