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Harvard Medical School

Wegener's Granulomatosis

What Is It?

Wegener's granulomatosis is a rare, potentially life-threatening form of inflammation of the blood vessels, called vasculitis.

The inflammation of Wegener's granulomatosis damages the walls of small- and medium-sized arteries and veins. This damage interferes with normal blood supply to nearby tissues, causing tissue in many parts of the body to be injured and destroyed. Tissues affected by Wegener's granulomatosis show islands of inflamed cells, called granulomas, when examined under the microscope.

Three areas in the body are affected most commonly the upper airways (including the sinuses, trachea and nose), lungs and kidneys. In the upper airways, tissue destruction related to Wegener's granulomatosis causes chronic (long-lasting) nasal and sinus problems. Ninety percent to 95 percent of people with Wegener's see their doctors at first because of sinusitis, persistent runny nose or frequent bloody nose. In 80 percent of people with Wegener's, inflammation targets the lungs as well, causing a respiratory illness that includes coughing, shortness of breath, wheezing or coughing up blood. Kidney damage affects 80 percent of those with Wegener's, but in many cases, this damage is mild and does not cause any symptoms. In about 20 percent of people with kidney damage from Wegener's, however, the damage is severe enough to cause symptoms of kidney failure caused by an inflammation of the kidneys. Less predictably, Wegener's granulomatosis involves other organs, including the eyes, ears, skin, joints, heart and nerves.

Although the exact cause of the inflamed blood vessels of Wegener's granulomatosis is unknown, research suggests an autoimmune disorder, an illness in which the body's immune defenses mistakenly attack the body's own cells and tissues. In Wegener's granulomatosis, this misdirected immune attack is aimed at the blood vessels, triggering inflammation and damage. So far, researchers have found at least one immune protein that attacks the body that appears to be related to the damage of Wegener's. This immune protein called antineutrophil cytoplasmic antibody (ANCA) has been identified in the blood of many people with active Wegener's granulomatosis.

Wegener's granulomatosis is rare, affecting only 11 in every 1 million people each year in the United States. Although it has been reported in people of all races and age groups, it typically affects middle-aged Caucasians, usually beginning at about age 40 to 50. It is slightly more common in men.