Diagnostic accuracy of a host response test in suspected community-Acquired pneumonia during the COVID-19 era

Community-acquired pneumonia [CAP] is a leading cause of morbidity and mortality, often complicated by diagnostic uncertainty and antibiotic overuse. This study evaluated the MeMed BV® host-response test in adults with suspected CAP, using clinical management and molecular detection as reference standards. Among 744 patients presenting with suspected CAP at Haukeland University Hospital, Bergen, Norway (2019-2023), across three prospective studies, 453 were included in the present study. Patients were classified using: [1] clinical management [antibiotic timing/duration], and [2] molecular detection via BioFire® FilmArray Pneumonia Plus panel on lower respiratory tract samples. MeMed BV® testing was performed retrospectively on stored serum/plasma, categorising results as bacterial, viral, or equivocal. Healthy controls [n = 20] were also tested. Among 442 patients classified by clinical management, the MeMed BV® test demonstrated a positive percent agreement [PPA] of 90.0% (95% CI: 86.4-92.7) and a negative percent agreement [NPA] was 44.1% (95% CI: 34.4-54.2). In 370 patients classified by molecular testing, PPA was 88.2% (95% CI: 83.6-91.7) and NPA was 30.1% (95% CI: 20.8-41.4. Equivocal results occurred in 7.5%. The test agreed with clinical management in 96.1% of cases with no detected pathogen. None of the healthy controls had bacterial scores. CONCLUSION: MeMed BV® demonstrated high sensitivity in identifying bacterial infections but limited specificity in viral infections, notably SARS-CoV-2. It may aid early triage when combined with clinical and microbiological data. TRIAL REGISTRATION: ClinicalTrials.gov NCT04660084.