Vasculitis is the inflammation and damage to blood vessels.

Vasculitis can affect any type and size of blood vessel in the body including arteries, arterioles, veins, venules, and capillaries.

Vasculitis leads to damage to the lining of vessels, with narrowing or blockage, so that the blood flow is restricted or stopped. As a result, the tissues supplied by the affected vessels are also damaged, or destroyed by lack of blood supply and oxygen.

The cause of vasculitis is not clearly understood, but...