What is rheumatoid vasculitis?
Vasculitis is a serious complication of rheumatoid arthritis. While rheumatoid arthritis affects the body's joints, vasculitis is a condition in which blood vessels become inflamed. When blood vessels become inflamed, they may become weakened and increase in size, or become narrowed, sometimes to the point of stopping blood flow. The blood vessels most often involved are arteries that bring blood to the skin, nerves, and internal organs. Veins can also be involved.
Which patients with rheumatoid arthritis get vasculitis?
Rheumatoid vasculitis most often occurs in people with at least 10 years of severe disease. In general, people who get vasculitis have many joints with pain and swelling, rheumatoid nodules, high concentrations of rheumatoid factor in their blood, and sometimes smoke cigarettes. They may also have an enlarged spleen and chronic low white cell count, a condition known as Felty's Syndrome.
Fewer than five percent of people with rheumatoid arthritis get skin vasculitis. Fortunately, far fewer people get vasculitis of larger arteries.
There is evidence to support that since the introduction of effective treatments for rheumatoid arthritis, the occurrence of rheumatoid vasculitis is far less common.
What causes rheumatoid vasculitis?
The cause of rheumatoid vasculitis is not known. An abnormally active immune system (the body's defense system) appears to play an important role in blood vessel inflammation. Evidence linking the immune system to vasculitis includes:
- High levels of rheumatoid factor
- The presence of other proteins in the blood (called immune complexes)
- Lower levels of proteins in the blood (called complement), which are used up when inflammation occurs.
- The appearance of inflamed blood vessels under the microscope, which shows immune cells within the wall of the vessel.
What are the symptoms of rheumatoid vasculitis?
When vasculitis involves the small arteries and veins that nourish the skin of the fingertips and skin around the nails, small pits in the fingertips or small sores causing pain and redness around the nails can occur. Involvement of somewhat larger arteries and veins of the skin can cause a painful red rash that often involves the legs. If the skin is very inflamed, ulcers can occur and infection becomes a complicating risk.
Vasculitis that injures the nerves can cause loss of sensation, numbness and tingling, or potentially weakness or loss of function of the hands and/or feet. The rare vasculitis of larger arteries can cause complete absence of blood flow to tissue sites supplied by the affected vessel (termed occlusion, resulting in infarction), which can cause gangrene of fingers or toes, stomach pain, cough, chest pain, heart attack, and/or a stroke if the brain is involved. This form of systemic vasculitis can also be accompanied by general symptoms such as fever, loss of appetite, weight loss, and loss of energy.