Myasthenia gravis is an autoimmune neuromuscular disease characterized by a steadily progressing or recurrent course. This serious illness is registered quite often - it affects about 5-10 people out of 100 thousand, with 2/3 of the patients are women. Myasthenia gravis occurs in people aged 15-45 years, but the overwhelming majority of cases are noted in 20-30-year-olds, and occasionally children suffer from it.
In this article, we will consider in more detail the causes of the onset, the mechanism of development and the clinical manifestations (symptoms) of myasthenia gravis. Let's start.
Content
- 1Causes of myasthenia gravis and mechanism of its development
- 2Types of myasthenia gravis
- 3Symptoms of myasthenia gravis
Causes of myasthenia gravis and mechanism of its development
Unfortunately, to date, no one can answer the question "why is myasthenia occurs?" It is believed that a certain role is played by heredity: when a patient is questioned, it is often possible to find out that one of his blood relatives suffers or suffered from this disease.
In a number of cases, myasthenia gravis does not occur independently, but in combination with a tumor of the thymus (thymus gland) or its hyperplasia, or against a background of some systemic diseases of connective tissue (for example, dermatomyositis), cancer (ovarian, breast, lung), or concomitant with amyotrophic lateral sclerosis. If myasthenia gravis develops in combination with the above diseases, it is treated not as an independent pathology, but as a syndrome.
Under the influence of a number of factors (stresses, disturbances in the immunity system, exposure to infectious agents and others) previously healthy organism begins to produce antibodies to its own tissues, namely, to the receptors of the postsynaptic membrane. The main function of the synapse is the transfer of a nerve impulse from one nerve cell (neuron) to another. Under the influence of antibodies, the postsynaptic membrane is gradually destroyed, momentum transfer weakens, and then completely ceases.
When studying the structure of the central system of changes, specific for myasthenia gravis, is not determined. In 30% of cases, the thymus gland is enlarged in size or with the presence of a tumor-like formation. As for the muscles themselves, microscopic examination reveals signs of dystrophy and atrophy of muscle fibers.
Types of myasthenia gravis
Myasthenia gravis can debut in different periods of a person's life and be innate or acquired.
The most common form, as mentioned above, is the acquired myasthenia gravis. This type of pathology can occur both in adolescence and in mature, but most cases occur at a young age of 20-30 years. The disease develops under the influence of a combination of external (in particular, infectious nature) and internal (including genetic) factors. It can flow in different ways: it affects the entire body (generalized form) or mainly the musculature of the eyes (eye form). In the case of severe course of the generalized form of myasthenia gravis, the patient periodically develops a myasthenic crisis, which we will discuss below.
The congenital form of myasthenia gravis, fortunately, is rare enough. In this case, the child falls ill while still in the womb: the disease is transmitted to him from the mother who suffers from myasthenia. In the prenatal period, fetal activity is weak, and immediately after birth, it is determined that the child is very weak, inactive and almost unable to breathe - his muscles are atrophied, including respiratory. In most cases, newborns with congenital myasthenia grains die almost immediately after birth. Sometimes, with timely diagnosis and adequate therapy, the disease recedes.
Symptoms of myasthenia gravis
Muscular weakness in myasthenia gradually progresses and often leads to disability.The basis of clinical manifestations of myasthenia is the syndrome of pathological muscle fatigue. There are 2 forms of myasthenia gravis:
- generalized;
- eye.
When the generalized form affects the musculature of the whole body, with the eye - directly the eye area.
At a certain point in life, a person suffering from a generalized myasthenia gravis, but still not even aware that he is sick, observes a new sensation - a muscle weakness. At first, this weakness occurs only after heavy physical labor, with prolonged movements, especially in the evening. Gradually, muscle weakness progresses and the amount of physical exertion a patient can perform becomes less and less. The striated musculature of the whole body is affected - the neck, trunk, extremities, facial muscles. As a result, the patient feels a widespread weakness in the muscles, and in severe cases, difficulty breathing. Due to the weakness of the sphincters (they are also represented by striated muscles) incontinence of urine and feces develops. In the end, the patient loses the ability to self-service.
The myasthenia glaucoma is characterized by the defeat of the oculomotor muscles: they become weaker, which is manifested by double vision, strabismus, oviposition (ptosis) from one or both sides. In some cases, facial and chewing muscles are involved in the process, as a result of which the patient there are difficulties with eating and expressing emotions on the face (it's hard to frown, smile and so Further). Difficulties also arise with respect to swallowing and speech (noticeable after a long conversation) - the voice acquires a nasal, "gundosy" hue, speech becomes slower, fuzzy.
All the above symptoms of myasthenia gravis are not present all the time, they are dynamic. They are more pronounced after or against a background of general physical activity, while fixing a glance at something, while reading, then there is when the striated muscles of this or that part of the body or this or that organ is maximally tense.
Myasthenia gravis is a chronic disease, steadily progressing. Sometimes it occurs in the form of myasthenic episodes (when basically the disease is in a state of remission, but from time to time there are exacerbations with typical symptoms - as a rule, it is typical for the myasthenia gravis), and sometimes - as a myasthenic state (manifestations of the disease persist for a long time, and remissions are rare and short-term).
In severe form of generalized myasthenia, the patient periodically develops conditions called myasthenic crises. Such a crisis is a sudden onset of severe weakness, localized in the area of the respiratory muscles and pharyngeal muscles. As a result of this weakness, respiratory distress develops: it becomes more frequent, becomes noisy, wheezing; there is a tachycardia (palpitation), drooling. Myasthenic crises carry a direct threat to the life of the patient and require urgent medical attention.
Myasthenia gravis is a formidable disease that, in the absence of treatment, leads to disability of the patient. It is important as soon as possible, with the appearance of the first symptoms of the disease, to seek help from a doctor: he appoint a survey in the required amount and, if the diagnosis is confirmed, treatment. About what methods are diagnosed myasthenia gravis and what are the principles of its treatment, we'll talk in the same article.
The first channel, the program "Live Healthily" with Elena Malysheva on "Myasthenia gravis. How to overcome muscle weakness "
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A training film on "Myasthenia gravis"
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