Membranous nephropathy (MN) is the most common cause of adult-onset nephrotic syndrome. MN is characterized by immune complex deposition in the subepithelial space of the glomeruli. Neural epidermal growth factor-like 1 protein (NELL1) is one of the newly identified antigens in MN. Glomerulonephritis associated with monoclonal immunoglobulin deposits is pathologically characterized by the presence of a single heavy-chain subclass and a single light-chain isotype deposition, most commonly IgG3κ. In glomerulonephritis with monoclonal IgG deposition disease, membranous pattern of IgG deposits is rare. Here we report an exceptional case of NELL1-positive MN with monoclonal IgG3λ deposition who exhibited a favorable response to glucocorticoid monotherapy.
憲史 et al. (Sun,) studied this question.