| Feature | Hyaline Arteriolosclerosis | Hyperplastic Arteriolosclerosis | Fibrinoid Necrosis |
|---|
| Main Cause | Chronic HT, Diabetes, Aging | Malignant HT | Malignant HT, Vasculitis (immune) |
| Key Histology | Homogeneous, pink, glassy thickening, narrow lumen | ”Onion-skin” layers, smooth muscle proliferation, very narrow lumen | Eosinophilic fibrin, inflammation, “smudged” wall |
| Severity/Context | Chronic damage (e.g., benign nephrosclerosis, lacunar infarcts) | Acute, severe, rapid damage (malignant nephrosclerosis, hypertensive emergency) | Acute, severe damage (e.g., malignant nephrosclerosis, active vasculitis) |
| Vessel Type | Arterioles, small arteries | Arterioles, small arteries | Arterioles, capillaries, venules |
