73-year-old male patient suffered from essential hypertension. He died from a massive hemorrhagic stroke (see also slide A III 38; specimen from autopsy).
- A section of the kidney with cortex and medulla is shown.
- Several small foci of cortical atrophy are present. In these, globally sclerotic glomeruli and atrophic tubuli are surrounded by interstitial fibrosis and a mononuclear infiltrate.
- Arteriolar hyalinization: the wall of small arteries is thickened and the lumen is narrowed. Homogenous, amorphous material is deposited and atrophy of the muscle layer ensues. Earlier deposits are focal, not circumferential leading to splitting of the arteriolar wall.
- Some arterioles do not display hyalinosis but fibrosis of the muscularis.
- The larger vessels display intima fibrosis and fragmentation of the lamina elastica interna (arteriosclerosis).
Arteriolar hyalinization: EM studies revealed that lipids and proteins are incorporated between the endothelial cells and the underlying basal lamina. With time the hyaline lesions extend through the basal lamina and infiltrate the interstitial spaces between smooth muscle cells.