Pneumonia Direct Pilot

This is a prospective, observational, diagnostic, feasibility study to determine the accuracy of pathogen- and host-directed testing for the diagnosis of VAP. Newly intubated adult patients admitted to the ICU will be assessed for eligibility around the time of intubation according to the inclusion/exclusion criteria. Screening and consent can occur any time within 48 hours of a patient being intubated. Between 48 and 60 hours after intubation, eligible participants will have blood drawn and dedicated research aliquots from SOC ETS samples retrieved. The dedicated research aliquots from SOC ETS samples will be obtained simultaneously with routine sampling for microbiologic testing or, when this is not possible, during routine suctioning as a part of standard airway care. Collection of other clinical data may occur 24 to 72 hours after intubation.

Participants will be followed daily for a clinical change for up to 14 days from the time of intubation. Clinical change is defined as a clinical suspicion of new-onset VAP that prompts the collection of lower respiratory tract secretions for routine microbiologic testing and initiation, continuation, or modification of antibiotic therapy for a pneumonia indication.

Participants who experience a clinical change will have additional blood samples drawn and dedicated aliquots of the sample retrieved from standard-of-care ETS procedures. Additionally, if available, leftover bronchoalveolar lavage (BAL) will be reclaimed, and respiratory and blood bacterial isolates will be obtained from SOC cultures. Participants will be followed through the diagnosis of clinical change and finalization of all local microbiological and radiological results obtained as a part of usual care. Clinical data will be recorded through medical record review.

Participants who do not experience a clinical change will be followed through extubation, ICU discharge, death, or for up to 14 days after intubation - whichever comes first. Participants who do not have a clinical change will not undergo additional sample collection.

Clinical change events will be used to assess whether the participant meets the clinical case definition (FDA criteria) for VAP: VAP-positive (VAP+) or VAP-negative (VAP-) categories will be obtained by an algorithm linked to the eCRF data. The VAP clinical case definition will be adjudicated against the participants' clinical data and microbiological evidence and the certainty of the VAP diagnosis will be classified as follows: Prove, Probable, Possible VAP, or No VAP. Every participant with a clinical change will be assessed for the presence of an extrapulmonary infection. Extrapulmonary infection will be classified as follows: Proven, Possible, or No Infection.

Evaluable participant specimens will be sent to a central laboratory for distribution to the testing centers that will perform the index testing. This study will compare pathogen-directed tests and host biomarker tests. Pathogen-directed tests detect and identify the most common causes of bacterial pneumonia, while host biomarker tests assess the host's immune response to infection. Testing centers will be blinded to whether the samples were collected at baseline or clinical change. Neither the study sites, participants, nor adjudicators will receive the results from the index testing.