Abstract: FR-PO684
Vascular Renal Amyloidosis with Waldenstrom Macroglobulinemia (WM)
Session Information
- Electrolytes and Cancer Trainee Case Reports
November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1500 Onco-Nephrology
Authors
- Hasan, Shamir, Zucker School of Medicine at Hofstra Northwell, Great Neck, New York, United States
- Wanchoo, Rimda, Zucker School of Medicine at Hofstra Northwell, Great Neck, New York, United States
- Bijol, Vanesa, Zucker School of Medicine at Hofstra Northwell, Great Neck, New York, United States
- Jhaveri, Kenar D., Zucker School of Medicine at Hofstra Northwell, Great Neck, New York, United States
Introduction
Several kidney diseases have been associated with WM; they include lymphoplasmacytic lymphoma infiltration, immunoglobulin light chain (AL) amyloidosis and cryoglobulinemic glomerulonephritis. AL amyloidosis classically presents with nephrotic syndrome. We present a rare case of renal vascular AL amyloidosis in a patient with WM
Case Description
A 82-year-old white woman with history of WM presented with worsening kidney function. Nine years prior, she was diagnosed with WM and was treated with Bendamustine and Rituximab for 6 monthly cycles and then Rituximab maintenance for 2 years. She remained stable for six years. Over the last year, she was noted to have worsening anemia, rising serum creatinine from 1.3 mg/dl to 1.8 mg/dl and new onset of subnephrotic range proteinuria (1 gm/day). Her urinalysis did not reveal any blood or dysmorphic RBC. In addition, for several months, her blood pressure was harder to control. At baseline, her serum immunoglobulin free light chain ratio (Kappa/Lambda) was close to 9 and had risen to 45 at the time of presentation. Her immunofiixation was positive for IgM and IgG kappa. Physical exam was remarkable for a BP of 170/90 mm hg and trace lower extremity edema. Her serological work up was negative except for a low C4 (8 mg/dl). A kidney biopsy was performed which revealed significant non-specific chronic injury, with global glomerulosclerosis and tubulointerstitial scarring in about 50% of cortex. The better preserved glomeruli showed signs of hypoperfusion, but there was no amyloid, other paraprotein deposition, or hypercellularity in any of the glomeruli. Amyloid deposition, characterized by positive Congo red stain, was noted in a single arcuate artery with perivascular tissue involvement. Immunofluorescence revealed equal kappa and lambda staining on frozen tissue, but on paraffin sections, kappa staining was positive in the involved artery. Electron microscopy did not reveal amyloid fibers in the glomeruli. Based on these results, a diagnosis of WM associated renal vascular amyloidosis was made and she was started on treatment with bortezomib and rituximab and is currently doing well
Discussion
In a patient with WM presenting with kidney dysfunction and or proteinuria, vascular amyloidosis involving only the large vessels should also be considered in the differential diagnosis.