Electron micrograph in focal segmental glomerulosclerosis

Electron micrograph in focal segmental glomerulosclerosis shows diffuse epithelial cell foot process fusion with occasional loss of the epithelial cells (arrows). The other major finding is massive subendothelial hyaline deposits (asterisk) under the glomerular basement membrane (Δ). These deposits reflect insudation of plasma proteins, not the deposition of immunoglobulins. These deposits contribute to narrowing of the capillary lumens.

Electron micrograph of a normal glomerular capillary loop showing the fenestrated endothelial cell (Endo), the glomerular basement membrane (GBM), and the epithelial cells with its interdigitating foot processes (arrow). The GBM is thin, and no electron-dense deposits are present. Two normal platelets are seen in the capillary lumen.