Abstract: TH-PO0880
Renal AA Amyloidosis in a Patient with Urothelial Carcinoma Treated with Avelumab: A Clinical Case Report
Session Information
- Glomerular Case Reports: Potpourri
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Zinoveev, Maria Agustina, Universidad de la Republica Facultad de Medicina, Montevideo, Montevideo Department, Uruguay
- Parnizari, Paula, Universidad de la Republica Facultad de Medicina, Montevideo, Montevideo Department, Uruguay
- Ottati, Gabriela, Universidad de la Republica Facultad de Medicina, Montevideo, Montevideo Department, Uruguay
- Boggia, Jose, Universidad de la Republica Facultad de Medicina, Montevideo, Montevideo Department, Uruguay
Introduction
AA amyloidosis is a rare disorder, mostly secondary to inflammatory diseases and characterized by overproduction of serum amyloid A (SAA) by the liver, that results in the aggregation of amyloid into cross-β-sheet fibrillar deposits of amyloid. Kidney is the most common organ involved by systemic AA amyloidosis.
Case Description
59 y.o female with past medical history of urothelial carcinoma of right ureter with hydronephrotic pouch of the right kidney and lymph node involvement diagnosed 2 years ago. Initially treated with Gemcitabine and Cisplatin, 4 months ago, started avelumab maintenance therapy, discontinued 1 month ago. Previously avelumab, serum creatinine (sCr) was 1.3 mg/dl with normal urine sediment. In February of 2025 she was presented with rapidly progressive kidney injury and nephrotic syndrome (NS). Laboratory findings show sCr 9.7 mg/dl, hypoalbuminemia 2.3 g/dl and urine protein-to-creatinine ratio of 13 g/g. Urine electrophoresis informed nonselective proteinuria (50% albumin, 50% other globulins). Abdomen CT had no changes. C3:95 mg/dl C4:38mg/dl. AntiPLA2R antibodies: negative. Blood electrophoresis without monoclonal peak. We started intermittent hemodialysis (HD) and glucocorticoids empirically. In the absence of renal functional recovery (HD dependent) and severe sustained NS in a patient with oncological pathology treated with immune checkpoint inhibitors (ICI), we decided to perform kidney biopsy. Renal AA amyloidosis was confirmed by histopathological results (Figure 1).
Discussion
This is the first case report of renal AA amyloidosis in a patient under treatment with avelumab and active cancer. ICI are a cornerstone in the management of many oncological disorders achieving clinical success. Adverse effects are increasingly reported because of its use is in expansion. Renal toxicity is described as 1-2% and the most common pathological finding is acute interstitial nephritis. Recently AA amyloidosis was reported in 3 cases related to ICI but with cancer remission. In this case there is a relationship between initiation of avelumab and renal impairment, however cancer was not dormant.