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Overview of Vasculitis

Reviewed/Revised Modified Aug 2025
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What is vasculitis?

Vasculitis is inflammation of blood vessels.

  • Vasculitis can affect any size or type of blood vessel

  • It may affect many blood vessels in many organs or just a few vessels in 1 or 2 organs

  • The inflamed blood vessels become narrow or clogged and don't deliver enough blood to your organs

  • Vasculitis can be caused by certain infections, medicines, or illicit drugs

  • You may have a fever and feel tired, then get other symptoms depending on which organs are affected

  • Doctors do a biopsy (take a sample of tissue from an affected organ) to look at its blood vessels

  • Doctors have you take steroids (also sometimes known as glucocorticoids or corticosteroids) or other medicines to limit inflammation

What causes vasculitis?

Usually, doctors can't find a cause of vasculitis.

Sometimes, infections, toxins, medicines, or illicit drugs trigger the disorder.

The inflamed blood vessels often narrow down or get clogged up. These vessels can't deliver enough blood to the organ they're in. Without enough blood, those organs don't work right.

What are the symptoms of vasculitis?

Vasculitis can cause general symptoms such as fever, night sweats, muscle and joint pain, weight loss, and feeling tired.

Other specific symptoms depend on which blood vessels are affected, such as those:

  • In your skin: A rash or sores (ulcers) on your legs

  • In your brain: Headache and confusion

  • In your kidneys: Kidney failure

  • In your lungs: Trouble breathing

  • To your nerves: Numbness, tingling, and weakness in your arms or legs

  • To your eyes: Blurry vision or blindness

You may need urgent treatment for these symptoms.

How can doctors tell if I have vasculitis?

Vasculitis is uncommon. Doctors often don't suspect it when symptoms first develop. When certain combinations of symptoms last long enough, doctors may suspect vasculitis. To confirm you have vasculitis, doctors do:

  • Blood tests

  • Sometimes a biopsy (test a sample of tissue from an affected organ)

You may need other tests to check which organs are affected. For example, you may have a urine test to see if your kidneys are affected. You may have an EKG/ECG (electrocardiography) to see if your heart is affected. If your lungs seem to be affected, doctors may do a chest x-ray and CT (computed tomography) scan.

How do doctors treat vasculitis?

Doctors treat the cause of vasculitis. Sometimes that means you need to stop taking medicines that they suspect are causing the vasculitis.

Whatever the cause, doctors try to stop the blood vessel inflammation using:

  • Steroids (also sometimes known as glucocorticoids or corticosteroids)

  • Medicines to block your immune system (immunosuppressants)

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