Trained in dentistry, Sree is currently studying lab sciences. She enjoys researching various health topics and writing about her findings.
Mixed connective tissue disease is an autoimmune disease that was first characterized in 1972. It is also called Sharp's syndrome and is commonly referred to in its acronym, MCTD. As the name suggests, the disease is a combination of several disorders that affect various connective tissues in the body. Lupus, scleroderma and polymyositis are the primary disorders whose symptoms affect individuals with MCTD. Like many autoimmune diseases, MTCD progresses over time. That is, some of the symptoms associated with the condition do not develop simultaneously but instead occur in sequence over a long period of time. Because of these traits, MTCD often prove difficult to diagnose, while treatment is limited to the management of symptoms and the extension of mixed connective tissue disease life expectancy.
Mixed Connective Tissue Disorders
As mentioned, MTCD is a combination of different disorders that affect connective tissues in the body. Therefore, to understand the condition, it is important to identify the most common disorders that affect the connective tissues, which are structures that hold cells in the body together.
Most disorders of the connective tissue are strictly obtained through genetic inheritance. There is no known environmental factor that can lead to the development of any such disease, which includes Marfan syndrome and Ehlers-Danlos syndrome. However, a few connective tissue diseases are related to the overactivity of the immune system. Rheumatoid arthritis, systemic lupus erythematosus, scleroderma, dermatomyositis and polymytosis are immune system-related conditions that MCTD patients exhibit.
Because mixed connective tissue disease is an overlap disease, any combination of connective tissue disorders can affect an individual with this condition. However, the three primary disorders seen to affect MCTD patients are systemic lupus erythematosus, scleroderma and polymyositis. Each of the component disorder has its own classic features that make diagnosis possible. Abnormalities in blood characteristics and antibody patterns also help identify the existence of the condition and individual connective tissue disorders that compose it.
Causes and Risk Factors
There is no known causative factor to mixed connective tissue disease other than genetic predisposition. Specifically, the gene HLA-DR4 is seen to be associated with the condition. As an autoimmune disease, MCTD is a degenerative disorder that is caused by the overactivity of the immune system. In this condition, like in any of its kind, the immune system mistakes healthy cells for foreign bodies that need to be destroyed. Thus, normal cells deteriorate and eventually die. In the case of MCTD, the immune system attacks the fibers that provide structure and support for the body.
Likewise, there are no definitely identified risk factors for mixed connective tissue disease. The disease can occur to a person of any age, sex or race. It is however seen that MCTD is most common among females under the age of 30. The general mixed connective tissue disease life expectancy, therefore, is beyond this age.
Signs and Symptoms of Mixed Connective Tissue Disease
The signs and symptoms of mixed connective tissue disease vary greatly among different patients because the combination of disorders present and their corresponding severity also vary from one individual to another. Depending on the primary disorders, the dominant features of MCTD range from muscle weakness, thickening of the skin (sclerodactyly), and to kidney disease.
Muscle weakness, in particular, is a dominant characteristic of MCTD if the leading connective tissue disorder is polymyositis. Kidney disease and arthritis are meanwhile common prevalent symptoms among patients with a dominant systemic lupus erythematosus. The last of the three primary disorders—scleroderma—once prevalent, presents sclerodactyly and discoloration of the fingers.
Other than these classic features, MCTD also exhibit a broad list of symptoms. A general feeling of malaise is typical among patients with this condition, as they experience fatigue and mild fever with relative frequency. Raynaud's phenomenon, wherein the fingers feel cold and numb, is another common indication of MCTD. This symptom is also characterized by the discoloration of the fingers in response to certain stimuli. The fingers and sometimes the toes can turn white, purplish blue or red depending on the situation and the state of blood vessels. Aside from this, the fingers of mixed connective tissue disease patients can also appear sausage-like, as in its size, due to the characteristic swelling brought about by the condition. Muscle pain can also result from MCTD, as well as the swelling of the joints, which also cause pain. There may also be deformities formed in the joints, such as the case in rheumatoid arthritis.
