Diagnostic approach in giant cell arteritis

Giant cell arteritis (GCA), also known as temporal arteritis, is the most common form of vasculitis in the elderly. While initially described as involving the temporal arteries, GCA can also affect the aorta and its major branches. Despite the increased use of imaging modalities and the availability of temporal artery biopsy, diagnosing GCA remains challenging. GCA should be considered a spectrum, with diagnostic methodologies tailored to the prevalent symptoms. The sensitivity and specificity of different diagnostic approaches can vary depending on the clinical setting. Timing in diagnosing GCA is crucial to prevent serious complications, such as blindness and cerebrovascular ischemic events. While the prompt initiation of glucocorticoids (GCs) has reduced the incidence of major ischemic events, an uncertain diagnosis may expose the patient to unnecessary harm, such as complications from overtreatment or organ damage due to inadequate control of vasculitis. This narrative review will summarize the most widely available diagnostic techniques for GCA and outline our approach for cases where the diagnosis may be uncertain.