Advanced (malignant) Renal Hypertension with arteriolar nephrosclerosis
Most people with mild hypertension (benign) have some degree of arteriolar sclerosis (hardening and thickening) of the small arterioles and glomerular capillaries in the cortex of the kidney. When hypertension is severe (malignant) the sclerosis worsens causing destruction of the small vessels, ischemia and fibrosis of the cortex, and rapid progression to renal failure.
A granular surface of the kidney may be present in both benign and malignant hypertension and is indicative of atrophy and fibrosis of the cortex due to the destruction of the small blood vessels. The degree of the granulation depends on the duration of the hypertension.