Patients between 18 and 70 years of age

Patient affiliated to a health insurance scheme (beneficiary or beneficiary's beneficiary)

Patient able to understand the aims and risks of research

Patient having signed and dated an informed consent form

Patient for whom the diagnosis of at least one of the following pathologies has been confirmed:

Systemic lupus erythematosus meeting ACR/EULAR 20195 classification criteria.

Systemic scleroderma meeting ACR/EULAR 20136 classification criteria.

ANCA vasculitis according to EULAR/ACR 2022.7-9 classification criteria.

Inflammatory myositis according to EULAR/ACR 201710 classification criteria.

Gougerot-Sjögren syndrome according to EULAR/ACR 2016 classification criteria11.

Rheumatoid arthritis according to ACR/EULAR 201012 classification criteria.

ROLE of PLATELETS in the PATHOPHYSIOLOGY of SYSTEMIC LUPUS