**Core Concept**
PAN (Polyarteritis Nodosa) is a medium- and small-vessel vasculitis characterized by necrotizing inflammation of the arterial walls, leading to aneurysm formation and thrombosis. This results in a wide range of clinical manifestations, including hypertension, renal failure, and gastrointestinal bleeding.

**Why the Correct Answer is Right**
PAN is known for its involvement of medium-sized arteries, which are typically spared in other forms of vasculitis such as Kawasaki disease and giant cell arteritis. The angiographic findings in PAN are often characterized by aneurysms, stenoses, and occlusions of the affected vessels, which is a result of the inflammatory process. This process leads to the destruction of the elastic lamina and the internal elastic lamina, causing the vessel to dilate and form aneurysms.

**Why Each Wrong Option is Incorrect**
**Option A:** Kawasaki disease primarily affects the coronary arteries and is characterized by inflammation of the vessel walls, but it is more commonly seen in children and typically involves the large vessels. The angiographic findings in Kawasaki disease usually show coronary artery aneurysms.
**Option C:** Takayasu arteritis is a large-vessel vasculitis that primarily affects the aorta and its major branches. Angiography in Takayasu arteritis may show stenosis or occlusion of the affected vessels, but it typically spares the medium-sized vessels.
**Option D:** Giant cell arteritis is a large-vessel vasculitis that primarily affects the temporal arteries and other branches of the external carotid artery. Angiography in giant cell arteritis may show stenosis or occlusion of the affected vessels, but it typically spares the medium-sized vessels.

**Clinical Pearl / High-Yield Fact**
In PAN, the presence of aneurysms and stenoses in multiple medium-sized arteries should raise suspicion for this diagnosis, especially in the context of systemic symptoms such as hypertension, renal failure, or gastrointestinal bleeding.

✓ Correct Answer: B. PAN