Granulomatous polyangiitis

Wegener's granulomatosis is a vasculitis of medium and small arteries, including venules and arterioles. It produces granulomatous inflammation of the respiratory tracts and necrotizing, pauci-immune glomerulonephritis.

While it is considered a rare disease (3 cases per 100,000 people in the U.S.), Wegener's is the most common cause of saddle nose deformity in USA (nose flattened due to destruction of nasal septum by granulomatous inflammation). It also has a high mortality rate if untreated.

Diagnosis
Almost all patients with Wegener's have the c-ANCA form of antineutrophil cytoplasmic antibodies, but not vice versa.