Cranial giant cell arteritis mimickers: A masquerade to unveil.

Giant cell arteritis (GCA) is a large-vessel vasculitis that affects cranial and extra-cranial arteries. Extra-cranial GCA presents mainly with non-specific symptoms and the differential diagnosis is very broad, while the cranial form has more typical clinical picture and physicians have a lower threshold for diagnosis and treatment. Although temporal artery biopsy (TAB) has an established role, ultrasound (US) is being increasingly used as the first-line imaging modality in suspected GCA. Vasculitides (especially ANCA-associated), hematological disorders (mainly amyloidosis), neoplasms, infections, atherosclerosis and local disorders can affect the temporal arteries or might mimic the symptoms of cranial GCA and produce US and TAB findings that resemble those of temporal vasculitis. Given that prompt diagnosis is essential and proper treatment varies significantly among these diseases, in this review we aimed to collectively present disorders that can masquerade cranial GCA.