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Vasculitis occurs when your immune system injures your blood vessels by mistake. What causes this to happen is not fully known, but when it occurs, your blood vessels become inflamed and can narrow or close off. Rarely, the blood vessel wall may weaken, causing it to expand or bulge. This bulge is known as an aneurysm.
Do you want to know more about what causes vasculitis?
inflammation is part of your body’s immune response against chemicals, bacteria, viruses, and other harmful substances. When organs are in danger, your body sends special cells to protect them. These immune cells release chemicals that recruit other cells to isolate and destroy the harmful substance. This also causes the pain, heat, swelling, and redness of inflammation. The inflammation normally goes away after the harmful substance goes away. In vasculitis, the inflammation continues.