Myopathy: symptoms, principles of diagnosis and treatment

Myopathy is a heterogeneous group of diseases, based on the primary damage to muscle tissue.

Another term for myopathy is myodystrophy, which is more often used in the designation of hereditary myopathies.

Primary damage to muscle cells can occur under the influence of various etiological factors (heredity, metabolic disorders, bacteria). On this fact, the accepted classification of myopathies is based.

Classification

The leading etiologic factor of many types of myopathies is heredity.

There are the following types of myopathies:

1. Progressive muscular dystrophy.

• Myocardium Duchenne.
• Bekker's myopathy.
• Myopathy of the Landusi-Dezherin.
• Myopathy of Emery-Dreyfus.
• Limb and waist form of progressive muscular dystrophy.
• Ophthalmopharyngeal form.
• Distal myopathies (Myosha myopathy, myopathy Welander, etc.)

1. Congenital muscular dystrophies and structural myopathies.
2. Metabolic myopathies (mitochondrial myopathies, endocrine).
3. Inflammatory myopathy.

The classification indicates the most common myodystrophy, but this is not a complete list.

Symptoms

The main symptom of all myopathies is muscle weakness. The proximal parts of the limbs (shoulder girdle, shoulders, hips, pelvic girdle) are drawn more often than the rest of the body.

Each type of muscular dystrophy proceeds with the defeat of certain muscle groups, which is important when making a diagnosis. Muscles are affected symmetrically. If weakness manifests itself in the muscles of the pelvic girdle and legs, then such a person in order to get up off the floor, uses stage lifting: hands on the floor, then on your knees, then rises with a support on the furniture (bed, sofa). It seems that he "climbs by himself." It is difficult to climb stairs or uphill. There is a need to use hands when lifting. With the development of weakness in the hands there are difficulties in combing the hair. With the weakness of the muscles supporting the spine, there is an increased inflexion of the lower back forward. The defeat of the scapular muscles results in the lagging of the lower edge of the scapula from the back ("winglike" scapula). Muscles of the face suffer less often than others and only with some myopathies. In humans, ovulation of the upper eyelids (ptosis) occurs, the upper lip descends, articulatory speech disorders occur, swallowing disorders. With weakness in the hands of a person, difficulties arise in performing highly differentiated work (writing, playing musical instruments, turning things, etc.). The weakness of the feet is manifested by the formation of a hollow foot, a spanking gait.

Over time, muscle tissue disintegrates, appearing atrophied muscles. Against the background of muscle atrophy, connective tissue proliferation occurs, which creates a false impression of trained, pumped muscles - muscle pseudohypertrophy. In the joints are formed contractures, contraction of the muscle-tendon fibers, which leads to a limitation of mobility in the joints, painful sensations.

For most myopathies, the clinical picture has the same signs. Let us dwell on the most frequent myopathies, which differ in the age-related debut of the disease, the rate of progression of the process, the cause of the onset.

Progressing muscular dystrophies

These are hereditary diseases, which are based on the death of muscle fibers with the gradual replacement of fat tissue. This group is characterized by rapid progression of the process, which leads to disability of the person.

1. Myocardia Duchenne and Becker.

Myodystrophy has a similar clinical picture. Diseases are recessive and transmitted with the X-chromosome, so only boys are ill. At the heart of the pathology is a violation of the structure (Becker's myopathy) or completely absence (myopathy Duchenne) special protein - dystrophin, which is involved in the work of neurons, muscle fibers of the skeleton, heart. Pathological changes in the structural protein lead to necrosis of muscle cells - atrophy. Duchenne's myopathy occurs several times more often than Becker's myopathy. The debut of Duchenne's myodystrophy occurs at an early age (age from 3 to 7 years). The first symptoms are nonspecific, and parents at first often refer them to the nature of the character: lack of mobility in comparison with their peers, passivity in games. Pseudohypertrophic muscles do not cause suspicion. Over time, the clinical picture worsens: the child ceases to rise from the floor without support, there is a duck walk because of the weakness of the muscles of the pelvic girdle. There is walking on your socks, because the Achilles tendons change and prevent you from getting up on your heels. Intellect is reduced.

