A 28-year-old woman develops claudication of the upper extremities, absent upper limb pulses, and a 'pulseless disease' syndrome. Aortogram shows long smooth stenosis of the aortic arch and subclavian arteries. Biopsy of the involved vessel shows panarteritis with granulomatous inflammation in the media, giant cells, and intimal proliferation. ESR is elevated. What is the diagnosis, and what vessel-size classification does it belong to?

• A Takayasu arteritis — a large-vessel granulomatous vasculitis predominantly affecting the aorta and its main branches, predominantly in young Asian women ✓
• B Giant cell arteritis (temporal arteritis) — large-vessel vasculitis, but typically affects elderly patients (>50 years) and temporal/ophthalmic arteries
• C Polyarteritis nodosa — medium-vessel necrotising vasculitis involving renal and mesenteric arteries, associated with hepatitis B
• D Granulomatosis with polyangiitis (Wegener's) — small-vessel vasculitis with PR3-ANCA, involving upper and lower respiratory tracts and kidneys

Explanation

Takayasu arteritis (TA) is the prototypic large-vessel granulomatous vasculitis, characterised by panarteritis involving the aorta, its major branches (subclavian, carotid, renal, coronary), and pulmonary arteries. It predominantly affects young women of Asian descent (20–40 years). Histology shows transmural inflammation with granuloma formation, Langhans giant cells in the media/adventitia, and progressive intimal fibrosis causing luminal stenosis ('pulseless disease'). Giant cell arteritis (GCA) is a histologically identical large-vessel vasculitis but occurs in patients >50 years and predominantly affects the temporal and ophthalmic arteries; GCA also involves the aorta in a significant subset. The ACR/EULAR 2022 classification criteria differentiate them primarily by age of onset. PAN is medium-vessel and lacks granulomas; GPA involves small vessels with ANCA.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

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Written and medically reviewed by the StethoPrep medical team.