What Is Arteritis?
Arteritis is a general term that refers to the inflammation of arteries -- blood vessels that carry blood away from the heart and to the rest of the body. A closely related condition called vasculitis is inflammation of blood vessels in general -- including veins and arteries.
What Is Takayasu's Arteritis?
Takayasu's arteritis is an uncommon condition in which inflammation damages large and medium-sized arteries. The arteries most commonly affected are the branches of the aorta (the main blood vessel that leaves the heart), including the blood vessels that supply blood to the arms and travel through the neck to provide blood to the brain. The aorta itself is also often affected.
Inflammation of large blood vessels may cause segments of the vessels to weaken and stretch, resulting in an aneurysm (bulging blood vessel). Vessels also can become narrowed or even completely blocked (called an occlusion).
Takayasu's arteritis was named for Dr. Mikoto Takayasu, the doctor who first described the disorder in 1908.
What Are the Symptoms of Takayasu's Arteritis?
Approximately half of all people with Takayasu's arteritis will have a sense of generalized illness. This may include low grade fevers, swollen glands, anemia, dizziness, night sweats, muscle aches, and/or arthritis.
The changes that occur in Takayasu's arteritis are often gradual, allowing alternate (collateral) routes of blood flow to develop. These alternate routes are typically smaller blood vessels. The collateral vessels may not be able to carry as much blood as the normal vessels.
In general, however, the blood flow that occurs beyond an area of narrowing is almost always adequate to allow tissues to survive. In rare cases, if collateral blood vessels are not available in sufficient quantity, the tissue that is normally supplied with blood and oxygen by those vessels will die.
Narrowing of blood vessels to the arms or legs may cause fatigue, pain, or aching due to reduced blood supply -- especially during activities such as shampooing the hair, exercising, or walking. It is much less common for decreased blood flow to cause a stroke or a heart attack. In some people, decreased blood flow to the intestines may lead to abdominal pain, especially after meals.
What Are the Symptoms of Takayasu's Arteritis? continued...
Some people with Takayasu's arteritis may not have any symptoms. Their diagnosis may be discovered when their doctor attempts to take their blood pressure and has trouble getting a reading in one or both arms. Similarly, a doctor may notice that the strength of pulses in the wrists, neck, or groin may not be equal, or the pulse on one side may be absent.
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.
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.
How Is Takayasu's Arteritis Treated? continued...
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.
How Is Takayasu's Arteritis Treated? continued...
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.
What Is the Outlook For People With Takayasu's Arteritis?
In the U.S. and Japan, Takayasu's arteritis is fatal in only about 3% of patients who have had the disease for an average of five years. This encouraging statistic is the product of recognizing the disease and treating it appropriately. Reports from other parts of the world have been less optimistic, possibly because it is not as readily recognized and treated.
Approximately 25% of patients with Takayasu's arteritis seen at The Cleveland Clinic have an entirely normal lifestyle. Another 25% have had to make some adjustments in their activities. About half have had to modify their jobs and a small number of that group became occupationally disabled.
Takayasu's arteritis is clearly a treatable disease and most patients improve. However, it is apparent that many patients have to deal with consequences of this illness that may be partially or, less often, completely disabling. Close follow-up is required as drugs used to treat the disease have side effects that should be regularly monitored by a doctor.