Giant Cell Arteritis
Giant cell arteritis (GCA), also referred to as temporal arteritis, is a variant of large-vessel vasculitis. GCA should be considered in the differential diagnosis in patients aged >50 years, who present with headache, abrupt onset of visual disturbances, unexplained fever, a high erythrocyte sedimentation rate, and high serum C-reactive protein levels. Diagnosis of GCA is based on accurate interpretation of laboratory data, temporal artery biopsy findings, and imaging study results. Imaging modalities used for GCA include positron emission tomography, computed tomography (CT), CT angiography, and conventional magnetic resonance angiography. Biopsy is the gold standard for diagnosis of GCA. Glucocorticoids (GCs) are used as standard treatment to induce remission and also for maintenance therapy. However, clinicians should be aware of the adverse effects of GC treatment, including hyperglycemia, an immunocompromised state, and delirium. If adverse effects outweigh the benefits of GC treatment, it is necessary to consider switching to or adding an immunosuppressant to the therapeutic regimen.