Vasculitis is a group of diseases that cause inflammation and damage to blood vessels. Learn about the different types, causes, symptoms, diagnosis, treatment, and complications of vasculitis from MedicineNet. Vasculitis is an umbrella term that describes subtypes of blood vessel inflammation in different parts of the body. Learn the role of antibodies. Vasculitis is a heterogeneous group of pathologies characterized by inflammation of vessels. They share common links of clinical, laboratory, and pathophysiologic features. The clinical and pathological features are variable and depend on the site and type of blood vessels affected.[1] Research has identified more than 30 kinds of vasculitis .[2] Vasculitis may present as a primary process or secondary to another underlying disease. Diseases in which vasculitis is a primary process are called ... Overview Vasculitis involves swelling and irritation, called inflammation, of blood vessels. The inflammation can cause the walls of the blood vessels to thicken. This thickening can narrow the vessels. If the narrowing restricts blood flow, it can damage organs and tissues. There are many types of vasculitis . Most of them are rare. Vasculitis might affect just one organ or several. The condition can be short-term or long lasting.