Diagnosis, Treatment and Mixed Connective Tissue Disease Life Expectancy
Diagnosis of MCTD begins with a physical exam that will determine the presence of the classical signs and symptoms, such as swollen fingers and joints. Blood and antibody tests are carried out to confirm the condition. Positive individuals have high amounts of anti-nuclear antibody (ANA) and anti-RNP antibody in their blood. To distinguish MCTD from its component disorders, doctors can check for antibodies such as dsDNA and sc170, which are typically absent in MCTD patients but present in those with a single connective tissue disorder, particularly systemic lupus erythematosus and scleroderma.
The treatment of MCTD is largely dependent on the dominant disorders and their corresponding symptoms. The outlook and the mixed connective tissue disease life expectancy consequently depend on this variable. For some cases, treatment, which takes the form of medication, is only necessary during flares or when the symptoms become worse. In other, milder cases, treatment may not even be required. On the other hand, continuous medication is necessary for more severe cases of mixed connective tissue disease.
Alleviating the symptoms is the primary objective of MCTD therapy. Tissue inflammation is addressed through anti-inflammatory drugs and immunosuppressive medications. Corticosteroids such as prednisone, and nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to control immune function and suppress inflammation. Antimalarial and cytotoxic drugs are also used to treat the same symptoms. In some cases, physical therapy may be prescribed by the attending physician. For Raynaud's phenomenon in particular, a certain exercise is recommended to minimize the symptoms. Meanwhile, complications that may arise, such as kidney disease, are addressed through appropriate therapy. The severity of such problems and the action taken towards them often dictate the mixed connective tissue disease life expectancy among patients.
There are also a few home remedies and lifestyle changes that can help in the alleviation of MCTD symptoms. Protecting the hands from the cold can help reduce the effects of Raynaud's phenomenon, while quitting smoking and reducing stress can also do the same.
Prognosis of MCTD
The outlook of MCTD is generally worse than that of single connective tissue disorders, such as systemic lupus erythematosus. Even in the presence of prednisone treatment, the condition tends to continuously deteriorate the patient's body. This is because MCTD is a progressive autoimmune disease that naturally develops into worse disorders or creates more complicated and fatal symptoms. One common condition met by patients with MCTD is progressive systemic sclerosis, which has a poor prognosis.
In general, however, mixed connective tissue disease life expectancy varies highly, as there are many factors that need to be considered. The organs affected by the condition and its complications, the severity of the connective tissue disorders that compose MCTD and the course of treatment taken are all determinants of whether or not a patient survives for a long period of time. With appropriate action, for instance, a patient can live for 10 more years after diagnosis. If fact, 80 percent of MCTD patients that undergo necessary medication and treatment enjoy such prognosis.
Mixed connective tissue disease life expectancy is decidedly short, and death is inevitable in most cases. However, up to 30 percent of cases are mild, and there are individuals that experience remission. This is particularly true of patients with no anti-RNP antibody in their blood.
Anita Hasch from Port Elizabeth on March 03, 2018:
Read your hub again. So interesting
UNCLE HEALTH on February 25, 2018:
Anita Hasch from Port Elizabeth on November 16, 2016:
Very interesting and informative hub Sree.
Stacey Widdoss on June 18, 2016:
I think I just got this disorder.Litteraly today.I am 14 years old.Yesterday I put on black nailpolish and took it off because right when I put it on my middle finger started to curve.The next day(more like 30 minutes ago)my fingers are all bent down and I can't make them go straight.And my arms hurt really bad so much that I am crying.I'm scared after reading this.I can't even hold a pencil.But I could 4 hours ago.
Nicky on September 15, 2015:
I was just recently diagnosed with MCTD borderline im a bit confussed about being borderline either ur pregnent or ur not lol and everwhere I search doesnt have anything about being borderline MCTD so if some one has any thing they can share it would be very helpful to me I sincerly welcome it Thank You
Sree Lakshmi (author) on September 12, 2015:
Sorry Jennifer, God bless you!
Jennifer on September 11, 2015:
I was diagnosed when I was 12 with mixed connective tissue disorder, I was also diagnosed at 9 with Chronic arthritis in every joint!! Also in my early 20's was diagnosed with fibromyalgia. I've been through a lot!! And also Had a heart attack at age 34 right before my Birthday, But I keep fighting!