GCA (Temporal arteritis)
Overview Giant cell arteritis (GCA) is a granulomatous vasculitis of medium and large arteries that almost exclusively affects people aged >50 years and is commonly associated with polymyalgia rheumatica (PMR).
Emergency department (ED) priorities are rapid recognition, risk stratification and prompt initiation of treatment when indicated - untreated GCA can cause sudden, irreversible visual loss and other major complications (eg, thoracic aortic aneurysm).
Do not delay corticosteroids for imaging or biopsy when clinical suspicion is high (NICE CG150; NICE TA518; gov.uk ombudsman summary).
Epidemiology and associations
- Typical age: almost always >50 years (peak in the 7th decade).
- Sex: more common in women.
- Association with PMR: 40-60% of patients with GCA have PMR symptoms; 10-20% of PMR patients develop GCA.
- Long-term risk: large-vessel involvement (eg, aortic aneurysm); surveillance is arranged by specialist teams.
Pathophysiology Granulomatous inflammation of the media and adventitia of medium and large arteries (commonly branches of the superficial temporal artery and the aorta) → luminal occlusion causing ischaemia (eg, optic nerve) or vessel-wall weakening leading to aneurysm.
Clinical presentation - what to ask for
- New persistent headache in a patient aged >50 is a red-flag presentation. Headache is often temporal but may be diffuse.
- Red-flag symptoms (threatened vision / high risk):
- New visual disturbance (blurring, transient visual obscurations, sudden loss).