Wegener's granulomatosis: An uncommon type of inflammation of small arteries and veins (vasculitis) that classically involves the vessels supplying the tissues of the lungs, nasal passages (sinuses), and kidneys.
Wegener's granulomatosis usually affects young or middle-aged adults.
The diagnosis of Wegener's granulomatosis is confirmed by finding evidence of vasculitis and abnormal cellular formations called granulomas on biopsy of tissue involved by the inflammatory process.
Wegener's granulomatosis is a serious disease. Without treatment, it can be fatal within months. Treatment is directed toward stopping the inflammation process by suppressing the immune system.