Abstract: PO1954
Isolated ANCA Renal Arteritis
Session Information
- Glomerular Diseases: Clinical, Outcomes, and Trials - 3
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Shah, Ishan, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
- Messias, Nidia Cordeiro, Arkana Laboratories, Little Rock, Arkansas, United States
- Siddiqui, Muhammad Ahmar, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
- Combs, Sara, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
- Teixeira, J Pedro, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
Introduction
Vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) usually causes acute kidney injury (AKI) through crescentic glomerulonephritis (GN). Renal ANCA arteritis without GN is often accompanied by prominent interstitial nephritis (IN). We present a case of AKI due to ANCA renal arteritis without significant GN or IN.
Case Description
An 84-year-old woman with hypertension, chronic kidney disease [baseline creatinine (Cr) 1.6 mg/dL], and prior right nephrectomy for renal cell carcinoma presented with nausea and anorexia. She was admitted the prior month for pyelonephritis and AKI and discharged to a rehab facility. On return, her serum Cr was 4.9. She was readmitted and started on hemodialysis. Urine microscopy was consistent with acute tubular injury (ATI), but also showed non-glomerular hematuria which persisted on several UAs. Urine protein was 2.1 g/g Cr. Both p-ANCA (1:1280) and MPO (>8 AI) were strongly positive. She was given IV corticosteroids and renal biopsy was obtained [Figure]. She was evaluated by rheumatology and felt to have renal-limited disease. She was treated with plasma exchange followed by rituximab, but a week later she opted to stop dialysis and transition to comfort measures and she died 2 days later.
Discussion
Most patients with AKI from ANCA-associated vasculitis will have GN, often crescentic. Extraglomerular features on biopsy of ANCA disease are common and include IN and arteritis/arteriolitis, but often parallel the activity of glomerular disease. Prior case reports of ANCA renal disease without GN have featured prominent IN with or without arteritis/arteriolitis. This case of marked necrotizing arteritis, minimal IN, and absent GN represents a rare phenotype of ANCA renal disease.
Biopsy yielded 31 glomeruli; 7 were globally sclerotic and the rest were without crescents, necrosis, or endocapillary hypercellularity (panel A, silver stain, 400x). IF was negative. Diffuse ATI was seen, with moderate (35%) interstitial fibrosis and mild patchy mononuclear inflammation limited largely to areas of fibrosis. Multiple arteries and few arterioles exhibited fibrinoid necrosis, including focal areas of transmural necrosis and circumferential arteritis (panels B & C, H&E, 400x).