Abstract: TH-PO575
Recurrent Monoclonal Ig Associated C3GN Post Transplant
Session Information
- Trainee Case Reports - II
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Keetha, Narsimha R., university of alabama at birmingham, Birmingham, Alabama, United States
- Ong, Song Ching, University of Alabama of Birmingham, Birmingham, Alabama, United States
- Kumar, Vineeta, University of Alabama at Birmingham, Birmingham, Alabama, United States
Introduction
C3 glomerulopathy (C3GN) is one type of renal injury characterized by the predominant staining for C3 with absent or minimal staining for other immunoglobulin (Ig). Although the optimal treatment is unknown, success has been reported with B cell targeted chemotherapy. We describe a case of monoclonal Ig-associated C3GN recurring soon after transplant.
Case Description
A young woman with ESRD attributed to hypertension on hemodialysis for 7 years underwent a deceased donor kidney transplant in 2017. Creatinine (Cr) was 1.1 mg/dL with proteinuria of 0.35g/g at 1 week post-transplant. Within several weeks of transplant, she developed clinical nephrotic syndrome with Cr 2.5 mg/dL and proteinuria 4.3g/g. Renal allograft biopsy demonstrated a membranoproliferative glomerulonephritis (MPGN) on light microscopy. Immunofluorescence (IF) showed 2+ staining for C3. There was weak staining for IgM and C1q. Electron microscopy showed rare subendothelial electron dense deposits. Serum and urine were positive for a monoclonal IgG kappa with M spike of 0.64 g/dL. Records retrieved included a kidney biopsy in 2009 which showed MPGN. IF showed IgG2+, C3 2+, C1q 2+, and kappa 1+. A monoclonal IgG kappa was detected, but a bone marrow biopsy was negative for a plasma cell dyscrasia. On reaching ESRD in 2010, she transferred care and records were not forwarded for transplant evaluation.
Our patient underwent a second bone marrow biopsy that confirmed the presence of monoclonal plasma cells (0.2% of total). Workup for multiple myeloma was negative. She was commenced on cyclophosphamide, bortezomib, and dexamethasone. With treatment, proteinuria has improved to 2.2 g/g and renal function stabilized with a last follow-up Cr of 1.8.
Discussion
Our patient had a monoclonal gammopathy of renal significance (MGRS) which remained indolent for many years but caused recurrent disease rapidly after transplant. Successful treatment of monoclonal Ig associated C3GN in native kidney disease with chemotherapy has been described, but reports of treatment for recurrent disease post-transplant have been scant. In addition to chemotherapy, use of eculizumab has been reported to be successful. Following chemotherapy, our patient will be evaluated for an autologous stem cell transplant. Our case adds to the limited literature and awareness surrounding the diagnosis and treatment of this rare disease.