A rare primary membranoproliferative glomerulonephritis characterized by complement dysregulation occurring in the fluid phase and in the glomerular microenvironment, which results in prominent complement C3 deposition in kidney biopsy samples. The disease is complement 3 glomerulopathy (MONDO_0018013). Also known as: C3 glomerulopathy, C3G, non-Ig-mediated MPGN, non-Ig-mediated membranoproliferative glomerulonephritis, non-immunoglobulin-mediated MPGN, non-immunoglobulin-mediated membranoproliferative glomerulonephritis.