Prospective Longitudinal Cohort Study of Vasculitis Patients

Who May Qualify: - Adult patients (age over 18 years), - Patients with vasculitis, as defined in the Chapel Hill International Nomenclature as revised in 2012, - Patients included at an active phase of the disease, either the initial flare or a relapse, - Patients who have been informed and have signed the consent - Pregnant and breastfeeding women may be included in the study, - Affiliated to a social security system (beneficiary or entitled person). Who Should NOT Join This Trial: - Refusal of consent or inability to obtain consent, - A patient who is insane or not entitled, for psychiatric reasons or intellectual impairment, to receive information about the protocol and to give willing to sign a consent form, - Patient under guardianship / curators - Patient on state medical assistance (AME) - Hemoglobin less than 7 g/dl at the time of sampling, - Hemoglobin level less than 9 g/dl at the time of sampling if the patient has respiratory or cardiovascular disease, - Patient weighs less than 18 kg. - Parallel participation in an interventional protocol is permitted. Always talk to your doctor about whether this trial is right for you.