Your doctor will diagnose vasculitis based on your signs and symptoms, your medical history, a physical exam, and test results.
                
Specialists Involved
                
Depending on the type of vasculitis you have and the organs affected, your doctor may refer you to various specialists, including:
                
A rheumatologist (joint and muscle specialist)
                
An infectious disease specialist
                
A dermatologist (skin specialist)
                
A pulmonologist (lung specialist)
                
A nephrologist (kidney specialist)
                
A neurologist (nervous system specialist)
                
A cardiologist (heart specialist)
                
An ophthalmologist (eye specialist)
                
A urologist (urinary tract and urogenital system specialist)
                
Diagnostic Tests and Procedures
                
Many tests are used to diagnose vasculitis.
                
Blood Tests
                
Blood tests can show whether you have abnormal levels of certain blood cells and antibodies (proteins) in your blood. These tests may look at:
                
Hemoglobin and hematocrit. A low hemoglobin or hematocrit level suggests anemia, a complication of vasculitis. Vasculitis can interfere with the body's ability to make enough red blood cells. Vasculitis also can be linked to increased destruction of red blood cells.
                
Antineutrophil cytoplasmic antibodies (ANCA). These antibodies are present in people who have certain types of vasculitis.
                
Erythrocyte sedimentation rate (ESR). A high ESR may be a sign of inflammation in the body.
                
The amount of C-reactive protein (CRP) in your blood. A high CRP level suggests inflammation.
                
Biopsy
                
A biopsy often is the best way for your doctor to make a firm diagnosis of vasculitis. During a biopsy, your doctor will take a small sample of your body tissue to study under a microscope. He or she will take the tissue sample from a blood vessel or an organ.
                
A pathologist will study the sample for signs of inflammation or tissue damage. A pathologist is a doctor who specializes in identifying diseases by studying cells and tissues under a microscope.
                
Blood Pressure
                
People who have vasculitis should have their blood pressure checked routinely. Vasculitis that damages the kidneys can cause high blood pressure.
                
Urinalysis
                
For this test, you'll provide a urine sample for analysis. This test detects abnormal levels of protein or blood cells in the urine. Abnormal levels of these substances can be a sign of vasculitis affecting the kidneys.
                
EKG (Electrocardiogram)
                
An EKG is a simple, painless test that records the heart's electrical activity. You might have this test to show whether vasculitis is affecting your heart.
                
Echocardiography
                
Echocardiography is a painless test that uses sound waves to create a moving picture of your heart. The test gives information about the size and shape of your heart and how well your heart chambers and valves are working.
                
Chest X Ray
                
A chest x ray is a painless test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. Abnormal chest x-ray results may show whether vasculitis is affecting your lungs or your large arteries (such as the aorta or the pulmonary arteries).
                
Lung Function Tests
                
Lung function tests measure how much air you can breathe in and out, how fast you can breathe air out, and how well your lungs deliver oxygen to your blood.
                
Lung function tests can help your doctor find out whether airflow into and out of your lungs is restricted or blocked.
                
Abdominal Ultrasound
                
An abdominal ultrasound uses sound waves to create a picture of the organs and structures in your abdomen. The picture may show whether vasculitis is affecting your abdominal organs.
                
Computed Tomography Scan
                
A computed tomography (to-MOG-rah-fee) scan, or CT scan, is a type of x ray that creates more detailed pictures of your internal organs than a standard x ray. The results from this test can show whether you have a type of vasculitis that affects your abdominal organs or blood vessels.
                
Magnetic Resonance Imaging
                
A magnetic resonance imaging (MRI) test uses radio waves, magnets, and a computer to create detailed pictures of your internal organs.
                
Other Advanced Imaging Techniques
                
Several new imaging techniques are now being used to help diagnose vasculitis. Duplex ultrasonography combines an image of the structure of the blood vessel with a color image of the blood flow through that vein or artery. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) identifies areas that show higher glucose metabolism leading to problems in the blood vessels.
                
Angiography
                
Angiography (an-jee-OG-ra-fee) is a test that uses dye and special x rays to show blood flowing through your blood vessels.
                
The dye is injected into your bloodstream. Special x-ray pictures are taken while the dye flows through your blood vessels. The dye helps highlight the vessels on the x-ray pictures.
                
Doctors use angiography to help find out whether blood vessels are narrowed, swollen, deformed, or blocked.