Which statement best describes Thromboangiitis obliterans (Buerger disease)?

• A. Affects large arteries with atherosclerotic plaques
• B. Hypercoagulable state due to antiphospholipid antibodies
• C. Inflammation of medium-sized arteries and veins with thrombotic occlusion causing distal ischemia and gangrene
• D. Vasculitis of small arteries with immune complex deposition

Answer: (C)

Thromboangiitis obliterans is a nonatherosclerotic inflammatory disease of small- and medium-sized vessels in the extremities, where the vessel lumen becomes occluded by an inflammatory thrombus. This process often involves both arteries and veins and can extend to surrounding nerves, leading to distal ischemia that may progress to ulcers and gangrene. It most strongly associates with tobacco use, making smoking cessation the cornerstone of management. This pattern—segmental vasculitis with thrombosis in the distal limbs—fits best, and it distinguishes the condition from diseases that affect large arteries with plaques, from hypercoagulable states caused by antiphospholipid antibodies, or from immune complex–mediated small-vessel vasculitis.