Arthritis and Takayasu's Arteritis
What Causes Takayasu's Arteritis?
The exact cause of Takayasu's arteritis is unknown.
Who Gets Takayasu's Arteritis?
Takayasu's arteritis most often affects young Asian women, but it also can affect children and adults of all ages and ethnic backgrounds. At diagnosis, Takayasu's arteritis patients often are between the ages of 15 and 35.
Every year in the U.S., two to three people are diagnosed with Takayasu's arteritis for every one million Americans.
How Is Takayasu's Arteritis Diagnosed?
The diagnosis of Takayasu's arteritis is based on a combination of factors, including:
- A complete medical history and careful physical exam to exclude other illnesses that may have similar symptoms
- Imaging studies (such as MRI, X-rays, and angiograms), which show location and severity of vessel damage
- Presence of a bruit. Significant narrowing of blood vessels may result in turbulent blood flow through the narrowed area that creates an unusual sound called a "bruit."
Note: With most other forms of vasculitis, a biopsy (tissue sample) of the affected area confirms the presence of blood vessel inflammation. A biopsy is most appropriate when easily accessible areas, such as the skin, are affected. However, when large blood vessels are affected, a biopsy is often not practical because of the risks associated with surgery.
How Is Takayasu's Arteritis Treated?
Corticosteroids -- often called simply "steroids" -- are the most common treatment for Takayasu's arteritis. Steroids work within hours after the first dose is given. While this drug often is dramatically effective, it may be only partially effective for some people.
Once it is apparent that the disease is under control, doctors slowly reduce the dosage of prednisone (a steroid) to sustain improvement, thereby trying to minimize treatment side effects. In some people, it is possible to gradually discontinue medication without a relapse.
As the dosage of prednisone is gradually reduced, about half of all patients will have recurrent symptoms or progression of illness. This has led researchers to explore additional treatments to produce remission. Among medications that have been tried, with varying degrees of success, are immunosuppressive drugs such as methotrexate.
When these drugs are added to prednisone to treat Takayasu's arteritis, 50% of patients who had previously relapsed will achieve remission and be able to gradually discontinue prednisone. Overall, about 25% of patients will have disease that is not entirely controlled without continued use of these treatments. This emphasizes the need for continuing research to identify better and less toxic treatments for Takayasu's arteritis and other forms of vasculitis.
Many patients with Takayasu's arteritis have high blood pressure. Careful control of blood pressure is very important. Inadequate treatment of high blood pressure may result in stroke, heart disease, or kidney failure. In some cases, it is desirable to stretch narrow vessel openings with a balloon (a technique known as "angioplasty") or to do a bypass operation to restore normal flow to the kidney. This may result in normal blood pressure without the need to use blood pressure drugs.
Some patients may have serious disabilities because of narrowed blood vessels that supply other sites, such as the arms or legs. Bypass operations may correct these abnormalities. Aneurysms also can be surgically repaired.