Anti-LRP2 nephropathy with concurrent kidney infiltration by lymphoma.

Anti-low-density lipoprotein receptor-related lipoprotein 2 (LRP2) nephropathy/anti-brush border antibody disease is rare and characterized by tubular basement membrane, Bowman's capsule and glomerular subepithelial immune deposits on kidney biopsy. No reported cases have occurred in patients with lymphoproliferative disorders or monoclonal gammopathies. We present two cases of anti-LRP2 nephropathy that occurred in patients with progressive low-grade B-cell lymphoma and had concurrent kidney infiltration by lymphoma on biopsy. We speculate that underlying immune dysregulation related to lymphoma may contribute to the development of this rare autoimmune kidney disease in some patients.