Malignant hypertension can produce onion-skin lesions in vessels via which arteriolar pathology?

• A. Hyaline Arteriolosclerosis
• B. Atherosclerosis
• C. Monckeberg Medial Sclerosis
• D. Hyperplastic Arteriolosclerosis

Answer: (D)

Onion-skin arteriolar changes come from hyperplastic arteriolosclerosis, a response to severe, malignant hypertension. The vessels undergo concentric, laminated thickening due to smooth muscle cell proliferation and reduplication of basement membranes, producing the distinctive onion-skin appearance and narrowing the lumen. This pattern is classic for malignant hypertension and differs from other arteriolar changes: hyaline arteriolosclerosis shows homogeneous pink deposition from long-standing or diabetic/benign hypertension; atherosclerosis involves large- to medium-sized arteries with lipid plaques; Monckeberg medial sclerosis is calcification of the media in muscular arteries without the same arteriolar onion-skin pattern.