Pathogenesis (disease development)
The cause of giant cell arteritis is unknown. Various environmental factors are thought to be triggers.
Giant cell arteritis is a systemic segmental giant cell arteritis of the large and medium-sized vessels. The inflammation originates in the adventitia (enveloping layer of connective tissue surrounding the blood and lymphatic vasculature) of the affected arteries.
Histology (fine tissue examination) reveals granulomatous inflammation of the vessel wall, usually with evidence of giant cells. This may result in vascular stenosis (vasoconstriction) or vascular obliteration (vascular occlusion).
