Giant Cell Arteritis versus Takayasu Arteritis: An Update

Giant cell arteritis (GCA) and Takayasu Arteritis (TAK) are two systemic granulomatous vasculitides affecting medium- and large-sized arteries. Similarities in GCA and TAK regarding the clinical presentation, the systemic inflammatory response and the distribution of the arterial lesions, have triggered a debate over the last decade about whether GCA and TAK represent two different diseases, or are age-associated different clinical phenotypes of the same disease. On the other hand, there are differences regarding epidemiology, several clinical features (eg, polymyalgia rheumatica in GCA) and treatment. The aim of this review is to present the latest data regarding this question and to shed some light on the differences and similarities between GCA and TAK regarding epidemiology, genetics, pathogenesis, histopathology, clinical presentation, imaging and treatment. The existing data in literature support the opinion that GCA and TAK are different clinical entities.