Predictive Factors of Renal Recovery and Progression to End-Stage Kidney Disease in Patients with ANCA-Associated Vasculitis with Severe Kidney Disease

Introduction A significant number of patients with anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis (AAV) with glomerulonephritis (AAV-GN) still progress to end-stage kidney disease (ESKD, eGFR<15mL/min/1.73m2) despite advances in remission-induction treatment. Methods A retrospective cohort study on MPO- or PR3-ANCA positive patients with AAV (MPA or GPA) and eGFR<15 ml/min/1.73 m2 or ESKD at presentation. Renal recovery, dialysis discontinuation and persistence of end-stage kidney disease (ESKD) after standard remission-induction, with or without the use of PLEX were analyzed. Results We analyzed 166 patients with biopsy proven active AAV-GN and eGFR <15mL/min/1.73m2 at the time of diagnosis. Patients received glucocorticoids with CYC (n=84) or with RTX (n=72) for remission-induction, and 49 also received PLEX. The predictors for renal recovery were erythrocyte sedimentation rate, serum creatinine (SCr) at diagnosis and minimal or mild chronicity changes. We further analyzed 71 patients who started dialysis with or without PLEX within 4 weeks of AAV-GN diagnosis. The predictors for dialysis discontinuation were minimal chronicity changes in kidney biopsy at diagnosis (OR=6.138,[95%CI,1.389-27.118],p=0.017). Predictors for persistence of ESKD within 12 months included higher serum creatinine (SCr) at diagnosis (IRR=1.086,[95%CI,1.005-1.173],p=0.037), and moderate (IRR=3.797,[95%CI,1.090-13.225],p=0.036), or severe chronicity changes in kidney biopsy (IRR=5.883,[95%CI,1.542–22.439],p=0.009). Conclusion In our cohort, kidney recovery, dialysis discontinuation, and persistence of ESKD in patients with AAV-GN and eGFR<15mL/min/1.73m2 depended on SCr and histologic findings on kidney biopsies at the time of diagnosis and was not affected by the addition of PLEX.