Polymyositis is quite rare, but serious. This pathology belongs to the group of systemic diseases. The disease is characterized by damage to smooth and skeletal muscles, often combined with damage to the skin (in this case, the disease is called dermatomyositis). This article is devoted to the symptoms of polymyositis, diagnosis and treatment of this pathology.
Causes of disease
The etiology of the disease is little studied. Until now, the main cause of polymyositis, unfortunately, remains unknown.
There is an opinion that the main triggering factor is some past viral infection. The likelihood of developing polymyositis (the symptoms of which are described in this article) is much higher if the patient has ailments caused by parasites. It is believed that one of the "causal" factors is an indirect reaction of the body's immune defenses to viral antigens.
In addition, the following can provoke manifestations of the disease:
- Various injuries.
- Drug allergies.
- Hypocooling/overheating.
- Prolonged exposure to intense sunlightradiation.
- Pregnancy.
In about a third of patients, the disease is accompanied by the formation of a variety of neoplasms and may be a consequence of the toxic effects of cancer cells on the muscles. Another option for the onset of the disease is the result of immunopathological reactions due to the commonality of myocytes and tumor antigens, which the body perceives in the same way and tries to destroy.
Risk groups
Theoretically, anyone can get sick with polymyositis, regardless of gender and age. However, according to statistics, women are more often affected than men. It has been established that the majority of cases are children aged 5-15 and adults aged 40-60.
Classification
According to the location of the process and the symptoms present, polymyositis is divided into the following types:
- Primary (ideopathic) form of polymyositis. It develops slowly, it is more typical for women. In this case, the proximal muscles of the neck and limbs are damaged. Patients complain of difficulty in climbing stairs, combing, muscle tension and soreness. Sometimes arthralgia is also present. In severe cases, muscles atrophy and dysphagia develops.
- Myositis with inclusion. This variety is rarely diagnosed. Accompanied by damage to the distal segments of the limbs.
- Juvenile (children's) form. The main manifestation is calcification (deposition of calcium s alts) in and under the skin. With the progression of the process, atrophy and contractures appear, vessels are affected (up to vasculitis and thrombosis) and the gastrointestinal tract, a pronounced pain syndrome, ulcerations, perforations and bleeding occur.
- In combination with autoimmune systemic pathologies. In this case, polymyositis acts as a complication of SLE, RA, Sjögren's disease or scleroderma.
- Primary dermatomyositis (ideopathic). The symptomatology of this form is represented by the occurrence of various rashes (dermatitis, erythema) on the face, in the area of the joints of the fingers, back and limbs. Stomatitis, conjunctivitis and pharyngitis are often present.
- Polymyositis in malignant neoplasms. Most often found two years after the malignancy of the process. This form is typical for elderly patients with cancer of the testicles, prostate or breast, lungs, intestines, as well as for those suffering from lymphomas.
Clinical picture
This pathology (both for adults and children) is characterized by a subacute onset of the process. At the same time, manifestations of damage to the muscles of the shoulders and pelvis are considered the first symptoms of polymyositis.
Further, symptoms of lesions of internal organs (lungs, gastrointestinal tract and heart) join. Approximately 15% of patients have articular syndrome.
Patients are often interested in what symptom is most characteristic of polymyositis. As a rule, manifestations of the muscular syndrome come to the fore in this disease. Let's talk about it in more detail.
Muscle Syndrome
Characterizedmuscle pain that occurs during movement, palpation, and in some cases at rest. Along with soreness, muscle weakness increases, preventing the patient from performing elementary movements actively and in full. The patient is unable to sit down, hold objects in his hands, stand up, tear his head off the pillow, and so on.
The muscles affected by the disease thicken and swell. Later, they undergo atrophy, myofibrosis, and, in some forms, calcification. Such changes can lead to complete immobilization of the patient.
Muscular syndrome implies the presence of lesions and smooth muscles of the esophagus, larynx, pharynx. In this case, swallowing disorders (dysphagia) and speech changes (dysarthria) occur. If the process spreads to the mimic muscles, the patient's face becomes similar to a mask, to the muscles of the eyes - the occurrence of ptosis, strabismus and diplopia.
Articular syndrome
Indicates damage to the joints of the hand and wrist.
