Studies on the Epidemiology and Outcome of Primary Systemic Vasculitis
Primary Systemic Vasculitides [PSV: Wegener's granulomatosis (WG), microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and polyarteritis nodosa (PAN)] are rare systemic diseases of unknown etiology; if untreated, they are associated with high morbidity and mortality rates. Changes in the classification and diagnostic improvements during the last decades have increased reported prevalence