Sepsis is a medical emergency whose prognosis depends on the early identification of patients at risk of septic shock, but the tools available in the Emergency Department remain insufficient. Neutrophils, key players in immunothrombosis, show alterations detectable via cell fluorescence (e.g., NE-SFL), which are strongly correlated with the severity of sepsis and septic DIC. The FLAMES study will evaluate, from the time of admission to the Emergency Department, the relevance of neutrophil fluorescence as an early biomarker of severity, either alone or integrated into an AI model based on the multiparametric data from the SthemA 801, with comparison to the Sysmex XN. It aims to address an unmet clinical need: the immediate stratification of the risk of severe forms of sepsis. Hypothesis: higher initial fluorescence will identify patients at risk of organ failure, septic shock, or DIC.

Inclusion Criteria:

• Age ≥ 18 years
• Admission to the ED
• Suspected or proven infection defined by the prescription of antibiotic therapy within 24 hours following admission to the ED
• Collection of an EDTA blood sample as part of routine care
• Patient informed and has not expressed opposition

Exclusion Criteria:

• Pregnancy or breastfeeding
• Legal protection measure (guardianship, curatorship, judicial protection)

Adult patients admitted to the Emergency Department and undergoing routine blood sampling will be prospectively included. The cohort aims to evaluate early biomarkers for the prediction of sepsis or septic shock within 72 hours of admission. No additional procedures or interventions beyond standard care are performed.