How is scleroderma classified?
Patients with scleroderma may develop either a localized or a systemic (widespread) form of the disease.
Localized scleroderma affects mainly the skin. It can affect skin in different areas of the body. It may also affect muscles and bone, but it does not affect internal organs. This form is usually not as severe as generalized scleroderma. People who develop localized scleroderma usually do not develop generalized scleroderma.
Morphea scleroderma happens when hard, oval-shape patches form on the skin. The patches are usually whitish with a purplish ring around them. They usually occur on the trunk, but can also occur on the face, arms, legs, and other parts of the body. Morphea often improves by itself, over time. In morphea scleroderma patches of hard skin form and can persist for years. Eventually, however, they may improve or even disappear. There is less than a 1% chance that this disorder will progress to systemic scleroderma.
Linear scleroderma is a line of thickened skin that occurs in areas such as the arms, legs, or forehead. It can occur in more than one area. The line can extend deep into the skin and affect the bones and muscles underneath it. This can affect the motion of joints and muscles, as well as the growth of the affected area. When the line forms a long crease on the head or neck, it is sometimes called en coup de sabre--the strike of a sword. Linear scleroderma usually occurs in childhood. Linear scleroderma causes bands of hard skin across the face or on a single arm or leg. Linear scleroderma may also involve muscle or bone. In rare cases, if this variant affects children or young adults, it may impair growth and cause severe deformities in the arms and legs.
In systemic scleroderma (also called generalized scleroderma) the organs of the body, widespread areas of the skin, or both may be involved. This form of scleroderma has two primary variants: limited (also called CREST syndrome) or diffuse scleroderma. Both forms are progressive, although most often the course in either one is slow. Generalized scleroderma affects many parts of the body. It can affect the skin as well as internal body parts, such as blood vessels, the digestive system (esophagus, stomach, and bowel), the heart, lungs, kidneys, muscles, and joints. The severity of this form depends on the organs affected and how much they are affected. In rare cases, scleroderma may affect only some internal system, leaving the skin and joints untouched.
There are two types of generalized scleroderma: limited (also called the CREST syndrome) and diffuse. CREST stands for a combination of symptoms: Calcinosis, Raynaud's phenomenon, Esophageal dysfunction, Sclerodactyly, and Telangiectasia. This type, also known as limited scleroderma, usually has a slow onset, with the first symptoms appearing 10 to 20 years before the full syndrome occurs. It usually affects the skin on the face, fingers and hands. Later on, it may affect internal organs, such as the esophagus (the tube leading from mouth to the stomach), the lungs and bowels. Diffuse occurs throughout the body. It usually affects the skin as well as other body parts, such as the lungs, kidneys, heart, bowels, blood vessels and joints. Depending on the areas affected, this type can cause problems such as high blood pressure, muscle weakness, trouble swallowing, or shortness of breath. Diffuse scleroderma may progress slowly in some people and more rapidly in others. However, with proper management, it can usually be controlled.