Year: 2026
Type: article
Study design: Case Report
Abstract: Background: Light chain (AL) amyloidosis is typically associated with plasma cell dyscrasias but can rarely arise from low-grade B-cell non-Hodgkin lymphoma. Renal involvement may present with nephrotic-range proteinuria, acute kidney injury, edema, anasarca, and hypoalbuminemia. Recognizing lymphoma-associated AL amyloidosis is essential because diagnosis requires tissue confirmation, and treatment must target the underlying clonal B-cell disorder. Case: We report a rare case of severe renal AL amyloidosis in a patient with known low-grade B-cell non-Hodgkin lymphoma previously treated with rituximab. The patient presented with witnessed syncope, progressive peripheral edema, anasarca, and hypotension. Initial evaluation showed acute kidney injury with nephrotic-range proteinuria, including a urine protein-to-creatinine ratio greater than 10 g/g. Workup for autoimmune, infectious, and malignant causes of proteinuric kidney disease revealed positive hepatitis C antibody, mildly elevated serum lambda free light chains, a mildly decreased kappa-to-lambda ratio, and serum immunofixation positive for an IgM monoclonal lambda gammopathy. Renal biopsy demonstrated severe AL amyloidosis with predominant renal involvement. Bone marrow biopsy showed low-grade B-cell non-Hodgkin lymphoma involving 85% of the marrow, with CD20-positive immunophenotyping. Conclusion: This case highlights a rare presentation of renal AL amyloidosis secondary to low-grade B-cell non-Hodgkin lymphoma. Persistent nephrotic-range proteinuria in patients with B-cell lymphoma, particularly with IgM lambda monoclonal gammopathy, should prompt evaluation for amyloidosis with renal biopsy and hematologic assessment.
Source: Frontiers in Nephrology
Authors: Alex Matthaeus, David Thomas, Hakan R. Toka
Institution: HCA Healthcare
Language: English
Subfield: Internal Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,353
OpenAlex ID: W7220677653