B Lymphocyte Populations in the Pulmonary Microenvironment of Patients Under Mechanical Ventilation With or Without VAP (Ventilator-Associated Pneumonia)

Diagnosis of VAP relies on a set of non-specific clinical, biological, and imaging criteria. Understanding host-pathogen interactions and the mechanisms of deregulations leading to infection of pulmonary tissue appears essential. The aim is to qualitatively describe the B lymphocyte populations present in the pulmonary microenvironment of patients admitted to intensive care and requiring invasive mechanical ventilation

Inclusion Criteria: * Adult patients (≥18 years old), admitted to intensive care under mechanical ventilation for an estimated duration of at least 5 days. Exclusion Criteria: * Patients admitted for an infectious pneumonia or presenting with acute respiratory distress syndrome (ARDS). Patients in aplasia (leukocytes \< 0.5 gigal/L).