Vasculitis is considered to be an autoimmune disease wherein the immune system causes inflammation of the blood vessels. The disease can be acute or chronic. There are many types of vasculitis, which mainly occurs in rare diseases. Vasculitis causes changes in blood vessels which decrease blood flow and oxygen to body tissues and vital organs. While the causes of vasculitis are often unknown, it can occur after an infection, another disease, or a reaction to medication when the immune system is triggered and attacks the vascular system. Genetics may also be a factor.

Signs and symptoms of vasculitis can vary but include red spots, lumps, or sores on the skin, rash, nerve problems (which may cause numbness or weakness in hands and feet), cough and difficulty breathing, fever, weight loss, and fatigue.

The treatment depends on the type of vasculitis, with the goal of stopping the inflammation. While some vasculitis may improve without treatment, some types require steroids, immunosuppressive drugs such as cyclophosphamide, methotrexate, azathioprine, newer drugs such as rituximab, or surgery.