ABSTRACT
Granulomatosis with polyangiitis (GPA) is a systemic autoimmune disease of unknown aetiology, histologically characterized by granulomatous inflammation of the respiratory tract with necrotizing vasculitis of small and mediumsized blood vessels and focal or proliferative glomerulonephritis. It has previously been known as Wegener’s granulomatosis, but its name has changed, initially to cANCA-positive vasculitis and most recently to GPA.1 Classically, it affects the nose, lungs and kidneys, but it can affect any organ. It is also now recognized that more localized forms of the disease can occur, and up to 25 per cent of patients may only complain of sinonasal symptoms. The true incidence is therefore likely to be under-reported, but is estimated at approximately 10 per million per annum, with a prevalence of up to 100 per million in Europe. The average age at onset is 40-55 years, but it may occur at any age. Men and women are equally
affected, but it is predominantly a disease of Caucasians (93 per cent).
