Mixed connective tissue disease, as first described in 1972, is an autoimmune response of body which have a high concentration of anti-U1 ribonucleoprotein antibodies, similarly seen in systemic sclerosis, systemic lupus erythematosus and polymyositis. Generally, the immune response is protective for the body but in autoimmune cases, the immune response strikes its own cell or tissues leads to pain and inflammation.
The knowledge of prevalence and incidence of mixed connective tissue disease epidemiologically are very little. However, the chances of the disease are more common in women about 80% instead of men which could occur at the age between 5 to 80 years.
What Are The Symptoms Of Mixed Connective Tissue Disease?
However, there are some clinical symptoms that suggest the positive cases of mixed connective tissue disease rather than another connective tissue disorder
More severe arthritis and risk of pulmonary hypertension (not related to lung fibrosis), which is distinguishable features of mixed connective tissue disease from both systemic sclerosis, systemic lupus erythematosus.
- Autoantibody Availability. Presence of specific autoantibodies like is anti-U1 ribonucleoprotein is another diagnosis when disease persists for long period.
- Raynaud Phenomenon. It is an early feature of mixed connective tissue disease in 90% of people; where the stress and cold response develop white and then the purplish-blue color of the figure due to vasoconstriction of vessels. Thus, the little warmness on the skin may dilate the vessels and turns it back in red in color.
- Myositis. The inflammatory myopathy is clinically and histologically similar to polymyositis and it is a symptom.
- Heart Disease. Approximately 20% of patients exhibit AV block and bundle branch abnormalities can be noted in ECG.
Some patients show pericarditis and myocarditis which could define the cardiac involvement and in a later stage, the pulmonary hypertension is one of the important symptoms in a patient of mixed connective tissue disease.
It has been documented to the acceleration of atherosclerosis due to dysfunction in lipid profile in individual have mixed connective tissue disease
Pulmonary Dysfunction– like dyspnea, dry cough, pleuritic chest pain is early and common symptom of the mixed connective tissue disease. Other additional symptoms related to the lung are
- Pleural effusions
- Pulmonary hypertension
- Obstructive pulmonary disease
- Diaphragmatic dysfunction
- Infections in lungs
- Interstitial lung disease (ILD)
- Alveolar hemorrhage
- Pulmonary vasculitis
- Thromboembolic disease
Kidney Disease. Protein urea and glomerulosclerosis are a renal associated complication in mixed connective tissue disease.
Hematological Problem. chances of anemia are another common problem with mixed connective tissue disease.
Mixed Connective Tissue Disease Causes
There are no specific causes for mixed connective tissue disease but there may be involvement of family history where the genetic component is triggered by an environmental event such as a virus, trauma, drugs or toxins are other possible causes.
Mixed Connective Tissue Disease Diagnosis
It can be performed by complete physical examination and threw by blood tests which determine whether certain antibodies are present in the blood such as Rheumatoid Factor (RF), Antibody tests specific to connective tissue disorders such as RNP, Anti-Nuclear Antibodies (ANA), and Immunoglobulins.
Mixed Connective Tissue Disease Treatment
Patients with mixed connective tissue disease are treated by family medicine doctors, general practitioners, and other specialists also involved in the treatment of these patients include rheumatologists, cardiologists, pulmonologists, nephrologists, and neurologists.
In general, treatment is initiated to suppress the symptoms of the inflammation present in the tissues by using anti-inflammatory and immunosuppressive medications. The nonsteroidal anti-inflammatory drugs (NSAIDs) class of drugs like indomethacin, piroxicam, and naproxen has potent anti-inflammatory properties via cyclooxygenase enzyme inhibition along with additional lysozyme, free radical stabilization.
Corticosteroids such as prednisolone are used as adjuvant therapy and inhibit phospholipase A2 enzyme which is responsible for catabolizing the phospholipid membrane and ultimately lead to reducing the production of arachidonic acid and prostaglandins.
An antimalarial compound like hydroxychloroquine is also used but the mechanism of action is not precisely known. However, it reduces interleukin-1 and B lymphocytes.
Immunosuppressants such as methotrexate, azathioprine, and cyclophosphamide are also one of the treatment options for mixed connective tissue disease which exert a beneficial effect by reducing the production of cytokine chemotaxis, the proliferation of immune inflammatory cells.
The symptoms of mixed connective tissue disease include fatigue, joint pain, pulmonary hypertension, swollen fingers and Raynaud’s syndrome.