Mixed Connective Tissue Disease
Mixed connective tissue disease (MCTD) is a rare autoimmune disorder featuring signs and symptoms of three different disorders: lupus, scleroderma and polymyositis. An autoimmune disorder is one in which the body’s immune system turns against the body it was designed to protect for unknown reasons.
No one knows exactly what causes the immune system to attack the body’s tissues in mixed connective tissue disease. Research suggests there may be a genetic component because the disease may occur more often in people with a family history of the disease. Exposure to certain viruses or chemicals in the environment may also play a role.
Symptoms of the different diseases that make up MCTD usually don’t begin at the same time. Early symptoms may include fatigue, mild fever, cold and numb fingers, swelling that gives fingers a sausage-like appearance and muscle and joint pain.
In the later stages of the disease, the heart, lungs, kidney or other organs may be affected.
Diagnosing MCTD can be difficult because the symptoms of the three diseases usually occur one after another over a long period of time. Doctors may suspect a diagnosis of mixed connective tissue disease after asking questions about the person's medical history and performing a physical examination. If so, blood tests will be ordered to measure levels of an autoantibody called anti-U1-RNP, whicht is found in high concentrations in people with MCTD.
Treatment for MCTD depends on which organs are involved and the severity of the disease. Some people need continuous treatment, while others need it only during periods of heightened disease activity, called flares.
Treatment may include corticosteroids to reduce inflammation and immunosuppressive drugs to suppress the immune system and its attack on healthy tissue. Other medications may be prescribed to treat or reduce the risk of certain complications of the disease.
In addition to medications prescribed by their doctors, people with MCTD can benefit from self management. This includes healthy lifestyle changes such as stopping smoking, reducing stress and protecting the hands from the cold.