Clinico-biological Collection to Investigate the Physiopathology of Systemic Autoimmune Diseases

This study builds a biological sample bank (biobank) from patients with rare systemic autoimmune diseases — conditions like lupus, scleroderma, and myositis, where the immune system attacks the body's own tissues. By collecting blood and tissue samples over time, researchers can study the disease mechanisms and test new therapies. You may be eligible if: - You are 6 years or older - You have a confirmed or probable rare systemic autoimmune disease (such as lupus, scleroderma, or myositis) - You have an atypical or complex presentation of an autoimmune disease - You are receiving or being considered for a new or innovative therapy You may NOT be eligible if: - You have known anemia with hemoglobin below 10 g/dL - You are under legal guardianship or protected supervision - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.