A-092 Application of the FilmArray® Meningitis/Encephalitis Panel in the Etiological Diagnosis of Suspected Meningitis: A Multiregional Study in Brazil

Abstract

Acute meningitis and encephalitis are medical emergencies that require rapid etiologic identification to guide targeted antimicrobial therapy and improve outcomes. Conventional diagnostic methods, including culture and targeted molecular assays, may be time-consuming and/or limited in pathogen coverage. Multiplex molecular panels, such as the FilmArray® Meningitis/Encephalitis (ME) Panel, enable simultaneous detection of bacterial, viral, and fungal targets directly from cerebrospinal fluid (CSF) and represent an advance in laboratory diagnostics for central nervous system infections. The aim of this study was to evaluate real-world diagnostic yield, detected pathogens, turnaround time (TAT), and agreement with conventional methods for the FilmArray® ME Panel in suspected meningitis/encephalitis cases across multiple Brazilian regions in 2025. This retrospective study included CSF samples from patients with clinical suspicion of meningitis or encephalitis admitted to hospitals in the Federal District and in five Brazilian states (São Paulo, Pará [Belém], Amazonas [Manaus], Minas Gerais, and Tocantins) during 2025. Samples were tested using the FilmArray® ME Panel according to the manufacturer’s instructions. Data were extracted from the laboratory information system and included detected targets, positivity rate, and TAT defined as CSF receipt-to-result release. When available, FilmArray® findings were compared with conventional microbiological methods (CSF culture) to assess agreement. A total of 78 CSF samples were analyzed. The FilmArray® ME Panel detected at least one target in 14.1% (11/78) of cases. Bacterial detections occurred in 6/11 (54.5%) and viral detections in 5/11 (45.5%) positive cases. Detected targets among positives were: varicella-zoster virus (27.3%, 3/11), Escherichia coli K1 (18.2%, 2/11), and 9.1% (1/11) each for Neisseria meningitidis, Listeria monocytogenes, human parechovirus, herpes simplex virus 1, and Haemophilus influenzae. One case showed dual bacterial detection (Haemophilus influenzae + Streptococcus agalactiae; 9.1%, 1/11). Among the six bacterial-positive samples, CSF culture was positive in 1/6, with culture TAT of 33 hours in the concordant case; the remaining bacterial-positive samples showed no growth (5/6; 83.3%). For positive FilmArray® results, receipt-to-release TAT was <4 hours in the fastest case, and overall TAT was variable (median 11.6 h, range 1.48–94.15 h). Among bacterial-positive cases, median TAT was 9.33 h (range 1.48–94.15 h), while viral-positive cases showed a median TAT of 29.0 h (range 2.21–43.2 h), consistent with workflow-dependent delays in some cases. In this multiregional retrospective cohort, the FilmArray® ME Panel provided etiologic identification in 14.1% of suspected meningitis/encephalitis CSF samples and demonstrated substantially shorter receipt-to-result turnaround than culture in a concordant bacterial case. The spectrum of detected pathogens included both bacterial and viral etiologies, with occasional co-detection. These findings support integrating multiplex molecular panels into diagnostic pathways for suspected central nervous system infections, particularly in urgent hospital settings, while emphasizing that realized TAT is sensitive to ordering and workflow practices.