Myasthenia gravis - Causes, Symptoms and Treatment .MF .

August 12, 2017 17:52 | Nerve Disease

Myasthenia - a chronic, progressive disease with the presence of crises characterized by abnormal fatigue and muscle weakness.

first described back in 1672 by Thomas Willis.Currently, the incidence of myasthenia growing 5 - 10 patients per 100 000 population.

Causes Myasthenia gravis

- it is a genetic disease, but at the genetic level is not sufficiently studied.It attaches great importance to the gene mutation responsible for the nervous - muscular synapses.We found two of the disease mechanism:

  • biochemical changes in the synapses mionevralnyh of a change in function of the hypothalamus with secondary involvement in the process of thymus (thymus);
  • autoimmune damage of the thymus with impaired neuromuscular transmission.This reduces the synthesis of acetylcholine and cholinesterase activity increases.

triggering factor may be stress, colds, impaired immune functions of the body, leading to the formation of antibodies against its own cells against acetylcholine receptors of the postsynaptic m

embrane of nerve - muscle connections (synapses).Normally, these synapses transmit the impulse from the nerve to the muscle by means of biochemical reactions involving the neurotransmitter acetylcholine.

When excited by acetylcholine acts through presynaptic membrane into the synaptic cleft in the cholinergic receptors of the postsynaptic membrane (muscle), causing her arousal.The enzyme acetylcholinesterase breaks down the neurotransmitter limiting its duration.In myasthenia this complex mechanism is broken.At the ends of synaptic acetylcholine produced little or it is destroyed cholinesterase hard and result in the synapse and blocked nerve impulse becomes impossible.

myasthenia gravis usually starts in the 20 - 40 years.More common in women than men (2: 1).

symptoms of myasthenia

main feature of myasthenia gravis - weakness and fatigue dramatically skeletal muscles when working or her long-term stress.Muscle weakness increases during repeated movements, especially at a rapid pace.Muscle, as it were "tired" and stop listening until the complete paralysis.After resting muscle function is restored.In the morning, after sleeping, the patient feels generally normal.A few hours of wakefulness leads to increased myasthenic symptoms.

There are three forms of myasthenia gravis:

  • eye;
  • bulbar;
  • generalized.

first often affects the muscles, which are innervated by cranial - cerebral nerves.Subsequently neck muscles may result in a lesser degree torso muscles and limbs.The first signs of the disease is the drooping of the upper eyelid and double vision, which occur at a lesion of external muscles of the eyeball, the circular muscles of the eyes, muscles, lifting the upper eyelid.If in the morning the patient can open his eyes fully and freely, then further blinking leads to weakening of the muscles of the eyelid and just "hanging".This eye shape.

Pictured ptosis in myasthenia

When bulbar form affects the muscles innervated by bulbar group of nerves.At the same time there will be a violation of swallowing, chewing.It will change - will be quiet, hoarse, nasal, hoarse voice would quickly dwindle down to a silent speech.

In the most common, generalized form, the process begins with the eye muscles, and then all the muscles involved in it.The first to suffer from neck muscles and facial muscles.The patient has difficulty in retaining the head.There is a peculiar expression on his face with a transverse smile and deep wrinkles on the forehead.It appears drooling.Later joined by weakness of muscles.The patient goes bad, can not serve themselves.Condition better in the morning, the evening deteriorated.Each subsequent movement of the patient becomes more difficult to perform.Over time, the muscles atrophy.The most affected proximal parts - shoulders, hips.
tendon reflexes were quickly exhausted and appear after the rest.

Pictured Generalized form of myasthenia

survey myasthenia

electromyography for the diagnosis of a value, which detects the myasthenic reaction pharmacological test - a significant improvement after the administration of anticholinesterase drugs (Neostigmine 1 ml of 0.05% / m)and immunological test - determination of antibody titer to the acetylcholine receptors, and the discovery of a thymoma (a tumor of the thymus gland) - computed tomography of the anterior mediastinum.

myasthenic crisis

flow myasthenia progressing with the increase of symptoms and its severity.In severe in patients having myasthenic crises.

myasthenic crisis - a sudden onset of severe weakness of the respiratory and pharyngeal muscles - respiratory failure (frequent wheezing), increased heart rate, salivation.Paralysis of the respiratory muscles during severe crisis - a direct threat to the patient's life.

