Myasthenia gravis: what it is, symptoms and treatment

Myasthenia gravis, or myasthenia gravis , is an autoimmune disease that causes progressive muscle weakness. It is more common in women and usually begins between 20 and 40 years of age. Symptoms of myasthenia gravis may start suddenly, but they usually start to appear and gradually get worse.

The causes of myasthenia gravis are related to a change in the immune system that causes antibodies to attack certain structural structures that are essential for muscle control.

Myasthenia gravis does not have a permanent cure, but the treatment adapted to each case with specific remedies and physical therapy exercises can improve the quality of life.

Possible symptoms

The most common initial symptoms of myasthenia gravis are:

• Eyelid weakness and difficulty in opening the eyes or blinking; Weakness of the eye muscles, which leads to strabismus and double vision; Excessive muscle tiredness after exercise or physical effort.

As the disease progresses, symptoms worsen and include:

• Weakness of the neck muscles that leave the head hanging forward or to the side; Difficulty climbing stairs, raising arms, writing; Difficulty speaking and swallowing food; Weakness of arms and legs, which varies in intensity throughout hours or days.

In the most severe episodes, there may also be impairment of the respiratory muscles, a condition called myasthenic crisis, which is serious and can lead to death if it is not treated quickly in the hospital.

Symptoms usually worsen with repetitive use of the affected muscle, but it can also happen when you are exposed to heat, when you are under stress or anxiety, or when using anxiolytic drugs or antibiotics.

How the diagnosis is made

Most of the times the doctor is suspicious of the diagnosis of myasthenia gravis through the assessment of symptoms, physical examination and the study of the person's health history.

However, several tests can be used to screen for other problems and confirm myasthenia gravis. Some of these tests include electromyography, MRI, computed tomography and blood tests.

What causes myasthenia gravis

Myasthenia gravis is caused by a change in the immune system that causes some antibodies to attack receptors in muscles. When this happens, the electrical message is unable to pass correctly from neurons to muscle fibers and, therefore, the muscle does not contract, demonstrating the characteristic weakness of myasthenia.

How the treatment is done

There are several types of treatment that can improve a person's quality of life, depending on the symptoms presented. Some of the most used forms include:

1. Remedies

Medicines are the most used form of treatment because, in addition to being practical, they have excellent results. The most used types of drugs are:

• Cholinesterase inhibitors, such as Pyridostigmine: improve the passage of the electrical stimulus between the neuron and the muscle, improving muscle contraction and strength; Corticosteroids, like Prednisone: decrease the effect of the immune system and, therefore, can reduce various types of symptoms. However, they cannot be used for a long time, as they can have several side effects; Immunosuppressants, such as Azathioprine or Ciclosporin: these drugs also reduce the functioning of the immune system, but are used in more severe cases, when symptoms do not improve with other drugs.

In addition to oral remedies, the doctor may also recommend the use of intravenous medication, such as monoclonal antibodies, which decrease the amount of some defense cells in the body, improving the symptoms of myasthenia gravis .

2. Plasmapheresis

Plasmapheresis is a therapy, similar to dialysis, in which blood is taken from the body and passed through a machine that removes excess antibodies that attack muscle receptors, facilitating the passage of the electrical signal between neurons and muscle fibers.

Although it is a treatment with good results, it also has some health risks such as bleeding, muscle spasms and even severe allergic reactions.

3. Surgery

Surgery is a rarer treatment, but it may be necessary when a tumor is identified in an organ of the immune system that is causing the production of antibodies that generate myasthenia gravis.

4. Physiotherapy

Motor and respiratory physiotherapy are also indicated for the treatment of myasthenia gravis in order to strengthen the muscles, improve the range of motion, breathing and prevent respiratory infections.