Value of Flow Cytometry in Infectious Point of Care: Feasibility Study

The purpose of this project is to validate the diagnostic orientation properties of two new biomarkers (CD64, CD169) for patients with infectious syndromes arriving in emergency departments. This prospective observational study will focus on the quantification of these biomarkers on a hematology tube background (Pr Morange laboratory) without modifying the usual diagnostic and therapeutic procedures. The results of these assays will be compared with the diagnoses made at the end of treatment in order to determine their sensitivity and specificity. This study is the preliminary study, necessary to determine the detection characteristics of these biomarkers.

The detection and characterization of infectious events is a major challenge for emergency medicine. Thus the possibility of quickly attributing an infectious origin to a febrile and/or inflammatory syndrome makes it possible to treat and refer the patient quickly. In addition, the ability to distinguish bacterial etiology from viral etiology provides a valuable additional indication for the clinician. This of the upmost importance for fragile populations such as elderly patients and in epidemic conditions such as influenza. A new rapid diagnostic guidance solution is proposed by the Beckman Coulter Laboratory with the simultaneous assay of two biomarkers, one allowing the detection of a viral infectious process (CD169), the other of a bacterial infectious process (CD64). The combination of these two biomarkers, measured in 12 minutes by a new generation assay and flow cytometer, represents an opportunity for emergency services. To date, there is no study on the validation of this diagnostic orientation method. We propose to carry out a prospective, observational, non-interventional feasibility study to compare the results of these measurements with the usual diagnostic criteria combining the clinical signs, infectious testing, and biological data.