Vasculitis: do we know more to classify better?

The systemic vasculitides are a heterogeneous group of disorders characterized by the inflammation of blood vessels. The development and implementation of advanced diagnostic tests and genetic studies have resulted in substantial improvement in our understanding of vasculitis pathogenesis, resulting in the revision of the nomenclature and classification for vasculitis. Multicenter, collaborative studies are currently underway to develop improved diagnostic criteria. In this review, the major nomenclature and classification systems for vasculitides are summarized, with special emphasis on those emerging from the recent 2012 Chapel Hill Consensus Conference (CHCC).