The onset of the disease is gradual and marked by vague symptoms, such as upper respiratory tract symptoms, pain in the joints, weakness and fatigue.

Upper respiratory tract
Upper respiratory tract symptoms suggestive of Wegener’s include sinus pain, discolored or bloody discharge from the nose. A common sign of the disease is almost constantly runny nose and other cold-like symptoms that do not go away or become increasingly worse.

Lungs
The lungs are affected in most patients with Wegener's granulomatosis, although not all patients exhibit symptoms. Signs suggestive of lung involvement include cough, coughing up blood, and shortness of breath and chest discomfort.

Kidneys
Three-quarters of people with Wegener’s will develop kidney problems, which however usually do not cause symptoms in the early stages. If detected by blood and urine tests, a prompt treatment will prevent long-term kidney damage.

Musculoskeletal system
Two-thirds of people with Wegener’s will have muscle pain, joint pain or swelling of the joints.

Eyes
Wegener's granulomatosis can affect the eyes in several ways. Patients may develop inflammation of the inner lining of the eyelid (conjunctivitis) or scleritis (inflammation of the white part of the eyeball), as well as eye-related problems. Signs of eye inflammation include redness, burning or pain.

Skin lesions
About half of people with Wegener’s will develop skin lesions, which are usually inflamed reddish patches of skin that may or may not be painful.

Other symptoms
Rarely, some people with Wegener’s my experience narrowing of the trachea. The symptoms can include voice change, hoarseness, shortness of breath, or cough. The nervous system and heart also may be affected, although relatively rarely.

Prevalence of Wegener’s is nearly equal in men and women. The disease tends to occur in middle age, although it has been documented in much younger and much older patients. Wegener’s is a rare disorder, affecting one in 30,000 people to one in 50,000 people, according to estimates from the Wegener’s Granulomatosis Association.

The cause of Wegener’s is unknown. Some researchers have hypothesized that an infection, caused by a bacterium or a virus, may be involved, but no such infectious agent has been isolated to date.

Early diagnosis is crucial to prevent damage from occurring. There is no single test to detect Wegener’s. Doctors usually diagnose the disease by a process of elimination. If Wegener’s is suspected, the doctor may order a series of blood tests to determine if any internal organs are affected.X-rays are also helpful in detecting respiratory problems and lung involvement.The only fool-proof way to diagnose Wegener's granulomatosis is by performing a biopsy of an involved organ, such as the sinuses, the lungs or kidneys.

With prompt and appropriate treatment, most people with Wegener’s have a good prognosis. In most cases, treatment consists of a combination of steroids and cytotoxic medications, used to suppress the immune system. Although these medicines are helpful in treating Wegener's granulomatosis, patients and their doctors should be aware that they potentially have serious side effects.