Vasculitis (vas-kyu-LI-tis) is a condition that involves inflammation in the blood vessels. The condition occurs if your immune system attacks your blood vessels by mistake. This may happen as the result of an infection, a medicine, or another disease or condition.
Vasculitis is an inflammation of your blood vessels. It causes changes in the walls of blood vessels, including thickening, weakening, narrowing and scarring. These changes restrict blood flow, resulting in organ and tissue damage.