Myasthenia gravis is a chronic serious illness, progressive, often resulting in disability and requires careful observation and treatment.

patients with myasthenia.

myasthenic syndrome may occur with lethargic encephalitis, bronchogenic carcinomas (tumors) lung (Lambert Syndrome - Eaton), amiotrotroficheskom lateral sclerosis, thyrotoxicosis.There are a number of congenital myasthenic syndromes which are based on mutations in the genes of different subunits of the acetylcholine receptor.

treatment of myasthenia

essential drugs in infants are anticholinesterase drugs - kalimin, Neostigmine.Assigned dosage and time of administration is necessary to strictly observe because of the risk of overdose and the development of cholinergic intoxication - cholinergic crisis - convulsions, twitching, slow heart rate, contraction of the pupils, salivation, pain, abdominal cramps.The antidote to this is atropine overdose n / a or / in the 0.5 - 1.0 ml.

Treatment anticholinesterase drugs is carried out over the years, adjusting medications, depending on the severity of the disease: oksazil, Neostigmine, kalimin, galantamine.To reinforce their actions used potassium salts, for the delay of potassium in the body is used spironolactone courses.In severe use hormone therapy and cytostatics.

effectively "pulsterapiya" - large doses of hormones (1000 - 2000 mg of prednisolone) with dalneyim tapering.Immunosuppressants - azotioprin, cyclosporine, cyclophosphamide.When a thymoma operative treatment.

In severe cases of myasthenic crisis held in intensive care units mechanical ventilation, plasmapheresis, immunoglobulin administration, Neostigmine in / ephedrine n / a.

Special Diet is not required, but it is advisable to eat foods rich in potassium: apricots, raisins, potatoes.

If found myasthenia

main institution for the study, diagnosis and treatment of myasthenia gravis and myasthenic syndromes is myasthenic Moscow Center, based at the department of neuro - muscular pathology Institute of General Pathology and Pathophysiology, Russian Academy of Medical Sciences in 1983.In Russian medicine for the treatment of myasthenia gravis are included in the federal list and grace dispensed by prescription free: metipred, prednisolone, kalimin, neuromidin, veroshpiron, cyclophosphamide, azotioprin.

Patients with myasthenia gravis should be observed at the neurologist who regularly take prescribed treatment and follow all recommendations.Under such conditions the possible long-term preservation and quality of life disability.

patients with myasthenia can not sunbathe, hard physical work, use of magnesium preparations, muscle relaxants, antipsychotics and tranquilizers, diuretics (except veroshpirona), aminoglycosides (gentamicin, kanamycin, neomycin, streptomycin, ...), ftorhinoliny (norfloxacin, ofloxacin), tetracycline derivatives of quinine, D-penicillamine.All patients were given a list of a physician and it should always be with me, not to take the drug is invalid.

can not engage in self-treatment, herbal medicine.Patients with myasthenia no medicine should not be given without first talking to your doctor!Curariform substances increase myasthenic phenomenon.

Sanatorium and resort treatment in the hot season in the south is not shown.Recommended sanatorium - resort treatment in spas with medical profile: treatment of nervous diseases (brain disease);sanatorium "Alatyr" (Mordovia), "d'Angers" (Kemerovo region), "Bakirovo" (Tatarstan), "Arshan" (Republic of Buryatia), "Barnaul" (Altai Territory), "Beshtau" and "Dawn of Stavropol '(Stavropolregion) "," Golden ear ", resort complex" Knowledge "(Krasnodar region), the name of the sanatorium Borodin (Kostroma region)," Emerald "(Primorye), Moscow sanatorium and Saint - Petersburg and many other resorts in Russia and the. CIS

doctor's consultation on myasthenia

question: is it possible to fully recover from myasthenia
Answer: no, but as a result the proper and long-term treatment can achieve the complete disappearance of the symptoms and long-term remission

Question. whethermyasthenic crisis be caused by improper treatment
Answer: can Inadequate dose anticholinergic drugs are ineffective and may develop myasthenic crisis Overdose their lead to cholinergic crisis...Both crisis requires immediate hospitalization, possibly in the intensive care unit of the - of the threat of respiratory arrest.

Question: Is it possible to sunbathe during prolonged remission?
The answer is no.Sun exposure can cause an aggravation of myasthenia, even with long-term remission.

Question: Does myasthenia hereditary?
The answer is no.

Question: Does a normal pregnancy and birth possible?
answer possible.Pregnancy should be planned, consult a doctor.Admission cytostatics is contraindicated for pregnant women and better solve the problem of translation into other drugs in advance.Everything is decided individually.Inherited myasthenia gravis is not transmitted.

neurologist Kobzev SV