Abstract: TH-PO644

Proliferative Glomerulonephritis with Monoclonal IgG Deposits in a Heart Transplant Patient with Hypogammaglobulinemia

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Scott, Jennifer, Mayo Clinic, Phoenix, Arizona, United States
  • Keddis, Mira T., Mayo Clinic, Phoenix, Arizona, United States
Background

We report a case of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) in a heart transplant recipient with hypogammaglobulinemia.

Methods

A 70 year-old man status post heart transplantation 4 years prior presented with peripheral edema, new onset hypertension, rising creatinine(creatinine 2.7 mg/dL), hypoalbuminemia (3.1 g/dL), hematuria and nephrotic proteinuria (7.7 g/24Hr) . Baseline chronic kidney disease (creatinine 1.5-1.9 mg/dL) was attributed to immunosuppression with calcineurin inhibition. Kidney biopsy revealed membranoproliferative glomerulonephritis with monoclonal IgG3 kappa deposit. Despite persistent absolute hypogammaglobulinemia, serum IgG3 levels were normal. Bone marrow biopsies at diagnosis, and 4 years later were both negative. No monoclonal spike was detected on serum or urine protein electrophoresis with immunofixation and free light chain ratio was normal during follow-up. He was initially treated with 6 months course of cyclophosphamide and tapering prednisone and mycophenolate mofetil was held during that time. He achieved partial remission with resolution of hematuria, normalizaton of serum albumin and reduction in proteinuria by ≥50% (2.9 g/24Hr) and creatinine nadir was 1.6 mg/dL. Four months after cessation of treatment, he suffered renal relapse with creatinine peak at 3.8 mg/dL and 7g/24 Hr proteinuria. He was treated with two doses of rituximab and tapering dose of prednisone and IgG3 levels nadired to 28.6 mg/dL (normal reference 18.4-106 mg/dL). Creatinine plateaued at 3.0 mg/dL with mimal improvement to proteinuria . Progressive renal failure developed and he was commenced on dialysis 31 months after diagnosis.

Conclusion

We describe the first case of PGNMID post heart transplant, despite immunosuppression and chronic hypogammaglobulinemia. We hypothesize that treatment failure was due to persistently normal IgG3 serum levels and absence of an identified clone for targeted therapy.