Abstract: SA-PO0790
Proteinuria Beyond Diabetes: A Rare Case of Chronic Lymphocytic Leukemia-Associated Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits and the Utility of Kidney Biopsy
Session Information
- Glomerular Diseases: Lupus Nephritis, Monoclonal Gammopathy-Related Disease, and Transplantation
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Bloch, Rosalyn, Corewell Health Farmington Hills Hospital, Farmington Hills, Michigan, United States
- Bernard, Alaina, Corewell Health Farmington Hills Hospital, Farmington Hills, Michigan, United States
- Schukow, Casey P., Corewell Health East, William Beaumont University Hospital, Department of Pathology, Royal Oak, Michigan, United States
- Biederman, Jason I., Corewell Health Farmington Hills Hospital, Farmington Hills, Michigan, United States
Introduction
Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) is a renal disease within monoclonal gammopathy of renal significance (MGRS), with an estimated biopsy incidence of 0.17–3.7% and a poor renal prognosis if untreated. Although chronic lymphocytic leukemia (CLL) is often managed with observation, CLL-associated PGNMID warrants therapy. We present a rare case of CLL-associated PGNMID with IgG lambda deposits, stressing the importance of evaluating sub-nephrotic proteinuria and recognizing renal indications for CLL treatment.
Case Description
An 82-year-old male with chronic hypertension and 3-year history of T2DM was referred to nephrology for sub-nephrotic proteinuria (Cr 0.96 mg/dL, albumin 3.9 g/dL, and UPC 2.07 g/g). Workup revealed IgM 817 mg/dL with hypocomplemententemia (C3 75 mg/dL, C4 5 mg/dL), prompting kidney biopsy demonstrating PGNMID with IgG lambda deposits. Hematologic workup identified CLL. Rituximab therapy improved UPC to 0.42 g/g with complement normalization.
Discussion
CLL-associated PGNMID is rare, with fewer than 100 cases reported. Unlike the typical IgG3-kappa pattern seen in PGNMID, our patient had IgG lambda deposits. As teaching points, proteinuria remains under-investigated, with most patients meeting referral criteria never seeing a nephrologist. This is especially concerning in sub-nephrotic range proteinuria where biopsy data shows primary glomerulonephropathies in over one-third of cases. Proteinuria in patients with T2DM is frequently attributed to diabetic kidney disease, potentially delaying recognition of alternative etiologies. Second, MGRS-related kidney injury can cause end-organ damage, necessitating therapy, even when CLL itself does not meet traditional treatment criteria. In conclusion, this case stresses the importance of evaluating proteinuria broadly and recognizing PGNMID as a renal indication for CLL-directed therapy.
IF IgG (top left, A); IF C3 (top middle, B); IF Lambda (top right, C); EM showing electron dense deposits in mesangial and subendothelial areas (arrows; bottom left and right, D and E)