Vasculitis refers to inflammation of blood vessels. This is a broad category of disease, and is often broken down into smaller subsections based on the size of the blood vessels that are involved.
Vasculitis can appear on the skin in many different forms. A classic dermatologic description of vasculitis is “palpable purpura,” which refers to the appearance of many purple/red bumps on the skin that can be easily felt. The rash appears red because blood has escaped the damaged blood vessel and entered into the skin to create a purple/red discoloration.
Vasculitis can occur for a number of reasons including infection, inflammation, or autoimmune conditions (where the body attacks its own blood vessels). Some known associations that occur with vasculitis include diseases such as lupus or rheumatoid arthritis. Viral infections can lead to vasculitis, such as hepatitis B or hepatitis C, as well as certain bacterial infections (example: streptococcus) and drug-related vasculitis. Often there is no identifiable cause, and this is referred to as “idiopathic” vasculitis.
Vasculitis can be characterized based on the size of the blood vessels that are affected.
- Small vessel vasculitis: The smaller blood vessels such as capillaries and superficial blood vessels are affected. Some examples include leukocytoclastic vasculitis and Henoch-Schonlein purpura.
- Medium vessel vasculitis: The medium-sized blood vessels such as arterioles can be affected. Some examples include lupus vasculitis and polyarteritis nodosa.
- Large vessel vasculitis: The large-sized blood vessels such as arteries and the aorta are affected. Some examples include Takayasu arteritis and giant cell arteritis. These conditions do not typically have a skin-based finding.
Vasculitis is a serious condition and should be evaluated by a physician, preferably in a hospital setting since the condition may affect different internal organ systems in the body and require various specialists. In general the goals of treatment will be to eliminate the triggering factor.
- Any medications that are identified as a cause for the vasculitis should be stopped.
- If the cause of the vasculitis is an infection, treatment of the infection can be helpful.
- In other cases, the vasculitis can be treated with antiinflammatory medications such as steroids. Evaluation by a physician is necessary to determine the cause and best treatment.
- In the case that the vasculitis is due to an autoimmune condition, immune suppressants may also be used. Some examples include cyclophosphamide, rituximab, methotrexate, azathioprine, and mycophenolate.