Classification of large vessel vasculitis: Can we separate giant cell arteritis from Takayasu arteritis?

The two main variants of large vessel vasculitis include Takayasu arteritis and giant cell arteritis. While these two conditions have historically been considered different conditions, recent evidence questions whether they are a spectrum of the same disease. Classification criteria are limited in distinguishing between cases with phenotypic overlap. The limitations of the current criteria and directions of future research are reviewed.