Vasculitis is characterized by inflammation of blood vessels. It can be primary or secondary to other diseases. Primary vasculitis syndromes include Granulomatosis with Polyangiitis (GPA, also known as Wegener's), which involves necrotizing granulomatous inflammation and vasculitis that commonly affects the lungs and kidneys. Diagnosis of GPA involves laboratory tests, biopsy of affected tissues showing vasculitis and granulomas, and testing positive for antineutrophil cytoplasmic antibodies (ANCA). Treatment is with corticosteroids and immunosuppressants to induce remission.