Abstract: SA-PO184
Acute Tubulointerstitial Nephritis with Membranous Nephropathy in a Patient with Newly Diagnosed Waldenstrom Macroglobulinemia
Session Information
- Onconephrology: Kidney Outcomes during Cancer Treatment and Nephropathies
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Wongmat, Napat, Navamindradhiraj University, Bangkok, Thailand
- Suphatheerawatr, Nitcha, Navamindradhiraj University, Bangkok, Thailand
- Kongpanvijit, Oraphan, Navamindradhiraj University, Bangkok, Thailand
- Jaturapisanukul, Solos, Navamindradhiraj University, Bangkok, Thailand
Introduction
Waldenstrom's macroglobulinemia (WM) is a rare B-cell lymphoproliferative neoplasm characterized by monoclonal immunoglobulin M (IgM) production. Renal involvement in WM is uncommon, often presenting as monoclonal-related kidney diseases like amyloidosis and cryoglobulinemia. Here, we report a rare case of WM associated with acute tubulointerstitial nephritis (ATIN) and membranous nephropathy (MN).
Case Description
A 62-year-old Thai woman was referred for rapid declining kidney function. 1 month prior to presentation, she had generalized edema, fatigue, and foamy urine. She had no prior medical history and was previously active. Physical examination revealed anemia, hepatosplenomegaly, and signs of volume overload. Laboratory results showed a serum creatinine level of 10.9 mg/dL and urine protein of 6 g/day without active urine sediment. Serum protein electrophoresis demonstrated IgM kappa monoclonal gammopathy. A bone marrow biopsy was consistent with lymphoplasmacytic lymphoma. Kidney biopsy findings included ATIN with B-cell lymphoma infiltration. Immunohistochemistry showed heavy interstitial staining for CD20+ and kappa light chain restriction. Electron microscopy revealed numerous subepithelial electron-dense deposits consistent with membranous nephropathy. The patient received a CHOP regimen, which improved the anemia; however, kidney function did not recover.
Discussion
In this case report, we describe a previously healthy woman presenting with rapidly progressive kidney function decline as the initial manifestation of her WM. Kidney pathology revealed ATIN due to lymphomatous infiltration and MN.
Light microscopy, immunohistochemistry for CD20+ shwoed acute tubulointerstitial nepritis from lymphomatous infiltration and electron microscopy show numberous subepithelial electron deposit.