The clinical course is rapidly progressing and by the age of 9-15 the child loses the ability to move independently, disability occurs. On examination, contractures (contractions) in ankle joints are revealed. Muscles of the hips, pelvic girdle, back, upper parts of the arms atrophy. Often in children, atrophy is not noticeable due to the development of subcutaneous fat. Osteoporosis, dilated cardiomyopathy and respiratory failure are associated. The child wakes up with a feeling of fear, suffocation, lack of air against the background of a decrease in the vital capacity of the lungs and the development of respiratory failure.

The lethal outcome occurs in 20-30 years from respiratory or heart failure.

Becker's myopathy proceeds more gently. The clinical picture is basically similar to the clinic of Duchenne's myopathy, but the debut of the disease occurs at a later age (11-21 years). A person loses the ability to move independently at a later age (after 20 years). The defeat of the heart is less common, compared with Duchenne's myodystrophy. The intellect is saved.

1. Myopathy Landuzi-Dezherina.

The disease affects the muscles of the shoulder girdle and shoulders, as well as the facial muscles of the face. The debut of myodystrophy falls on the second decade of human life. Initially, there is weakness and atrophy in the muscles of the shoulder girdle, which is manifested by the spacing of the scapula from backs ("pterygoid" scapula), the shoulder joints are turned inward, the thorax cramps into the antero-posterior size. Gradually, the muscles of the face are involved in the process: speech becomes illegible, the upper lip is lowered ("Lips of a tapir"), a person's smile becomes horizontal without lifting the corners of his lips (smile Mona Lisa). In some people, atrophy affects the muscles of the legs, especially the legs. A characteristic symptom is asymmetric muscle atrophy. Pseudohypertrophy does not always happen. Contractures of the joints are less pronounced compared to Duchenne's myopathy.

Muscle weakness and atrophy are combined with dilated cardiomyopathy, retinal detachment, and hearing loss. In some patients, motor activity persists until the end of life and does not lead to severe disability, but the other part of the patients is riveted to a wheelchair in the third decade of life.

1. Myopathy of Emery-Dreyfus.

Progresses slowly. The first symptoms appear in children aged 5-15 years. The muscles of the arms and shoulder girdle are affected, contractures in the elbows and hands are gradually formed. At the same time, the muscles of the feet are atrophied, so the child "slaps" with his feet when walking. By a certain age, the process stabilizes. Climbing the stairs remains possible without the use of improvised means. Pseudopergrophy is not characteristic. If the changes in the skeletal musculature are not so pronounced as to chain the child to a wheelchair, then from the heart they are life-threatening. Develops dilated or hypertrophic cardiomyopathy, which disrupts the heart, leads to arrhythmia, blockade, in severe cases, to death. Such patients are installed an artificial pacemaker.

1. Limb-temporal myocardial infarction of Erba-Roth.

It occurs equally often in men and women. The features of the clinical picture include development in 20-30 years, disability occurs after 15 and more years from the time of the onset of the first symptoms. Muscles of the shoulder girdle and pelvic girdle are equally affected. When you look at you, the duck's gait of a man, standing up "by itself "pterygoid" scapula, attracts attention. Pseudohypertrophy is not formed, the facial muscles remain intact. Changes from the heart do not occur.

1. Ophthalmopharyngeal myodystrophy.

It is manifested by the lowering of the upper eyelids (ptosis), popperhivaniem when swallowing (dysphagia) and the appearance of a nasal shade of voice (dysphonia), followed by the addition of weakness in the muscles of the hands, shoulders, legs and pelvic belt.

1. Distal myodystrophy.

They are divided into several types depending on the onset of the disease: with onset in infancy, with onset in childhood, with late debut (type Welander), type of Mioshi, with accumulation of desmine inclusions.

Distal myodystrophies are manifested primarily by the damage to the muscles of the feet and hands. The appearance of spanking feet when walking is noteworthy. Over time, a hollow foot (an increase in the arch of the foot) or pseudohypertrophy of the leg muscles, scoliosis can form. A person is concerned about weakness in the extensor muscles of the hands, which creates difficulties in fine-differentiated hands. Different subtypes of distal myopathies progress with different intensity. In some subtypes, muscle damage spreads higher (hips, lower legs, forearms, shoulders, neck).

