Giant cell arteritis and polymyalgia rheumatica: an update.

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are two closely related diseases in people aged 50 years and older, which are more frequently observed in Western countries. Despite being common entities, concern still exists about the epidemiology, pathogenesis, and diagnosis of both entities. New imaging techniques, such as 18 fluorodeoxyglucose-positron emission tomography, have proved to be useful in detecting large-vessel involvement in GCA. Corticosteroids are the cornerstone of the therapy in GCA and PMR. Relapses are frequent in these conditions. Unlike methotrexate and tumor necrosis factor-α antagonists, anti-interleukin-6 receptor therapy appears to be useful in patients with GCA and PMR who are refractory to corticosteroids. This review summarizes recent studies on GCA and PMR.