Causes
The exact cause of scleroderma is unknown. Scleroderma is a rare autoimmune disease, a disease in which the immune system attacks its own healthy cells, causing damage.
Normally, the immune system helps the body deal with infection and injury. People with scleroderma produce too much collagen, a protein that makes up connective tissue in tendons and ligaments. Depending on the type of scleroderma a person has, the extra collagen is deposited in either the skin or in other organs in the body, or both, which causes hardening of the tissues.