Causes

The exact cause of vasculitis isn't fully understood. Some types are related to a person's genetic makeup. Others result from the immune system attacking blood vessel cells by mistake. Possible triggers for this immune system reaction include:

• Infections, such as hepatitis B and hepatitis C
• Blood cancers
• Immune system diseases, such as rheumatoid arthritis, lupus and scleroderma
• Reactions to certain drugs