Systemic sclerosis is a rare, progressive disease that leads to hardening and tightening of the skin and connective tissues. It usually begins with a few dry patches of skin on the hands or face that begin getting thicker and harder. These patches then spread to other areas of the skin. In some cases, systemic sclerosis also affects the blood vessels an internal organs. Systemic sclerosis is one of a group of arthritic conditions called connective tissue disorders, a person's antibodies are directed against their own tissues.