Vasculitis can be triggered by certain infections or drugs or can occur for unknown reasons.
People may have general symptoms, such as fever or fatigue, followed by other symptoms depending on which organs are affected.
To confirm the diagnosis, a biopsy is done on a sample of tissue from an affected organ to detect inflammation in the blood vessels.
Corticosteroids and other drugs that suppress the immune system are often used to reduce inflammation and relieve symptoms.
Vasculitis can affect people of all ages, but some types are more common among certain age groups.
Vasculitis may affect arteries (large, medium, or small), capillaries, veins, or a combination. It may affect a whole blood vessel or only part of it. It may affect blood vessels that supply one part of the body, such as the head, nerves, or skin; or blood vessels that supply many different organs (called systemic vasculitis). Any organ system can be affected. Sometimes vasculitis affects the skin but not the internal organs (cutaneous vasculitis).
Causes of Vasculitis
Usually, what triggers vasculitis is unknown. In these cases, the vasculitis is known as primary vasculitis. However, when infections, toxins, certain viruses (especially hepatitis viruses), and drugs trigger the disorder, it is known as secondary vasculitis.
Vasculitis may result from cancer or another disorder that causes inflammation. Presumably, the inflammation occurs when the immune system Overview of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more mistakenly identifies blood vessels or parts of a blood vessel as foreign and attacks them. Cells of the immune system, which cause inflammation, surround and infiltrate the affected blood vessels, damaging them. The damaged blood vessels may become leaky, narrow, or clogged. As a result, blood flow to the tissues supplied by the damaged vessels is disrupted. The tissues deprived of blood (ischemic areas) can be permanently damaged or die.
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Symptoms of Vasculitis
Symptoms of vasculitis may result from direct damage to the blood vessels or from indirect damage to tissues (such as nerves or organs) whose blood supply has been disrupted or reduced (ischemia).
Symptoms vary depending on the size and location of the affected blood vessels and the degree of damage caused to the affected organs. For example, the following may occur:
Skin: A rash of bluish purple spots (hemorrhages) or blotches (purpura), hives, small bumps (nodules), tiny spots (petechiae), mottled discoloration caused by dilated surface blood vessels (livedo reticularis), or sores (ulcers) on the lower legs
Peripheral nerves: Numbness, tingling, or weakness in the affected limb
Brain: Confusion, seizures, and strokes
Digestive tract: Abdominal pain, diarrhea, nausea, vomiting, and blood in the stool
Heart: Angina and heart attacks
Kidneys: High blood pressure, retention of fluid (edema), and kidney dysfunction
Joints: Joint pain or swelling
Inflammation can also cause general symptoms such as fever, night sweats, fatigue, muscle aches, loss of appetite, and weight loss.
Vasculitis can cause serious complications that require immediate treatment. For example, damaged blood vessels in the lungs, brain, or other organs may bleed (hemorrhage). Effects on the kidneys may progress rapidly, leading to kidney failure Overview of Kidney Failure This chapter includes a new section on COVID-19 and acute kidney injury (AKI). Kidney failure is the inability of the kidneys to adequately filter metabolic waste products from the blood. Kidney... read more . Eye problems may result in blindness.
Diagnosis of Vasculitis
A doctor's evaluation
Blood and urine tests
Tissue biopsy (for confirmation of diagnosis)
Sometimes imaging tests
Vasculitis is often not suspected when symptoms first develop because it is uncommon, and most of its symptoms are caused much more often by other disorders. Nonetheless, certain combinations of symptoms or the persistence of symptoms eventually leads doctors to suspect vasculitis.
The following blood and urine tests are usually done:
Complete blood count Complete blood count Doctors select tests to help diagnose blood disorders based on the person's symptoms and the results of the physical examination. Sometimes a blood disorder causes no symptoms but is discovered... read more : Abnormalities, such as lower counts of red blood cells (anemia), too many platelets, too many white blood cells, or a high proportion of certain kinds of white blood cells, can occur in vasculitis but also in many other disorders. Vasculitis may cause anemia Overview of Anemia Anemia is a condition in which the number of red blood cells is low. Red blood cells contain hemoglobin, a protein that enables them to carry oxygen from the lungs and deliver it to all parts... read more by decreasing the body’s production of red blood cells or by causing internal bleeding.
Comprehensive metabolic panel: This blood test measures substances that, when abnormal, can indicate significant damage to the kidneys or liver. The kidneys and liver are organs that are affected in various disorders that cause vasculitis.
Antibody tests: Depending on what disorder is suspected, blood is analyzed for certain antibodies Antibodies One of the body's lines of defense (immune system) involves white blood cells (leukocytes) that travel through the bloodstream and into tissues, searching for and attacking microorganisms and... read more (such as antineutrophil cytoplasmic antibodies) and complement proteins. For example, antineutrophil cytoplasmic antibodies are usually present in people who have granulomatosis with polyangiitis or microscopic polyangiitis.
Infection tests: Blood tests may be done to check for infections (such as hepatitis B Hepatitis B, Acute Acute hepatitis B is inflammation of the liver that is caused by the hepatitis B virus and that lasts from a few weeks up to 6 months. Hepatitis B is spread through contact with blood or other... read more and hepatitis C Hepatitis C, Acute Acute hepatitis C is inflammation of the liver that is caused by the hepatitis C virus and that lasts from a few weeks up to 6 months. Hepatitis C is spread through contact with blood or other... read more ) that may have triggered the vasculitis.
Inflammation tests: Blood tests are done to estimate the degree of inflammation, which vasculitis usually causes. For example, how quickly red blood cells (erythrocytes) drop to the bottom of a test tube (erythrocyte sedimentation rate, or ESR) is measured. A fast rate suggests inflammation. High levels of C-reactive protein (which the liver produces in response to bodywide inflammation) also suggest inflammation. However, inflammation has many causes other than vasculitis.
