Capillaritis, also known as pigmented purpuric dermatotis, refers to a group of related skin conditions that occur when the small veins beneath your skin leak blood. Here are four things you need to know about capillaritis.

What are the signs of capillaritis?

The main symptom of capillaritis is a purplish rash on the skin. The rash is made up of multiple macules with a purplish hue. Macules are flat areas of discoloration that may be small and distinct, but they can also grow into each other to form larger areas of discoloration.

This rash is quite distinct which allows the condition to be easily diagnosed by dermatologists. The rash tends to develop on the lower limbs and may be either chronic or relapsing.

What causes it?

Researchers know that capillaritis occurs when the capillaries, the tiny blood vessels beneath the skin, leak blood, but why this happens is still unknown. However, many diseases are suspected to play a role in the development of this condition. The following diseases may be connected to capillaritis, but more research needs to be done to understand how or why this occurs.

• Hypertension (high blood pressure);
• Diabetes;
• Venous stasis (slow blood flow in the veins of your legs);
• Thyroid dysfunction;
• Rheumatoid arthritis;
• Gout;
• Hepatitis;
• Depression.

Can dermatologists treat it?

Many treatments are available for capillaritis, but unfortunately, unsatisfactory outcomes are common. Your dermatologist may need to try a lot of treatments before one that helps you is found.

One treatment that may be used is corticosteroid therapy. You'll be given a cream that contains corticosteroids, a medication that reduces inflammation, to rub on your rash. This can help for some people, but it can't be used for a long period of time.

Other medications can also be used. Pentoxifylline, a medication used to treat peripheral artery disease, has been reported to be an effective treatment for some patients. Your dermatologist may also recommend taking antihistamines, a medication that is designed to treat allergies.

Is it common?

This condition is reported to be common in the United States. It can affect people of any race, though it tends to affect men more often than it affects women. People of any age can develop capillaritis, though some sub-types of the disease are more common among certain age groups.

If you have a purplish rash on your legs or feet, you may have capillaritis, and should see your dermatology physician right away.