Systemic sclerosis is a rare, chronic disorder characterized by degenerative changes and scarring in the skin, joints, and internal organs and by blood vessel abnormalities.
Swelling of the fingers, intermittent coolness and blue discoloration of the fingers, joints freezing in permanent (usually flexed) positions (contractures), and damage to the gastrointestinal system, lungs, heart, or kidneys may develop.
People often have antibodies in the blood characteristic of an autoimmune disorder.
No treatment changes the course of the disorder.
Symptoms and organ dysfunction are treated.
Systemic sclerosis causes an overproduction of collagen and other proteins in various tissues. The cause is not known. The disorder is 4 times more common among women and most common among people aged 20 to 50. It is rare among children. Symptoms of systemic sclerosis may occur as part of mixed connective tissue disease (see Mixed Connective Tissue Disease (MCTD)), and some people with mixed connective tissue disease develop severe systemic sclerosis. Systemic sclerosis can occur in limited forms, for example, sometimes affecting just the skin or mainly only certain parts of the skin or as CREST syndrome (see CREST syndrome). However, systemic sclerosis often causes damage that is widespread throughout the body (called diffuse or generalized systemic sclerosis).
The usual initial symptom of systemic sclerosis is swelling, then thickening and tightening of the skin at the ends of the fingers. Raynaud phenomenon, in which the fingers suddenly and temporarily become very pale and tingle or become numb, painful, or both in response to cold or emotional upset (see Raynaud Syndrome), is also common. Fingers may become bluish or white. Heartburn, difficulty in swallowing, and shortness of breath are occasionally the first symptoms of systemic sclerosis. Aches and pains in several joints often accompany early symptoms. Sometimes inflammation of the muscles (polymyositis—see Polymyositis), with its accompanying muscle pain and weakness, develops.
Systemic sclerosis can damage large areas of skin or only the fingers (sclerodactyly). Sometimes systemic sclerosis tends to stay restricted to the skin of the hands. Other times, the disorder progresses. The skin becomes more widely taut, shiny, and darker than usual. The skin on the face tightens, sometimes resulting in an inability to change facial expressions. Sometimes dilated blood vessels (telangiectasia often referred to as spider veins) can appear on the fingers, chest, face, lips, and tongue, and bumps composed of calcium can develop on the fingers, on other bony areas, or at the joints. Sores can develop on the fingertips and knuckles.
Scarring commonly damages the lower end of the esophagus (the tube connecting the mouth and stomach). The damaged esophagus can no longer propel food to the stomach efficiently. Swallowing difficulties and heartburn eventually develop in many people who have systemic sclerosis. Abnormal cell growth in the esophagus (Barrett esophagus—see see Risk Factors) occurs in about one third of people, increasing their risk of esophageal blockage (stricture) due to a fibrous band or their risk of esophageal cancer. Damage to the intestines can interfere with food absorption (malabsorption) and cause weight loss.
Systemic sclerosis can cause scar tissue to accumulate in the lungs, resulting in abnormal shortness of breath during exercise. The blood vessels that supply the lungs can be affected (their walls thicken), so they cannot carry as much blood. Therefore blood pressure within the arteries that supply the lungs can increase (a condition called pulmonary hypertension—see see Pulmonary Hypertension). Systemic sclerosis can also cause several life-threatening heart abnormalities, including heart failure and abnormal rhythms.
CREST syndrome, also called limited cutaneous systemic sclerosis, involves more peripheral areas of the skin (not the trunk). It typically does not affect the kidneys and lungs directly but may eventually increase pressure in the arteries that supply the lungs (called pulmonary hypertension). Pulmonary hypertension can cause heart and lung failure. CREST syndrome is named for its symptoms: Calcium deposits in the skin and throughout the body, Raynaud phenomenon, Esophageal dysfunction, Sclerodactyly (skin damage on the fingers), and Telangiectasia (dilated blood vessels or spider veins). In CREST syndrome, Raynaud phenomenon can be severe enough to permanently damage the fingers and toes. The drainage system from the liver may become blocked by scar tissue (biliary cirrhosis), resulting in liver damage and jaundice.
A doctor suspects systemic sclerosis in people who have Raynaud phenomenon, typical joint and skin changes, or gastrointestinal, lung, and heart problems that cannot be otherwise explained. A doctor diagnoses systemic sclerosis by the characteristic changes in the skin, the results of blood tests, and presence of damage to internal organs. The symptoms may overlap with those of several other disorders, but the whole pattern is usually distinctive. Laboratory tests alone cannot identify systemic sclerosis because test results, like the symptoms, vary greatly. However, antinuclear antibodies are present in the blood of more than 90% of people with systemic sclerosis. An antibody to centromeres (part of a chromosome) is often present in people who have CREST syndrome. A different antibody (called anti-topoisomerase) is often present in people with the more diffuse generalized form.
Doctors may do pulmonary function testing, computed tomography (CT) of the chest, and echocardiography, sometimes periodically, to detect heart and lung problems.
Sometimes systemic sclerosis worsens rapidly and becomes fatal. At other times, it affects only the skin for decades before affecting internal organs, although some damage to internal organs (such as the esophagus) is almost inevitable. The course is unpredictable. Overall, about 65% of people live for at least 10 years after the diagnosis is made. The prognosis is worst for those who have heart, lung, or, particularly, kidney damage. The prognosis for people who have CREST syndrome tends to be more favorable.
No drug can stop the progression of systemic sclerosis. However, drugs can relieve some symptoms and reduce organ damage. Nonsteroidal anti-inflammatory drugs (NSAIDs—see see Nonopioid Analgesics : Nonsteroidal Anti-Inflammatory Drugs) help relieve joint pain but may cause gastrointestinal problems. If the person has weakness because of polymyositis, corticosteroids may be needed. Drugs that suppress the immune system, such as methotrexate, mycophenolate mofetil, cyclophosphamide, and azathioprine, may help some people whose lungs are affected. Some people may need a lung transplant. Doctors treat severe pulmonary hypertension with the drugs bosentan or epoprostenol.
Heartburn can be relieved by eating small meals, taking antacids, and using proton pump inhibitors, which block stomach acid production. Sleeping with the head of the bed elevated often helps. Areas of the esophagus narrowed by scar tissue can be surgically widened (dilated). Tetracycline or other antibiotics can help prevent malabsorption of food caused by excessive growth (overgrowth) of bacteria in the damaged intestine. A calcium channel blocker (such as nifedipine) may relieve the symptoms of Raynaud phenomenon but may also increase the reflux of stomach acid. The drugs bosentan, sildenafil, tadalafil, and vardenafil are other alternatives for severe Raynaud phenomenon. Drugs for high blood pressure, particularly angiotensin-converting enzyme (ACE) inhibitors, are useful in treating kidney disease and the rise in blood pressure.
People should dress warmly, wear gloves, and keep their head warm. Physical therapy and exercise can help maintain muscle strength but cannot totally prevent joints from freezing in contractures.