Mixed connective tissue disease

The exact underlying cause of mixed connective tissue disease (MCTD) is currently unknown. It is an autoimmune disorder, which means the immune system mistakes normal, healthy cells for those that that body should "fight off." There are ongoing studies exploring how immune system dysfunction may be involved in the development of this condition.

Mixed connective tissue disease (MCTD) is often suspected after a physical examination reveals signs and symptoms associated with the condition. The diagnosis is supported by a blood test that shows high levels of antibodies associated with MCTD.

The role of genetics in the onset of mixed connective tissue disease (MCTD) is still unclear. Some people with MCTD have family members who are also affected by the condition. This suggests that in some cases, an inherited predisposition may contribute to the development of MCTD. People with an inherited or genetic predisposition have an increased risk of developing a certain condition due to their genes.

In general, the long-term outlook (prognosis) for people with mixed connective tissue disease (MCTD) is favorable, but it mostly depends on the signs and symptoms present in each person.

The overall 10-year survival rate of the disease is about 80%. Some people have symptom-free periods lasting for many years with no treatment. Despite treatment, the disease gets worse in about 13% of people and can cause potentially fatal complications in six to 12 years. The prognosis is worse for people with features of systemic sclerosis and/or polymyositis. Pulmonary hypertension is the most common MCTD-associated cause of death.

Mixed connective tissue disease (MCTD) has been reported in all races and does not seem to occur more often in any racial or ethnic population. The clinical signs, symptoms and manifestations of MCTD are similar among different ethnic groups. MCTD is more common in females, with a female to male ration of 3:1. MCTD may affect any age, but typical age of onset is between 15-25 years old.

There is currently no cure for mixed connective tissue disease (MCTD). However, treatments can help manage symptoms of the condition. For example, medications such as over-the-counter or prescription nonsteroidal anti- inflammatory drugs may help with inflammation and pain of the muscles or joints. Glucocorticoids may be recommended in certain situations, such as during disease flares or when complications arise (e.g., aseptic meningitis, myositis, pleurisy, pericarditis, and myocarditis). Some people with MCTD require long term use of immunosuppressant medications.

Additional medications may be prescribed based on the signs and symptoms present in each person. For example, if a person with MCTD has developed symptoms similar to those of lupus, medications typically prescribed for people with lupus may be recommended.

For additional information about the treatment of MCTD, visit the Mayo Foundation for Medical Education and Research Web site.