Abstract: TH-PO680
Rare Coincidence or Secondary Process: Membranous Nephropathy with ANCA-Associated Vasculitis
Session Information
- Glomerular Diseases: Case Reports - 1
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Al-yacoub, Leen, Cleveland Clinic, Cleveland, Ohio, United States
- Herlitz, Leal C., Cleveland Clinic, Cleveland, Ohio, United States
- Mehdi, Ali, Cleveland Clinic, Cleveland, Ohio, United States
Introduction
Membranous nephropathy (MN) is reported to occur in ANCA-associated vasculitis (AAV) and is usually thought of as secondary. We hereby contrast two cases with AAV both with membranous features one being PLA2R positive suggesting a primary disease process.
Case Description
Case 1: A 70-year-old man with hypertension and chronic sinusitis presented with worsening nasal symptoms, fatigue, poor appetite, and arthralgias. He had severe acute kidney injury requiring dialysis. He had positive C-ANCA/ PR3 antibodies with hematuria and nephrotic-range proteinuria on urinalysis. Kidney biopsy confirmed pauci-immune necrotizing crescentic glomerulonephritis but also showed prominent membranous nephropathy features. Serologic PLA2R testing was negative along with negative tissue PLA2R and Exostosin 1/2 staining. Patient was treated with pulse steroids, plasmapheresis, and oral cyclophosphamide and was able to be liberated from dialysis (Creatinine nadir: 1.2 mg/dL). Proteinuria also trended down from UPCR 7.9 to 3.9 g/g. Due to concern for relapse 3 months into treatment, he was switched over to Rituximab. Remission was achieved after 7 months. Now 2 years after starting rituximab, patient remains in remission (creatinine 1.17mg/dL, UPCR 0.3g/g).
Case 2: A 68-year-old female with hypertension and type 2 diabetes presented with generalized edema. She was found to have hematuria, proteinuria, and AKI (creatinine 1.1 mg/dL, baseline 0.7mg/dL). Albumin was 0.9 g/dL with proteinuria of 5.1 g/day. P-ANCA/MPO was positive with kidney biopsy showing pauci-immune crescentic glomerulonephritis along with prominent membranous features. Serologic PLA2R was positive. Patients was treated with pulse steroids and rituximab with serologic and clinical remission within 8 weeks. 5 years after diagnosis patient remains in complete remission (creatinine: 0.68 mg/dL, no hematuria or proteinuria).
Discussion
These cases highlight that MN can occur in the context of AAV. Whether the MN is secondary to AAV is not clear but the PLA2R positive case suggests a seperate primary disease. This patient’s presentation with a primarily florid nephrotic syndrome with a mild AKI also suggests that. Rituximab based therapy resulted in remission of both diseases in both cases.