DEAR DOCTOR K: My father recently saw his doctor, complaining of fever, fatigue, joint pain and rashes. His doctor suspects vasculitis. What is vasculitis?
DEAR READER: Vasculitis is an inflammation of the blood vessels. This inflammation can be severe enough to reduce blood flow to tissues and organs. We don’t know for sure what causes it, but scientists believe it is an autoimmune disease. For some reason, the immune system mistakenly attacks the blood vessels, causing them to become inflamed. Under the microscope, you can see immune system cells next to the walls of blood vessels, and the walls have been damaged (presumably by the attack).
There are many different types of vasculitis, affecting blood vessels of different sizes and in different locations. Following are some of the types of vasculitis:
• Giant cell arteritis (temporal arteritis) affects medium to large arteries, including those around the scalp, face and eyes. This type also affects the aorta as it branches from the heart, up into the neck and head.
• Takayasu arteritis affects the body’s biggest artery, the aorta, and its main branches.
• Polyarteritis nodosa affects small- to medium-sized blood vessels, especially in the skin, intestines, kidneys and nerves.
• Kawasaki disease is particularly likely to involve the arteries of the heart. It occurs mainly in children and can cause fatal heart attacks in young children.
• Hypersensitivity vasculitis affects the smallest blood vessels, especially those in the skin. It is triggered by an allergy, particularly to a drug.
The most accurate way to diagnose vasculitis is with a tissue biopsy.
Before a biopsy, however, the doctor is likely to do some less invasive tests. These may include blood tests to check for inflammation, immune system activity, and liver and kidney function. Urine analysis may also be done to evaluate possible kidney problems.
The main treatment for most types of vasculitis is prednisone. This corticosteroid works by reducing inflammation. Additional treatments depend on the form of vasculitis.
The good news is that most cases of vasculitis can be treated successfully.