Membranoproliferative glomerulonephritis is characterised by
expansion of the mesangium with varying degrees of mesangial
proliferation. The glomerular capillary loops become patchily
thickened and show a double contour on silver stains. Electron
microscopy reveals interposition of mesangial cell processes
between the epithelial and endothelial sides of the GBM, and
characteristic sub-endothelial electron dense deposits.