Vasculitis is inflammation of the blood vessels and can have various symptoms, effects, and treatments, depending on the cause of the inflammation and which blood vessels, specifically, are inflamed.
Vasculitis that occurs with no apparent cause is called primary vasculitis. Vasculitis that appears because of another condition is called secondary vasculitis. Secondary vasculitis may result from an infection, an allergic reaction, or a cancer that affects the blood cells. It may also be the result of an autoimmune condition, such as rheumatoid arthritis (RA). Secondary vasculitis that arises as a result of RA is referred to as rheumatoid vasculitis.
Both arteries, which circulate blood throughout your body, and veins, which return it to your heart, can be affected by vasculitis. Vasculitis may be acute and last only a short time, or it may be chronic and persist for a while.
When the inflamed blood vessels are arteries, the condition is also referred to as arteritis. When the veins are inflamed, it may be called venulitis. The term angiitis may be used to refer to either.
It is possible to have vasculitis in the blood vessels running to or from any place in the body. Because of this, the condition can arise in any organ or body system and can lead to a wide variety of serious complications, from heart attack, to stroke, to problems in the lungs. In some cases it can be fatal.
The causes of vasculitis are varied and not always well understood. It is often an autoimmune condition, in which the body’s immune system sees the blood vessel as a foreign invader and attacks it. At other times, it can be the result of an infection such as hepatitis B. Other possible causes include medicines, exposures to chemicals, some cancers such as lymphoma or multiple myeloma, and rheumatic conditions such as rheumatoid arthritis and lupus.
There is much debate over whether good control of RA lowers the risk of developing rheumatoid vasculitis. A 2009 study appearing in the journal Arthritis and Rheumatism showed steep declines in the rate of rheumatoid vasculitis starting around the time that anti-tumor necrosis factor-alpha drugs and other so-called biologics were coming into wide use. Whether this can be linked to better treatment for RA is unknown. Once a person develops rheumatoid vasculitis, however, improved control over his RA will often help to control his vasculitis.
How many people have the condition varies widely depending on which vessels are involved and exactly how it is defined from one set of guidelines to the next. In addition, the incidence of a particular kind of vasculitis may change depending on the population group.