Maintaining or Stopping Immunosuppressive Therapy in Patients With ANCA Vasculitis and End-stage Renal Disease

Inclusion Criteria: * Age ≥ 18 years and ≤ 90 years * Patients affected by a GPA or MPA AAV with a renal injury * Patients with initial manifestation or relapse of AAV * Patients with ESRD, defined by a glomerular filtration rate estimated using the MDRD formula ≤15 mL/min or requirement for dialysis for more than 60 days * Patients with ESRD on native kidney * Patients who gave written informed consent for participation in the study * Patients with affiliation to the French social security system Exclusion Criteria: * Patients who experienced severe extra-renal disease due to AAV (intra-alveolar haemorrhage with blood oxygen saturation ≤ 85% on room air or ventilated, or central nervous system disease) in the last 12 months prior to inclusion * Patients with AAV-associated renal involvement (with active inflammatory lesions in kidney biopsy) diagnosed less than three months and receiving induction treatment with cyclophosphamide or rituximab or diagnosed less than 45 days for patients who have receveid only treatment based on steroid infusion without cyclophosphamide or rituximab * Patients who received maintenance immunosuppressive treatment for more than 6 months during the last 12 months * Patient with a diagnosis of vasculitis other than GPA or MPA * Patients with another immunologic systemic disease (Lupus, sarcoidosis…) Patients with active HCV, HBV or HIV infection * Patients with a history of serious viral infection (CMV, HHV8, etc.) in the 2 months prior to the inclusion, or severe uncontrolled chronic infection (tuberculosis, etc.) * Patients with uncontrolled cancer or hemopathy * Kidney transplant patient * Inability to understand and sign the informed consent * Pregnant women. * Women of child-bearing age without effective method of contraception * Age \< 18 years or \> 90 years. * Patients under guardianship or trusteeship.