Predictive factors of renal recovery and end-stage kidney disease in patients with severe anca-associated vasculitis with glomerulonephritis

Background and Aims 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. Method A retrospective cohort study on MPO- or PR3-ANCA positive patients with AAV (MPA or GPA) and ESKD at presentation. Renal recovery, dialysis discontinuation and maintenance in ESKD after standard remission-induction, with or without the use of PLEX were compared. Results We analyzed 166 patients with biopsy proven active kidney involvement and eGFR <15mL/min/1.73m2 at the time of AAV-GN 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, SCr at diagnosis and minimal or mild chronicity changes. We analyzed 71 patients who started dialysis with or without PLEX within 4 weeks from AAV-GN diagnosis. The predictors for dialysis discontinuation were minimal chronicity changes in kidney biopsy at the time of diagnosis (OR 6.138, [95%CI 1.389-27.118],p = 0.017) and focal glomerular involvement (OR 5.017,[95%CI 1.287-19.567],p = 0.020). Predictors for maintenance in ESKD at 12 months included higher serum creatinine (SCr) at the time of diagnosis (IRR 1.086, [95%CI 1.005-1.173],p = 0.037), 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 maintenance 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.