Research for Plasma Biomarkers Associated With Fatigue in Thrombocytopenic Patients

Inclusion criteria for patients (adults or minors): * Patients with constitutional or autoimmune (chronic or persistent ITP with last treatment administration ≥ 3 weeks) thrombocytopenia (platelet count \< 150×109/L) already diagnosed * patient not being treated and not receiving serotonin reuptake inhibitor (SSRI) or norepinephrine (SNRI) or antithrombotic treatments (antiplatelet or anticoagulant) in the 10 days prior to inclusion * affiliation to social security (beneficiary or assignee) * patient followed in consultation in one of the recruiting haematology departments * Patient (or parent) having received a detailed explanation of the research project and having consent by signing the consent form before any research-specific procedure Inclusion criteria for healthy volunteers: * Age- (± 5 years) and sex-matched healthy adult controls * Non-thrombocytopenic patients and not receiving antithrombotic, SNRI or SSRI therapy or if applicable, last treatment ≥ 10 days * affiliation to social security (beneficiary or assignee) * adults who received a detailed explanation of the research project and having consent by signing the consent form before any research-specific procedure Non inclusion criteria (adults and minors): * Adult patients under legal protection (guardianship or curatorship) Thrombocytopenic patients treated with antithrombotics, serotonin reuptake inhibitors (SSRIs) or noradrenaline reuptake inhibitors (SNRIs) * Minor patients weighing less than 20 kg Non inclusion criteria for healthy adult controls: * Healthy adult volunteers under legal protection (guardianship, curatorship or safeguard of justice). * Pregnant women