What are lesions of Wegner's?

1. Upper respiratory tract lesions: They range from inflammatory sinusitis to ulcerative lesions in the nose, palate, or pharynx. 2. Lower respiratory tract: Lung shows multiple, bilateral, nodular cavitary infiltrates. Microscopically, it is characterized by: a. Necrotizing granulomas: It consists of geographic patterns of central necrosis surrounded by a zone of fibroblastic proliferation with giant cells, reminiscent of mycobacterial or fungal infections. The granulomas may be either intravascular or extravascular. b. Necrotizing vasculitis of small arteries and veins. 3. Renal lesions: a. Early lesions: Glomeruli show focal and segmental necrotizing glomerulonephritis. b. Advanced lesions: They are characterized by rapidly progressive crescentic glomerulonephritis (RPGN).