Abstract: TH-PO0809
Combined Presentation of Primary Membranous Nephropathy and Monoclonal Gammopathy of Unknown Significance
Session Information
- Glomerular Case Reports: Membranous, PGN, GBM, and More
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Habib, Nazia, Albany Medical Center, Albany, New York, United States
- Der Mesropian, Paul J., US Department of Veterans Affairs Veterans Health Administration, Albany, New York, United States
- Shaikh, Gulvahid G., US Department of Veterans Affairs Veterans Health Administration, Albany, New York, United States
Introduction
Learning Objectives:
Primary membranous nephropathy can exist with MGUS (monoclonal gammopathy of unknown significance)
Rarely monoclonal gammopathy can also lead to secondary membranous nephropathy
Importance of ruling out MGRS (monoclonal gammopathy of renal significance) in patients with primary membranous nephropathy
Case Description
We present a case of primary membranous nephropathy with coexisting MGUS diagnosed at the same time without evidence of MRGS on renal biopsy.
54-year-old male presents with 1 month history of weight gain, anasarca and hypoalbuminemia along with nephrotic range proteinuria. Clinical and Lab findings meeting criteria for nephrotic syndrome. Urinalysis showed no RBCs. Serum Creatinine of 1.2 mg/dl with corresponding eGFR of 70ml/min. Hemoglobin of 13.7g/dl, normal WBC count, HbA1c of 5.3. Negative HIV, hepatitis B and C, ANA, ANCA and normal complements. He had LDL of 310mg/dl, cholesterol 425mg/dl, Total protein 4g/dl and Albumin of 1.4 g/dl. INR 0.9, BNP was normal. 24-hour urine collection showed protein of 5.3 gram /24hr. PLA2R antibody titer was 142 RU/ml. Serum protein electrophoresis showed elevated free kappa light chain, normal lambda light chain, and elevated serum free K/L light chain ratio 47. Patient underwent renal biopsy, pathology consistent with primary membranous nephropathy with positive staining for PLA2R in biopsy. IF-glomeruli reveal diffuse and global granular capillary loop staining for igG3 93+),C3(3+),kappa(3+) and Lamda (3+)
Discussion
Primary membranous nephropathy can coexist with new diagnosis of MGUS. There is only a handful of case reports of secondary membranous nephropathy related to light chain disease. If deposition disease is concurrently present within the kidneys, it has been hypothesized that monoclonal deposits in the glomerular basement membrane or podocyte can serve as an antigen and contribute to the antibody response against PLA2R. MGUS has the potential to evolve into MGRS or a malignancy. There is a strong association of solid organ malignancy with secondary membranous nephropathy but the simultaneous occurrence of MGUS and primary membranous nephropathy is rare and unclear if simultaneous occurrence has any association between the two conditions vs a coincidental finding.