"Onion-skin" renal arteriole
Hyperplastic arteriolosclerosis is a type of arteriolosclerosis involving a narrowed lumen.
The term "onion-skin" is sometimes used to describe this form of vessel  with thickened concentric smooth muscle cell layer and thickened, duplicated basement membrane. In malignant hypertension these hyperplastic changes are often accompanied by fibrinoid necrosis of the arterial intima and media. These changes are most prominent in the kidney and can lead to ischemia and acute renal failure.
It can be caused by malignant hypertension.