30-year-old female. Nephrotic syndrome. Findings in urine: proteinuria of 5.4g/24hrs, erythrocytes 4-5/HPF, leucocytes 8-10/HPF (HPF=high power field)
- In the florid stage there is massive endothelial swelling with subendothelial deposits, which appear violet-red to red in the SFOG stain.
- Diffuse, but also partly focal proliferation of mesangial cells.
- New subendothelial formation of basal membrane leading to double contour
- In some parts the structure seems distinctly lobular.
- In their further course these deposits increase in size and the glomerular sclerosis progresses further until eventually they become acellular and lose their function. The belonging tubuli become atrophic and interstitial fibrosis occurs.
Pathogenesis: The membranoproliferative form of glomerulonephritis has a different aetiology. The final common pathway are dense subendothelial deposits on electron microscopy with mesangial interposition of mesangial cells in the subendothelial spaces. A new basal membrane forms, leading to a double contour.