Term
| What are the 3 different types of necrosis that are generally seen and what are their distinguishing features? |
|
Definition
1) Coagulative= Protein Denaturation in Hypoxia/Ischemia
- Preserved morphology, but intracellular acidosis denatures proteolytic enzymes and block proteolysis
2) Liquefactive= Bacterial/Fungal
- Inflammatory cells and Pus
3) Caseous= Mycobacterial or TB
- Amorphous granular debris |
|
|
Term
| What cells are seen in acute inflammation vs. chronic inflammation? |
|
Definition
1) Acutely you see PMNs (minutes to days)
2) Chronically you see mononuclear lymphocytes, plasma cells, macrophages and eosinophils (if IgE-mediated or parasitic) |
|
|
Term
| Why might you see Eosinophils? |
|
Definition
| IgE-mediated inflammation Type 1 hypersensitivity (allergy) or Parasitic infection |
|
|
Term
| What are 3 histological hallmarks of necrosis? |
|
Definition
1) Increased binding of eosin to denatured proteins (eosinophilia)
2) Glassy, homogeneous, vacuolated (moth-eaten – digestion by lysosomal enzymes)
3) Dystrophic calcification (low pH, high
cytosolic Ca2+) |
|
|
Term
| When you obtain a renal biopsy containing at least 10-12 glomeruli, how is it divided up? |
|
Definition
1) Largest part fixed for 2 hours , washed, processed and cut 3-4 microns thick
2) Small portion frozen in OCT and cut 5 microns for IF
3) Smallest 1mm potion fixed in 2% glutaraldehyde for EM. |
|
|
Term
| What are the typical stains used for a renal biopsy under light microscopy? |
|
Definition
1) H & E basic morphology
2) Silver (black) for BM
3) PAS (fuscia red) for BM, deposits and glycogen
4) Trichrome (blue or green in a red background) for fibrosis and collagen III
5) Congo-red for amyloidosis |
|
|
Term
| How is a general systematic light microscopic examination of a renal biopsy carried out? |
|
Definition
1) Assess glomeruli
- Look at cell number and look for ECM changes that might indicate sclerosis, fibrosis or amyloidosis
- Look for BM thickness
2) Assess the tubules
- Necrotic (acute tubular sclerosis)
- Degenerative (atherosclerosis)
- Dilated (compensatory)
3) Assess interstitium
- Edema or inflammation in pyelonephritis or fibrosis
4) Assess the blood vessels |
|
|
Term
| How is a general systematic IF examination of a renal biopsy carried out? |
|
Definition
Results can be "linear" (anti-glomerular BM Ab) or "granular" (Systemic Lupus)
1) IgG, IgM, IgA, Kappa and Lambda light chains)
2) Complements (C1q, C3, C4)
3) Fibrinogen, Transferrin and Alpha-2-Macroglobulin |
|
|
Term
| How is a general systematic EM examination of a renal biopsy carried out? |
|
Definition
| Look at BM, foot processes and area s of electron-doense deposits |
|
|
Term
| What does it mean for a renal disease process to be focal and global? |
|
Definition
Few of the glomeruli are affected, but of those that are, ALL cells are affected.
This is different from focal, segmental, where few glomeruli are diseased and only portions of those glomeruli are affected.
This is also different from Diffuse, segmental, disease, which means there are many glomeruli affected, but only portions of each glomeruli are diseased. |
|
|
Term
| What does "Sclerosis" and "Hyalinosis" mean in terms of a renal biopsy? |
|
Definition
1) Sclerosis= Fibrosis
2) Hyalinosis= Degeneration
**Necrosis= Cell death |
|
|
