Limited scleroderma, also known as CREST syndrome, is one subtype of scleroderma — a condition whose name means "hardened skin."
The skin changes associated with limited scleroderma typically occur only in the lower arms and legs, below the elbows and knees, and sometimes affect the face and neck. Limited scleroderma can also affect your digestive tract, heart, lungs or kidneys.
The problems caused by limited scleroderma may be minor. Sometimes, however, the disease affects the lungs or heart, with potentially serious results. Limited scleroderma has no known cure. Treatments focus on managing symptoms, preventing serious complications and improving quality of life.
While some varieties of scleroderma occur rapidly, signs and symptoms of limited scleroderma usually develop gradually. They include:
- Tight, hardened skin. In limited scleroderma, skin changes typically affect only the lower arms and legs, including fingers and toes, and sometimes the face and neck. Skin can look shiny from being pulled taut over underlying bone. It may become difficult to bend your fingers or to open your mouth.
Raynaud's phenomena. This condition occurs when small blood vessels in your fingers and toes spasm in response to cold or emotional stress, blocking the flow of blood. In most people, the skin turns white before becoming blue, cold and numb.
When circulation improves, the skin usually reddens and might throb or tingle. Raynaud's phenomena is often the first sign of limited scleroderma, but many people who have Raynaud's never develop scleroderma.
- Red spots or lines on skin. The swelling of tiny blood vessels near the skin's surface cause these small red spots or lines (telangiectasias). Not painful, they occur primarily on the hands and face.
- Bumps under the skin. Limited scleroderma can cause tiny calcium deposits (calcinosis) to develop under your skin, mainly on your elbows, knees and fingers. You can see and feel these deposits, which sometimes are tender or become infected.
- Swallowing difficulties. Limited scleroderma commonly causes problems with the tube that connects the mouth and stomach (esophagus). Poor functioning of the muscles in the upper and lower esophagus can make swallowing difficult and allow stomach acids to back up into the esophagus, leading to heartburn, inflammation and scarring of esophageal tissues.
When to see a doctor
Early detection of limited scleroderma can help prevent serious complications. See your doctor if you have any indications of the condition.
The cause isn't known, but limited scleroderma is believed to be an autoimmune disorder, in which your immune system turns against your body. The immune system appears to stimulate the production of too much collagen, a key component of connective tissue. This overproduction of collagen builds up in the skin and internal organs so that they don't function normally.
- Your sex. Women are far more likely to develop limited scleroderma than men are.
- Age. Limited scleroderma is more common between the ages of 30 and 50.
- Race. In the United States, limited scleroderma tends to be more severe in blacks and Native Americans than in whites.
- Genetic factors. If someone in your family has an autoimmune disease — such as lupus, rheumatoid arthritis or Hashimoto's disease — you have an increased risk of developing limited scleroderma.
- Exposure to toxins. Certain toxic substances — such as polyvinyl chloride, benzene, silica and trichloroethylene — might trigger scleroderma in people with a genetic predisposition to the disease.
The visible signs of limited scleroderma — tight, thick skin on your fingers, hands and face — can change your appearance; make everyday tasks, such as opening a jar or shaving, more difficult; and affect your speech. But the most serious complications tend to occur beneath your skin.
- Gastrointestinal problems. Changes in the functioning of esophageal muscles can cause difficulty swallowing and chronic heartburn. When limited scleroderma affects your intestine, it can cause constipation, diarrhea, bloating after meals, unintended weight loss and malnutrition.
- Ulcers on fingers and toes. Severe Raynaud's phenomena can obstruct blood flow to your fingers and toes, causing ulcers that can be difficult to heal. Also, abnormal or narrowed blood vessels combined with severe Raynaud's phenomena can lead to gangrene of fingers or toes, which might require amputation.
Lung damage. Limited scleroderma can cause a variety of problems with your lungs. In some cases, excess collagen collects in the tissue between the lungs' air sacs, making the lung tissue stiffer and less able to work properly.
Increased blood pressure in the arteries between your heart and lungs makes the heart work harder and eventually weakens it.
- Heart problems. Scarring of heart tissue can lead to abnormal heart rhythms (arrhythmias) and, in rare cases, to an inflamed heart muscle (myocarditis).
- Kidney problems. Although kidney damage is more common in other forms of scleroderma, it can occur in limited scleroderma. The first indication might be high blood pressure. Restricted blood flow to the kidneys can result in renal crises, which, if untreated, can lead to kidney failure.
- Dental problems. Severe tightening of facial skin can make it difficult to open your mouth wide enough to brush your teeth. Acid reflux can destroy tooth enamel, and changes in gum tissue may cause your teeth to become loose or even fall out.
- Dry eyes and mouth. Limited scleroderma can cause very dry eyes and mouth.