Evaluation of the Prognostic Value of Immature Platelet Fraction

Evaluation of the Prognostic Value of Immature Platelet Fraction in Septic Patients Admitted to Critical Care

Sepsis is a public health issue responsible for six million deaths worldwide each year. It is one of the leading causes of admission and morbidity and mortality in critical care. Its most severe form, septic shock, is responsible for a picture of multiple organ failure syndrome with a high mortality rate estimated at 38%. It appears important to identify routinely available and low-cost biomarkers to identify patients at risk of adverse outcomes.

In the pathophysiology of host defense against infection, coagulation plays a major role. In the most severe forms of sepsis, there is an activation of coagulation, particularly platelets, which can cause an alteration of microcirculation and contribute to organ failure. This mechanism is called thromboinflammation. The appearance of thrombocytopenia in sepsis is a risk factor for severity and intrahospital mortality. Immature (or reticulated) platelets are young platelets that have just been released by the bone marrow. They are more prothrombotic and hyperactive than more mature platelets. They are a good marker of thrombopoiesis and platelet renewal, and can be easily obtained routinely on a complete blood count. Several studies show that the immature platelet count and/or fraction (IPF) could be a useful tool for predicting the development of sepsis and its severity. It appears interesting to study these IPFs in patients with sepsis to identify them and implement more aggressive therapies to prevent adverse outcomes in these patients. To distinguish between sepsis and inflammation and validate this marker, it will be compared to an inflammatory group using patients who underwent cardiopulmonary bypass as part of cardiac surgery.

The main objective of this study is to investigate the potential impact of the immature platelet fraction on the prognosis at day 28 of patients admitted to critical care for sepsis or septic shock.

Inclusion Criteria:

• Any adult patient admitted to critical care for sepsis defined by a SOFA score > or = 2 or an increase of at least 2 points if there was organ dysfunction pre-existing to the infection.
• For the inflammatory control group, we will include adult patients who have required extracorporeal circulation for more than 1 hour for cardiac surgery.
• Patients who have read and understood the information letter and do not object to participating in the study
• Patients affiliated with a social security scheme
• Exclusion Criteria:
• Patient refusal
• Pregnant, parturient, or breastfeeding woman
• Person deprived of liberty by an administrative or judicial decision or person placed under judicial protection/guardianship or curatorship
• Person who does not understand or speak French
• Moribund
• Febrile aplasia
• Hematological diseases
• Decompensated cirrhosis
• Ongoing chemotherapy