What causes Raynaud's phenomenon with scleroderma?

If you have scleroderma, you may develop Raynaud's phenomenon. Raynaud's phenomenon occurs when your fingertips change color when you are cold. This is caused by a spasm in the small blood vessels in your fingers, and may be caused by having too much collagen in your blood vessel walls, a primary marker of scleroderma.

The spasm also causes the color changes in your fingers. Many people also have Raynaud's attacks in their toes. The color changes of a Raynaud's attack are an exaggeration of what happens normally when you expose your hands to the cold. Everyone will develop cold hands when they are exposed to cold temperatures for a long enough time. However, the normal cold response is a blotchy red and white pattern. The color changes of a Raynaud's attack-white then blue or purple-are very different.