Prospective Study of Different Biological Tests (Multiplate, ROTEM) in a Cohort of Patients Followed for Essential Thrombocytemia (ET)

Study Overview
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Brief Summary
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There is no prospective study published on the Essential Thrombocythemia and the correlation between this specific disease, its complications and the biological variations observed. The aim of this study is to demonstrate a correlation between biological tests of haemostasis, as Multiplate analyser and thromboelastometry (ROTEM) and the occurrence of clinical complications, thrombosis and/or haemorrhage, in order to determine if this biological tests could be biological prognostic factors

Official Title
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Prospective Study of Different Biological Tests (Multiplate, ROTEM) in a Cohort of Patients Followed for Essential Thrombocytemia (ET)

Conditions
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Thrombocythemia Essential

Intervention / Treatment
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* Biological: biological tests of haemostasis at each consultation (Multiplate, ROTEM, VASP)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult aged more than 18 years old Patient followed in consultation for an Essential Thrombocythemia at diagnosis or during the follow-up Collection of the informed consent Patient affiliated to Social Security Exclusion Criteria: Patients aged less than 18 years old Refusal of signature of the informed consent Patients under guardianship

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Patients with Essential Thrombocythemia<br>patients who come in consultation at diagnosis or during the follow-up for an Essential Thrombocythemia. They will have biological tests of haemostasis at each consultation (Multiplate, ROTEM, VASP) | Biological: biological tests of haemostasis at each consultation (Multiplate, ROTEM, VASP)<br>* Patients will have blood samples at each consultation (2 or 3 sampling tubes) in order to carry out systematically three biological tests<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of thrombotic complications | All thrombotic complications will be gathered by the investigators during the four months following the realization of Multiplate and ROTEM test | every 4 months, up to 18 months | 
| Occurrence of haemorrhagic complications | All haemorrhagic complications will be gathered by the investigators during the four months following the realization of Multiplate and ROTEM test | every 4 months, up to 18 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of thrombotic complications | All thrombotic complications will be gathered by the investigators during the four months following the realization of VASP test | every 4 months, up to 18 months | 
| Occurrence of haemorrhagic complications | All haemorrhagic complications will be gathered by the investigators during the four months following the realization of VASP test | every 4 months, up to 18 months | 
| Changes of tests results according to medical treatments | All modifications of medical treatments will be gathered at each consultation to analyse changes of biological tests results | every 4 months, up to 18 months | 
| Description of platelet physiopathology | Using a specific test of release of ATP to study the platelet physiopathology in Essential Thrombocythemia only for patients seen at diagnosis and naive of all medical treatment | the day of inclusion | 
| Description of platelet physiopathology | Using electronic microscopy to study the platelet physiopathology in Essential Thrombocythemia only for patients seen at diagnosis and naive of all medical treatment | the day of inclusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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haemorrhage, Essential thrombocythemia, Multiplate, ROTEM, thrombosis, Vasodilatator Stimulated Phosphoprotein (VASP)