What causes systemic sclerosis?
Systemic sclerosis develops because of changes that occur in the body's connective tissues. These tissues lie under the surface of the skin and also in and around the body's internal organs and blood vessels.
Systemic sclerosis leads to too much fibrous connective tissue, which is similar to scars that form after an injury. Scar tissue contains a protein called collagen, which is essential to help hold the body together. However, having too much collagen can cause the body's tissues to stiffen and thicken.
We don't yet know exactly why some people produce too much scar-like connective tissue. The immune system – which normally fights off infections – appears to be overactive and attacks healthy body tissues instead. This is thought to be due to a mix of genetic and environmental factors.
Although the genes we inherit from our parents can affect our risk of developing systemic sclerosis, the condition isn't passed directly from one generation to another. Systemic sclerosis isn't contagious so it can't be caught from somebody else.