Proliferative Glomerulonephritis with Monoclonal IgG Deposits Recurs or May Develop De Novo in Renal Allografts
A Albawardi, A Satoskar, S Brodsky, GM Nadasdy, T Nadasdy. The Ohio State University, Columbus, OH
Background: Proliferative glomerulonephritis with monoclonal IgG deposits (PGNmIgGD) is a recently recognized glomerular disease (JASN 20:2055, 2009). The glomerular deposits are mostly IgG3 kappa and, unlike in the usual forms of monoclonal immunoglobulin deposition disease, extraglomerular deposits do not occur. The light microscopy resembles membranoproliferative glomerulonephritis (MPGN) with variable degree of glomerular lobularity/nodularity. Recurrence or de novo PGNmIgGD in renal allografts has not been reported yet.
Design: We reviewed our renal biopsy files since 01/01/03 to identify patients with PGNmIgGD in native and transplant kidney biopsies. IgG subtype staining was performed in all biopsies by immunofluorescence on frozen sections.
Results: We identified 16 patients with PGNmIgGD (0.27% of our biopsies); 3 of them have been reported previously as part of a large series (JASN 20:2055, 2009). The morphology and clinical course was similar to the previous series. The patients were mostly Caucasian females (14), had IgG3 kappa deposits (14) and had a relatively slowly progressive renal disease with severe proteinuria. Only two patients had monoclonal IgG kappa spikes in the serum; no patient had myeloma. In 15 patients, the disease appeared in the native kidney. A 68-year-old female patient had de novo disease with glomerular IgG1 kappa deposits in a renal allograft 13 years post transplant (native kidney disease was polycystic kidney disease). The graft failed 16 months following the biopsy. One patient with glomerular IgG3 kappa deposits underwent renal transplantation three years after the diagnosis of PGNmIgGD in his native kidneys. He developed recurrent disease with similar glomerular IgG3 kappa deposits one year post transplant. The patient died of a heart attack 1 ½ year after the transplant biopsy. He had 8 to 13 g/24h proteinuria and serum creatinine levels between 1.5 and 2.0 mg/dl at and after the diagnosis of recurrent disease.
Conclusions: Ours is the first report describing the appearance of PGNmIgGD in renal allografts. The disease can be de novo or recurrent. The recurrent disease developed rapidly, causing heavy proteinuria. Although based on our series we cannot determine the risk of recurrence in an individual patient, it is probably high. Our cases provide further proof that PGNmIgGD is a distinct glomerular disease entity.
Category: Kidney (does not include tumors)
Monday, March 22, 2010 2:45 PM
Platform Session: Section H, Monday Afternoon