Abstract: FR-PO1157
Recurrent Type 1 IgM Cryoglobulinemic Membranoproliferative Glomerulonephritis (MPGN) After Kidney Transplantation
Session Information
- Transplantation: Clinical - Transplant Access, Recipient Evaluation, Living Donors, Pregnancy, and More
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Authors
- Alsaedi, Zainulabdeen S., Washington University in St Louis, St. Louis, Missouri, United States
- Gomide Almeida, Guilherme, Washington University in St Louis, St. Louis, Missouri, United States
- Ikrai, Hamza, Washington University in St Louis, St. Louis, Missouri, United States
- Messias, Nidia Cordeiro, Washington University in St Louis, St. Louis, Missouri, United States
- Murakami, Naoka, Washington University in St Louis, St. Louis, Missouri, United States
- Merzkani, Massini, Washington University in St Louis, St. Louis, Missouri, United States
Introduction
We report a rare case of recurrent Type I IgM cryoglobulinemic MPGN in a kidney transplant recipient.
Case Description
A 72 yr old woman with ESRD from type 1 IgM κ cryoglobulinemic MPGN due to Waldenström macroglobulinemia was treated with melphalan/rituximab/steroids (partial response), then ibrutinib, achieving a 4 yr complete response but ultimately progressed to ESRD ~15 yrs after diagnosis.
She underwent a preemptive DDKT with basiliximab induction and TAC/MPA/Pred maintenance. Early post txp course was stable with preserved allograft function and no proteinuria or cryoglobulinemic flare. She was monitored with serial sFLC, SPEP, and annual BM exams for WM stability.
Two yrs later, she developed new HTN and AKI, with imaging concerning for TRAS. Labs showed SCr 2.34 mg/dL (baseline 1.22), UPCR 2.665 g/g, and K/L ratio 12.26. BM bx revealed 10% CD5/CD10 B cell lymphoma with plasmacytic features (↑ from <5%) and positive cryoglobulins. Allograft bx confirmed recurrent type 1 cryo MPGN with IgM κ–dominant IC deposition, consistent with WM related renal recurrence.
She was treated with rituximab, bendamustine, and steroids, improving SCr to 1.8 mg/dL. Renal angiogram showed no hemodynamically significant TRAS.
Discussion
Renal involvement in WM is recognized but remains poorly characterized, and it significantly influences prognosis and the need for clone directed therapy. Kidney transplantation in WM is controversial due to limited data and relapse risk under immunosuppression, but it may be appropriate in carefully selected patients who achieve deep hematologic responses.
Ongoing multidisciplinary follow up with SPEP, sFLC, and bone marrow monitoring is essential, along with individualized management and a low threshold for kidney biopsy.
A: MPGN with PAS +ve hyaline pseudothrombi in glomerular and peritubular capillary lumens. B & C: IF showing IgM κ–restricted staining within the pseudothrombi. D: EM demonstrating numerous cryoglobulin deposits in glomerular capillary lumens.