Multicentric Castleman's disease with renal amyloidosis and mesangial proliferative glomerulonephritis: a case report.

Renal involvement is a significant complication of multicentric Castleman's disease (MCD) and various glomerular involvements have been reported. A 56-year-old Chinese woman presented with proteinuria and skin rash, with lymphadenopathy and hypergammaglobulinemia. Lymph nodes and skin biopsy proven the case was multicentric CD with plasma cell pathological pattern. The renal biopsy was performed and six glomeruli were observed and two of these showed global sclerosis. Moderate increasing of mesangial matrix with mesangial cell proliferation were seen in every glomerulus. In addition, one-segmental sclerosis accompanied by adhesion of the Bowman's capsule was revealed. Two of the glomeruli had crescents formation. Under immunofluorescence microscopy, immunofluorescence for anti-IgA, IgM, C3, C1q and FRA showed coarse and fine granular depositions along capillary walls and sparsely in the mesangium. Staining for anti-IgG was negative. Under electron microscopy revealed indiscriminate amyloidal deposits in glomerular basement membrane. The foot process of glomerular podocytes was fusion. Moderate increasing of mesangial matrix and mesangial cell proliferation were found. Subsequently, she was successfully treated with prednisone combined with cyclophosphamide therapy not only for proteinuria but also for renal function.