What is it?
Vasculitis is a term for a group of rare diseases that have in common inflammation of blood vessels. These vessels include arteries and veins. There are many types of vasculitis, and they may vary greatly in symptoms, severity and duration. Most types of vasculitis are rare, and the causes are generally not known. Vasculitis affects persons of both sexes and all ages. A few forms of vasculitis affect certain groups of people. For instance, Kawasaki disease occurs only in children. IgA Vasculitis (Henoch-Schönlein) is much more common in children than adults. On the other hand, giant cell arteritis occurs only in adults over 50 years old.
Vasculitis can result in poor blood flow to tissues throughout the body, such as the lungs, nerves and skin. Thus, vasculitis has a wide range of signs and symptoms (what you see and feel), such as:
- Shortness of breath and cough
- Numbness or weakness in a hand or foot
- Red spots on the skin (“purpura”), lumps (“nodules”) or sores (“ulcers”)
On the other hand, vasculitis of the kidneys may produce no symptoms at first but is still a serious problem. Vasculitis can be mild or disabling, or even lead to death. Patients can have one episode of vasculitis or have repeated episodes over several years.
Complications of Vasculitis
Complications of vasculitis depend on the type and severity of your condition. Or they may be related to side effects of the prescription medications you use to treat it. Complications of vasculitis include:
- Organ damage. Some types of vasculitis can be severe, causing damage to major organs.
- Blood clots and aneurysms. A blood clot may form in a blood vessel, obstructing blood flow. Rarely, vasculitis will cause a blood vessel to weaken and bulge, forming an aneurysm (AN-yoo-riz-um). You may need surgery to remove an aneurysm.
- Vision loss or blindness. This is a possible complication if giant cell arteritis is left untreated.
- Infections. These include serious and life-threatening conditions, such as pneumonia and blood infection (sepsis).
What causes Vasculitis?
We do not know what causes most types of vasculitis. Genetic factors (different genes) appear be somewhat important in the disease. Vasculitis is thought to be an autoimmune disease, which means the body comes under attack by its own immune system. In vasculitis, the immune system attacks blood vessels. Some cases of vasculitis are caused by reactions to medicines. Also, some chronic (long-term) infections, including with hepatitis C or hepatitis B virus, can cause vasculitis.
Physicians suspect vasculitis when a patient has symptoms and abnormal results of the physical exam, lab tests or both, and there is no other clear cause. The most common tests are:
- Biopsy—surgical removal of a small piece of tissue for inspection under a microscope
- Angiography—a type of X-ray to look for abnormalities of blood vessels
- Blood tests
For most patients, doctors can detect the type of vasculitis based on the size of the affected blood vessels (see Table) and the organs involved. To find small-vessel vasculitis, doctors most often do a biopsy, such as of the skin or a kidney. Detection of medium-vessel vasculitis happens by either biopsy (for instance, of skin, nerve or brain) or angiography. Angiography also is the test that often finds large-vessel vasculitis. Detecting giant cell arteritis often involves a biopsy of an artery in the scalp.
A few forms of vasculitis, such as Behçet’s disease and Kawasaki disease, are usually detected on the basis of a collection of clinical findings rather than biopsy or angiography.
Some blood tests are so suggestive of a certain type of vasculitis that a positive (abnormal) test can be enough evidence to help doctors make the diagnosis. The most useful of these tests is for “antineutrophil cytoplasmic antibodies”—often referred to as ANCA. A positive ANCA test can help detect these types of vasculitis: granulomatosis with polyangiitis (Wegener’s), microscopic polyangiitis or eosinophilic granulomatosis with polyangiitis (Churg-Strauss). Other lab tests can show damage to organs, but the tests are not enough to prove vasculitis.
How is it treated?
Glucocorticoids: Glucocorticoids (prednisone, prednisolone or others), often referred to as “steroids,” are an important part of treating most forms of vasculitis. The dose and length of treatment depend on how bad the disease is and how long the patient has had it. These drugs help reduce inflammation but can have long-term side effects.
Other drugs: Doctors sometimes prescribe immune-suppressing drugs because their side effects may be less serious than those of glucocorticoids. This is called “steroid-sparing” treatment. Cyclophosphamide is the strongest of these drugs, and doctors may prescribe it when severe disease endangers vital organs.
For less serious vasculitis, patients may receive methotrexate, azathioprine or other immune-suppressing drugs. Doctors often prescribe these drugs to treat other rheumatic diseases, but they are useful for vasculitis, too.
Newer drugs designed to treat other autoimmune and inflammatory diseases may also help vasculitis. Researchers found that one of these drugs, rituximab effectively treats severe cases of certain forms of vasculitis. These include granulomatosis with polyangiitis, microscopic polyangiitis and cryoglobulinemic vasculitis. Some patients with the most severe cases of these diseases may receive plasma exchange (“plasmapheresis”) or intravenous immunoglobulin (often called “IVIg”).
Surgery: Damage from severe vasculitis sometimes requires surgery. This may involve vascular bypass grafting (a surgery to redirect blood flow around a blockage in a blood vessel). Depending on where the damage is, other possible operations are sinus surgery or a kidney transplant.
Most forms of vasculitis are treatable if detected early enough, before substantial organ damage has occurred. While often effective, however, the treatments remain imperfect and require improvement. Further research is needed in all forms of vasculitis. Greater knowledge of these diseases will lead to better treatments and, some day, to cures.