Use of a molecular syndromic panel for the etiological diagnosis of ventilator-associated bacterial pneumonia: impact on clinical outcomes and antibiotic use from a multicenter, prospective study

Background: Ventilator-associated bacterial pneumonia (VABP) is a common infection in critically ill patients in intensive care units (ICU), with attributable mortality of up to 13%, and its etiological diagnosis remains challenging. Materials and methods: We conducted a multicenter, prospective, observational study within the MULTI-SITA platform to assess the impact on relevant clinical and antimicrobial stewardship outcomes of the use of a molecular syndromic panel (BIOFIRE® FILMARRAY® Pneumonia plus), in addition to a standard approach based on culture. The primary outcome measure was 30-day mortality from VABP onset. Results: Overall, 237 patients with VABP were included in the study. In multivariable analysis, SOFA score (hazard ratio [HR] 1.13, 95% confidence interval [CI] 1.04–1.22, p = 0.003), previous isolation of carbapenem-resistant Pseudomonas aeruginosa (HR 3.02, 95% CI 1.25–7.32, p = 0.015), and solid neoplasm (HR 2.15, 95% CI 1.12–4.14, p = 0.022) were associated with increased mortality, while no association was registered for the molecular syndromic panel performed (HR 1.07, 95% CI 0.59–1.93, p = 0.825). In secondary analyses, use of the molecular syndromic panel resulted in more events of either de-escalation or initiation of appropriate antibiotic therapy at day 1 from VABP onset in comparison with a standard approach based on culture only (41.3% vs. 27.8%, p = 0.041). Conclusion: The use of a molecular syndromic panel in patients with VABP was able to impact antibiotic decisions, without an unfavorable effect on mortality. Further study is necessary to assess the long-term effects in terms of antimicrobial stewardship of molecular syndromic panels-based antibiotic treatment decisions. Supplementary information: The online version contains supplementary material available at 10.1186/s13054-025-05632-z.