The ankle, shoulder, knee and elbow joints are much less frequently injured. At the same time, obvious characteristic signs of the inflammatory process in the joint are observed: hyperemia and swelling of the skin (sometimes calcifications are found in it), restriction in movements. However, the deformation of the joint with polymyositis does not occur.
Changes in internal organs
When polymyositis most often occurs lesions of the digestive tract, manifested by the following symptoms: anorexia,bowel obstruction, diarrhea/constipation, abdominal pain, bleeding erosions, perforations or ulcers.
The result of failure of the respiratory muscles and throwing food into the respiratory tract during choking is hypoventilation and, as a result, the development of pneumonia.
Damage to the organs of the cardiovascular system manifests itself in the form of arrhythmia, hypotension, Raynaud's syndrome, heart failure and myocarditis.
Course of illness
The course of polymyositis can be acute, subacute (more often) and chronic.
In the case of an acute course, the disease manifests itself with intoxication and fever, muscle lesions progress rapidly, dysarthria and dysphagia occur. In a short time, the patient becomes immobilized. If therapy is not carried out, the condition deteriorates rapidly. There is also a fatal outcome.
Polymyositis with subacute course is characterized by undulating changes in the patient's condition: periods of deterioration alternate with improvements. Despite the seeming periodic improvement, muscle weakness increases and damage to internal organs joins.
The chronic course of the disease is considered the most favorable and is characterized by the defeat of only some muscle groups, due to which patients remain able to work for a long time.
Diagnostic measures
If polymyositis is suspected (with the symptoms described above), the patient should consult a rheumatologist, neurologist, gastroenterologist, pulmonologist and cardiologist.
Clinical study resultsblood indicates the presence of inflammation (leukocytosis and accelerated ESR). Blood biochemistry reveals signs of damaged muscle tissue (increased levels of aldolase, CPK, ALT, AST). With polymyositis, these data are used to determine the degree of inflammation activity in muscle tissues. Approximately 20% of patients have antinuclear antibodies. Even more rarely, rheumatoid factor is detected in the blood of patients.
In order to exclude the presence of other neuromuscular pathologies, electromyography is prescribed. Confirmation of pathological changes in muscle tissues will be:
- Low amplitude action potential.
- Spontaneous fibrillations.
- Increased excitability.
The most informative technique confirming the presence of polymyositis is the histology of muscle fibers. To take the material, a biopsy of the quadriceps or biceps of the shoulder is used. At the same time, changes characteristic of polymyositis are detected: infiltration of muscle tissue and vascular walls by lymphocytes, the presence of vacuoles (cavities) between fibers, degenerative or necrotic changes.
For the diagnosis of the state of somatic organs, an X-ray of the lungs, ultrasound of the heart and gastrointestinal tract, gastroscopy and ECG are prescribed.
Pathology Therapy
Treatment of polymyositis comes down to eliminating the inflammatory process and maintaining a stable remission.
Basic therapy - glucocorticosteroid drugs. At the beginning of treatment, the dosage of "Prednisolone" is 40-60 mg / day,further reduced to 10-20 mg/day.
In cases where the treatment does not bring the desired effect (that is, there is no improvement in the condition and blood counts), immunosuppressants are prescribed (for example, Methotrexate). These drugs can be administered either orally or intramuscularly. Contraindications to the use of "Methotrexate" are: renal / liver failure, pathological changes in blood clotting.
Immunosuppressants "Cyclophosphamide", "Cyclosporine", "Azathioprine", "Chlorambucil" are less popular for polymyositis, but they are also prescribed in some cases.
Before the inflammatory reactions subside, the patient's physical activity is sharply limited.
If polymyositis is combined with vasculitis, the patient is prescribed lymphocyto- and plasmapheresis.
Forecasts
The most unfavorable prognosis is the acute form of polymyositis, the causes and symptoms of which we discussed above. Aspiration pneumonia or cardiopulmonary failure resulting from this is most often the cause of death.
Childhood of the patient worsens the prognosis of polymyositis (symptoms and treatment for this category of patients are the same as for adults). The difference lies in the dosage of drugs, which must be determined by the attending physician. The steady and rapid progression of the pathology almost always leads to immobilization of the child.
Chronic course is the most favorable for both life and further work capacity.
