Renal biopsy is divided into three parts:
- Light microscopy
- Immunofluorescence
- Electron microscopy
For light microscopy ,renal biopsy is routinely fixed in neutral buffered formaldehyde.
Sections are stained by:
- Hematoxylin and eosin (for general architecture of kidney and cellularity)
- Periodic acid schiff: to highlight basement membrane and connective tissue matrix
- Congo red- for amyloid
For electron microscopy, tissues are fixed in glutaraldehyde.
In immunofluorescence, tissue deposits of IgG, IgA, IgM, C3, fibrin light chains can be detected by using appropriate antibodies.