Rare forms of progressive muscular dystrophies include skapuloperoneal myodystrophy, Leiden-Moebius pelvic-femoral myodystrophy, Mabry's myodystrophy, and others.

Congenital myodystrophy

Sooner or later, most of the myopathies lead to disability of the patient.

This term denotes myopathies that arose immediately after birth or in the first months of life. Diagnosis of the disease is based on the following criteria:

• Hypotension of muscles (decreased muscle tone) of the child from the first days of life;
• Biopsy confirmation of myopathy;
• Excluded are other diseases with a similar clinical picture.

From the first days of life, the child has generalized weakness of all muscles. Weakness in the diaphragmatic muscles leads to impaired ventilation and infection (the main cause of death), weakness in the muscles of the neck - to inability to hold the head, weakness in the hands and feet - "posture frog ". The child lags far behind in motor development, but the intellect is preserved. Another distinctive feature - contractures in many joints (elbows, ankles, knees). In some children, changes are simultaneously found in the central nervous system (anomalies, demyelination, etc.).

Congenital myodystrophy includes Fukuyama's myopathy, congenital myodystrophy with leukodystrophy and cerebroocular myodystrophy.

The causes and mechanisms of development are not fully known.

Inflammatory myopathies

The causative factor is divided into the following groups:

• Idiopathic myopathies (polymyositis, dermatomyositis). At the heart of the pathology is the defeat of the muscles with the antibodies of the immune system.
• Inflammatory (streptococcal myositis, myositis with influenza, toxoplasmosis, etc.). viral, bacterial or parasitic agents damage the muscles themselves or the products of decay.
• Inflammatory myopathies in the presence of medication.

Inflammatory myopathies proceed with pain syndrome at rest and with the movement of muscles. When examined, muscle soreness, symptoms of intoxication are revealed.

Metabolic myopathies

These diseases are hereditary or acquired nature, which is based on a metabolic disorder in the muscle cells.

Simultaneously with muscle weakness, there are other symptoms of metabolic disorders, endocrine changes.

Diagnostics

Electroneuromyography will help to diagnose muscle weakness.

Diagnostic measures include several areas:

1. Collection of family history (the presence of the disease in relatives).
2. Neurological examination.
3. Laboratory methods.

• Biochemical blood test for CKK (creatine phosphokinase - an enzyme that appears in the breakdown of muscles).
• Blood test for sugar, hormones.

1. Instrumental research.

• ENMG (electroneuromyography).
• Muscle biopsy (one of the reliable diagnostic methods).
• ECG and ECHO-CG (detection of changes from the heart).
• Assessment of LIV (detection of respiratory disorders)
• DNA-diagnostics (genetic examination).

Treatment

The main task in the treatment of patients with hereditary myopathies is to delay the onset of immobility with the rapid formation of contractures and respiratory disorders.

1. Non-drug treatment.

• Exercise therapy.

Passive and active movements in the joints several times a day. Breathing exercises. The intensity of the load depends on the stage of the disease and is gentle-protective mode, so as not to provoke deterioration.

• Massage in a gentle mode.
• Orthopedic correction is aimed at preventing the development of pathological settings in the hands and feet, fighting with contractures with the help of special orthopedic tires, piling for the patient.
• A diet with a high content of protein, vitamins and trace elements.

1. Drug treatment.

The possibilities of drug assistance are significantly limited, since there is no specific treatment. Symptomatic treatment is aimed at maintaining the activity of healthy muscle tissue, reducing contractures and atrophy.

Treatment includes the following groups of drugs:

• B vitamins, vitamins A and E.
• Nonsteroidal anabolics (potassium orotate, ATP).
• Cardiotrophic drugs (riboxin, carnitine chloride).
• Correctors of microcirculation (pentoxifylline).
• Nootropics (piracetam).

1. Surgical treatment is also aimed at combating contractures with ineffectiveness of conservative methods. Produce a dissection of tendons or muscles (achillotomy, myotomy).

Treatment of other myopathies is conducted within the framework of the disease that caused them (treatment of influenza, toxoplasmosis, etc.).

The first medical channel, a neurologist Levitsky G. N. lectures on "Acquired and Metabolic Myopathies

Educational program on neurology, issue on "Myopathy