Vasculitis is a group of disorders characterized by the inflammation of blood vessels, leading to an alteration of the vascular wall. The classification of vasculitides has evolved considerably over the last few decades.

In 1990, the American College of Rheumatology established a classification of the main systemic vasculitides based on clinical, biological and histological criteria. In 1994, the Chapel Hill nomenclature has been established as the reference classification system of vasculitides and vasculitides were classified according to the size of the affected vessels. The Chapel Hill nomenclature was revised in 2012, thus enabling to integrate new vasculitides and diagnostic tools.

It is proposed here to conduct a non-interventional cohort study of the different forms of vasculitis, as defined in the Chapel Hill nomenclature. By collecting data from a large number of patients followed prospectively, our objective is to describe the clinical patterns of these diseases, the presentation, management, comorbidities and outcomes, and to evaluate their possible association with some immunological, genetic and molecular parameters.