Giant Cell (Temporal) Arteritis
Giant Cell Arteritis (GCA), also known as Temporal Arteritis, is a large vessel vasculitis seen in elderly women in association with polymyalgia rheumatica (PMR).
As a large vessel vasculitis, GCA often affects branches of the carotid artery, characteristically involving the temporal artery. Temporal arterial involvement presents as unilateral headache with tenderness . Involvement of the maxillary artery can lead to jaw claudication (pain with chewing). Opthalmic artery involvement can lead to permanent blindness, so patients suspected to have GCA should be immediately treated with high-dose corticosteroids, even before diagnostic confirmation.
Diagnosis is based on arterial biopsy, which reveals focal granulomatous inflammation with giant cells. Since the inflammation is focal, short biopsies may miss the inflammation and consequently miss the diganosis; therefore, longer biopsies are needed.
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