Question

Which of the following is a classic example of a MEDIUM-vessel vasculitis?

• A. Leukocytoclastic (cutaneous small-vessel) vasculitis
• B. Polyarteritis nodosa (PAN)
• C. Granulomatosis with polyangiitis (GPA)
• D. Microscopic polyangiitis (MPA)

Hint:

PAN and Kawasaki = medium vessel; GPA/MPA = small-vessel ANCA-associated.

Answer 1

The Correct Option is B

Step 1: Recall the Chapel Hill vasculitis classification by vessel size.
Vasculitides are grouped as large-vessel (Takayasu, giant cell), medium-vessel (polyarteritis nodosa, Kawasaki disease), and small-vessel (ANCA-associated and immune-complex types).

Step 2: Categorise each option.
• Leukocytoclastic vasculitis: a small-vessel (postcapillary venule) vasculitis - not medium.
• PAN: the prototypical medium-vessel vasculitis affecting muscular arteries, classically ANCA-negative and associated with hepatitis B.
• GPA: an ANCA-associated small-vessel vasculitis.
• MPA: an ANCA-associated small-vessel vasculitis.

Step 3: Choose the medium-vessel disease.
Among the options the medium-vessel vasculitis is polyarteritis nodosa (PAN).

Key fact: PAN and Kawasaki disease are the classic medium-vessel vasculitides; GPA and MPA are small-vessel (ANCA-associated).