An update on the epidemiology of ANCA-associated vasculitis
ANCA-associated vasculitis (AAV) includes granulomatosis with polyangiitis, microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis. Epidemiological studies in AAV are important in understanding possible aetiologic mechanisms and facilitating healthcare planning. However, epidemiological studies present a number of challenges including clear definition of cases differentiated fr