Abstract: PO1818
A Case Series of Proliferative Glomerulonephritis with Monoclonal Immune Deposits
Session Information
- Glomerular Diseases: IgA, C3G, and FSGS
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Koshti, Deepa Ajay, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Saxena, Ramesh, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
Introduction
Monoclonal gammopathy of renal significance (MGRS) comprises B-cell and plasma-cell clonal proliferative disorders that do not require treatment for the clonal disease but produce nephrotoxic monoclonal immunoglobulins (mIg) that elicit a variety of kidney manifestations. One such presentation is proliferative glomerulonephritis associated with monoclonal immune deposits (PGNMID), typically presenting as membranoproliferative glomerulonephritis (MPGN) and non-organized glomerular mIg deposits. We describe 3 unique cases of PGNMID from our institution.
Case Description
Case-1: A 16-year old female presented with abdominal pain, gross hematuria, nephrotic proteinuria, edema and normal renal function. Protein electrophoreses and bone marrow (BM) biopsy were unremarkable. Kidney biopsy showed MPGN with monoclonal IgG3 lambda deposits. She had inadequate response to B or plasma cell targeted therapies but responded very well to multitargeted therapy (mycophenolate+tacrolimus) achieving complete response.
Case-2: A 39-year old woman with history of antiphospholipid syndrome and 2 miscarriages developed persistent nephrotic proteinuria after uncomplicated third pregnancy. Kidney biopsy showed membranous glomerulopathy with mesangial hypercellularity and monoclonal IgG3 lambda deposits. BM biopsy and protein electrophoresis were unremarkable. She had partial response to rituximab. She is currently being treated with plasma cell targeted therapy with good response.
Case-3: A 28-year old male with nephrotic proteinuria found on routine examination. Further evaluation showed unremarkable BM biopsy and protein immunofixation. Kidney biopsy showed mesangial hypercellularity and monoclonal-IgG1 kappa deposits. He is currently being treated with rituximab.
Discussion
PGNMID is a subset of MGRS with variable histologic pattern and histological features of immune complex glomerulonephritis; however, the immune deposits are monoclonal and are seldom associated with serum M-spike. Our patients were younger than those reported in literature and had variable histologic patterns. None had M spike or clonal B or plasma cells. The response to treatment was variable. Two patients showed no response to B-cell depleting therapy. One patient did not respond to plasma-cell directed therapy, but the other did. The third patient is currently receiving B-cell depleting therapy.