Urine test: A sample of urine is tested for red blood cells and protein. The results of this test can help doctors determine whether the kidneys are affected. This information is important because kidney inflammation can cause severe damage before symptoms develop.
Blood and urine test results may help in making the diagnosis but are usually not conclusive. For confirmation, a sample of tissue from an affected organ is usually removed and examined under a microscope (biopsy) for signs of vasculitis. An anesthetic is used to numb the area (local anesthetic), and biopsy can often be done on an outpatient basis.
Occasionally, an imaging test of the blood vessels (such as arteriography Arteriography In angiography, x-rays are used to produce detailed images of blood vessels. It is sometimes called conventional angiography to distinguish it from computed tomography (CT) angiography and magnetic... read more or computed tomography Computed Tomography (CT) In computed tomography (CT), which used to be called computed axial tomography (CAT), an x-ray source and x-ray detector rotate around a person. In modern scanners, the x-ray detector usually... read more [CT] or magnetic resonance angiography Magnetic resonance angiography (MRA) In magnetic resonance imaging (MRI), a strong magnetic field and very high frequency radio waves are used to produce highly detailed images. MRI does not use x-rays and is usually very safe... read more ) can be done instead of a blood vessel biopsy. Other imaging tests may be needed. For example, if the lungs seem to be affected, a chest x-ray is done, and doctors may also do a CT scan.
Some tests may be done to rule out other disorders that can cause similar symptoms.
Prognosis of Vasculitis
The prognosis depends on the type and severity of vasculitis and the organs that are affected. If the kidneys or heart is affected, the prognosis tends to be worse.
Treatment of Vasculitis
Treating obvious cause of vasculitis (including stopping certain drugs)
Corticosteroids and other immunosuppressants
If a cause is evident, it is treated. For example, if the vasculitis is caused by an infection, treating the infection treats the vasculitis. Drugs that are causing the vasculitis are stopped. Other treatment depends on the type and severity of the vasculitis and the organs that are affected. Typically, such treatment aims to stop the immune system Overview of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more from continuing to damage blood vessels.
If vital organs, such as the lungs, heart, brain, or kidneys, are affected, immediate treatment in a hospital is often necessary. Sometimes a team of specialists (experts in such fields as inflammation, lung disorders, or kidney disorders) is needed to provide care. Typical treatments include high doses of corticosteroids, other drugs that suppress the immune system (immunosuppressants, such as cyclophosphamide), and rituximab.
Mild types of vasculitis, such as those that affect only the skin, may require little treatment, possibly only close monitoring or treatment of the symptoms.
For most types of vasculitis, a corticosteroid (usually prednisone) is typically used first to reduce inflammation. Sometimes the corticosteroid is used with another immunosuppressant, such as azathioprine, cyclophosphamide, methotrexate, or rituximab. Drugs used to treat vasculitis can have side effects. Thus, as the inflammation is being controlled, the dose of the drugs may be slowly reduced, the corticosteroid may be stopped, and less potent immunosuppressants are used. The lowest dose that can control symptoms is used.
Once inflammation is controlled (called remission), all drugs may be stopped. Some people remain in remission indefinitely. In other people, symptoms return one or more times (called a relapse). If relapses occur often, people may need to take an immunosuppressant indefinitely. Some people have to take corticosteroids for a long time.
Side effects, such as decreased bone density (osteoporosis Osteoporosis read more ), an increased risk of infections, cataracts, high blood pressure, weight gain, and diabetes, are more likely to occur when corticosteroids are taken for a long time. To help prevent decreased bone density, people are advised to take calcium and vitamin D supplements and are often given a bisphosphonate, such as alendronate, risedronate, or ibandronate, which helps increase bone density. Bone density is measured periodically.
Immunosuppressants weaken the immune system, so the risk of developing serious infections is increased. Cyclophosphamide, a potent immunosuppressant, can cause bladder irritation, bloody urine, and, sometimes with long-term use, even bladder cancer. If cyclophosphamide is given by vein (intravenously), the drug mesna, which chemically counteracts some toxic effects of cyclophosphamide on the bladder, is also given. A complete blood count is done frequently, sometimes as often as once a week, for people who take potent immunosuppressants. Immunosuppressants may cause the number of blood cells to decrease.
All patients treated with these immunosuppressants should be monitored for opportunistic and other infections. Testing for prior infection with tuberculosis (TB) and hepatitis B should be considered because both can be reactivated by immunosuppressants. Routine vaccinations Overview of Immunization Immunization enables the body to better defend itself against diseases caused by certain bacteria or viruses. Immunity (the ability of the body to defend itself against diseases caused by certain... read more (for example, for influenza Influenza Vaccine The influenza virus vaccine helps protect against influenza. Two types of influenza virus, type A and type B, regularly cause seasonal epidemics of influenza in the United States. There are... read more and pneumonia Pneumococcal Vaccine Pneumococcal vaccines help protect against bacterial infections caused by Streptococcus pneumoniae (pneumococci). Pneumococcal infections include ear infections, sinusitis, pneumonia, bloodstream... read more ) are recommended and extremely important for people who take immunosuppressants.
People should learn as much as they can about their disorder so that they can report any major symptoms to their doctor promptly. Learning about the side effects of the drugs being used is also important. People, even when in remission, should keep in touch with their doctor because how long remission will last cannot be predicted.
More Information about Vasculitis
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
Vasculitis Foundation: Provides information for patients about vasculitis, including how to find a doctor, learn about research studies, and join patient advocacy groups