Abstract: SA-PO0188
Double Trouble: A Patient with Light-Chain Amyloidosis and Apolipoprotein A-IV Amyloidosis
Session Information
- Onconephrology: MGRS, HSCT, Electrolytes, RCC, and More
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Conlon, Luke, University of Utah Health, Salt Lake City, Utah, United States
- Fitzgerald, Lindsey, University of Utah Health Huntsman Cancer Institute, Salt Lake City, Utah, United States
- Stephens, Carrie, US Department of Veterans Affairs, Salt Lake City, Utah, United States
- Godara, Amandeep, University of Utah Health, Salt Lake City, Utah, United States
- Revelo Penafiel, Monica Patricia, University of Utah Health, Salt Lake City, Utah, United States
- Abraham, Josephine, University of Utah Health, Salt Lake City, Utah, United States
Introduction
Renal amyloidosis is a disorder characterized by extracellular deposition of insoluble protein aggregates in the glomeruli, tubulointerstitium, or vasculature. Light chain (AL) amyloidosis caused by clonal plasma- or B-cells is the most frequent subtype of amyloidosis encountered in kidney disease. In contrast, apolipoprotein A-IV (AApoAIV) amyloidosis is a less well characterized form of acquired amyloidosis associated with renal and/or cardiac involvement. It presents with subtle, progressive decline in kidney function and is often confined to the kidney.
Case Description
A 79-year-old male with a history of T2DM presented with one year of lower extremity edema. Laboratory evaluation revealed a creatinine of 1.18 mg/dL, serum albumin 3.0 g/dL, and LDL 257 mg/dL with a 24-hour urine protein of 12 g. Serum immunofixation (IFE) revealed a faint lambda light chain band and serum free light chain assay showed elevated lambda light chains at 97.72 mg/L and abnormal K/L ratio of 0.22. Kidney biopsy demonstrated amyloid deposits within the glomerulus, interstitium, and arteriolar walls. Immunofluorescence showed weak staining for lambda light chains, suspicious for AL amyloidosis. Mass spectrometry was performed and detected both AL-type and ApoAIV type amyloid.
Hematologic evaluation included bone marrow biopsy, which showed 10% plasma cells with lambda light chain restriction, consistent with a plasma cell dyscrasia. Congo red stain showed possible amyloid deposition. Echocardiogram and PET/CT did not demonstrate signs of systemic involvement. The patient was initiated on treatment with daratumumab and CyBorD and has shown renal and hematologic response to therapy several months after treatment initiation.
Discussion
This patient presented with nephrotic syndrome and was found to have coexisting AL and AApoAIV amyloidosis. AApoAIV amyloid is characterized histologically by large medullary deposits and is clinically associated with progressive decline in kidney function with minimal proteinuria. The clinical presentation was most consistent with AL amyloidosis as the predominant pathogenic process with the patient having a favorable response to chemotherapy targeting AL amyloidosis. The coexistence of both AL and AApoAIV amyloidosis has not been reported and the implications for prognosis remains unclear.