Scleroderma: A Rare but Devastating Disease

Mar. 23 -- FRIDAY, July 27 (HealthDay News) -- The skin thickens and tightens, becoming deformed and unyielding. Then, the skin around the body's joints allows for less and less bending. Hands, elbows and knees all become stiff.

In worst cases, the hardening can reach into the internal organs, with potentially life-threatening results. The kidneys, lungs, heart, gastrointestinal tract and vascular system can become compromised, their normal processes hindered or halted as the organs grow rigid.

The disease is called scleroderma, and no one is sure what causes it or how it can be cured.

An estimated 200 to 300 people per million in the United States suffer from scleroderma, according to the American College of Rheumatology. Some 12 to 20 new cases per million are diagnosed annually.

Scleroderma is believed to be an autoimmune disease, in which the immune system turns against one's own body.

"Your body attacks itself," said Dr. Peter A. Merkel, an associate professor of medicine in the rheumatology section at Boston University School of Medicine, and a doctor with the school's scleroderma program.

It's not known what prompts the immune system attack, although researchers believe it is probably caused by a genetic predisposition interacting with some environmental stimulus.

"We know it's not likely to be a single cause, which makes research more challenging," said Carol Feghali-Bostwick, an assistant professor of medicine in the division of pulmonary, allergy and critical medicine at the University of Pittsburgh's Simmons Center for Interstitial Lung Disease.

The immune system is believed to stimulate cells called fibroblasts, causing them to produce too much collagen, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The collagen builds up thick connective tissue within the skin and internal organs that can interfere with their function.

Localized scleroderma can take the form of reddish patches of skin that thicken into firm, oval-shaped areas. The center of each patch becomes ivory colored with violet borders. The patches appear most often on the chest, stomach and back, but also can appear on the face, arms and legs. They sweat very little and have little hair growth.