Sepsis remains a major cause of death in developed countries. A better understanding of the mechanisms involved in the regulation of inflammatory and immune response of patients with severe sepsis is an important step that could open the way for new therapeutic approaches.

Inclusion Criteria:

• Patient ≥18 years old

• Patient with two criteria of systemic inflammatory response syndrome and one of the four following criteria within 24 hours of hospitalization in ICU:

  • Lactate >4 mmol/L
  • PaO2 / FiO2 <200 in the presence of lung disease as infectious source
  • Vasopressor: adrenaline or noradrenaline ≥0.25 µg/kg/min for at least 6 hours to maintain a systolic blood pressure ≥90 mmHg or mean arterial pressure ≥65 mmHg
  • Thrombocytopenia linked to sepsis with platelet count <100,000 / ml or a decrease ≤50% within 48 hours

Exclusion Criteria:

• Pregnancy
• progressive solid cancer
• HIV infection
• History of blood or inflammatory disease
• long-term immunosuppressive treatment
• Prior episode of Sepsis in the previous month
• Chronic Dialysis Patient
• Patient under guardianship
• Patient not affiliated with a social security system

Patient hospitalized in intensive care for sepsis evolving for less than 48 hours with two criteria of systemic inflammatory response syndrome