Myasthenia gravis

Myasthenia is an autoimmune disease characterized by weakening of muscles in various localizations. According to its clinical picture, myasthenia gravis affects neurological processes, the immune system and disrupts the functioning of striated muscle tissue. Under the influence of a number of factors, pathological changes occur that affect not only the patient’s health, but also affect appearance and the ability to lead an active lifestyle.

As a rule, myasthenia gravis more often affects middle-aged women. However, there are cases of the disease in children, and there is also an increase in the number of cases in men, mainly after 60 years of age.

Myasthenia gravis is a rather dangerous disease. If it is diagnosed late and not treated properly, there is an extremely high risk of severe complications leading to disability, and the probability of a fatal outcome. Modern technologies allow for accurate diagnosis and subsequent successful treatment of any form of myasthenia gravis (ocular myasthenia gravis, bulbar myasthenia gravis, generalized myasthenia gravis).

Causes of myasthenia gravis

Research and diagnosis of many clinical cases in the field of neurology has shown that the reason why myasthenia gravis develops is a disorder of nerve impulse transmission.

The second cause of the disease is the atypical “behavior” of the thymus gland, causing immune cells to react to proteins in muscle tissue and cause muscle damage and weakness. In addition, myasthenia gravis is a muscle dysfunction disorder triggered by a tumor of the thymus gland. These two diseases often “complement” each other, so not so long ago in P. Hertsen MORI the Center for Pathology of Mediastinum and Myasthenia gravis was created specifically for such patients with immune diseases and cancer.

Other causes of myasthenia gravis include severe stress and immune system malfunctions after viral and infectious diseases. Despite the dynamic nature of the symptoms and the possibility of managing them with drug therapy, myasthenia gravis poses a serious risk.

Classification of myasthenia gravis

Myasthenia gravis is subject to multilevel classification according to several criteria, taking into account a set of signs indicating the stage of the course of the disease.

Myasthenia is classified:

• by the degree of disease progression;
• by the spread of the affecting processes (ocular, bulbar, facial, musculoskeletal myasthenia);
• by the level of decreased motor activity;
• by the degree of compensation of motor system disorders against the background of drug correction.

Myasthenia gravis is expressed in different forms depending on the localization of symptoms:

• ocular myasthenia gravis;
• generalized myasthenia gravis in a mild form with ocular myasthenia gravis symptoms;
• generalized myasthenia gravis in moderate form with symptoms of ocular and bulbar myasthenia gravis;
• severe myasthenia gravis in acute form with pronounced signs of bulbar and respiratory complications;
• severe myasthenia gravis with persistent symptoms and myasthenic crises.

Symptoms of myasthenia gravis

Myasthenia gravis is a chronic disease with exacerbations of the muscular system and neurology.

Early detection of symptoms and causes of the disease allows for effective treatment without the risk of complications.

Myasthenia gravis is accompanied by the following symptoms:

• eyelid drooping (ptosis) – ocular myasthenia gravis;
• symptoms of diplopia (double vision);
• difficulty in swallowing, nasal voice and symptoms of speech defects – bulbar myasthenia gravis;
• general muscle weakness and rapid fatigability – generalized myasthenia gravis;
• symptoms of heart failure;
• neurologic symptoms – distortion of sensitivity to pain and temperature;
• disappearance or reduction in the number of wrinkles;
• signs of a mask-like face;
• distortion of the mouth when trying to smile – the upper lip remains motionless.

At the initial stage of the disease, these symptoms are episodic and are usually relieved after a short rest, with drug therapy, or by cooling the affected area. For example, when diagnosed with ocular myasthenia gravis and severe ptosis, an ice cube applied to the eyelid for a few minutes is sufficient to relieve symptoms.

The factor of temporary symptoms often reduces the patient’s alertness and delays visiting a doctor for diagnosis.

Ocular myasthenia gravis is the primary form in the progression of the disease. The symptoms of ocular myasthenia gravis are always the first to appear and, when worsening, are an obvious sign of disease progression. The sensation of double vision (diplopia) with subsequent worsening, the emergence and progression of weakening of the eyelid muscles are the first symptoms that ocular myasthenia gravis is developing and it is necessary to conduct a diagnosis and identify the cause of these disorders as soon as possible.

Diagnosis of myasthenia gravis

Myasthenia gravis involves diagnosis in several areas at once, regardless of the number and severity of symptoms. To diagnose it correctly and conduct successful treatment, several types of studies are performed to determine the exact cause, form and stage of development of the disease.

• The 1st stage of diagnosis – examination by the attending physician and collection of anamnesis about the current state and development of symptoms;
• a series of tests that reveal disorders of muscle resistance to stress;
• blood tests for autoantibody levels;
• electromyography followed by a test for muscle resistance to stress;
• CT scan of the thymus gland.

The easiest and most accessible way to diagnose myasthenia gravis is by cooling the area being examined, which can reliably diagnose myasthenia gravis and, in particular, ocular myasthenia gravis.

A patient with a suspected diagnosis of “ocular myasthenia gravis” has an ice cube applied to the drooping eyelid for a few minutes. If the eyelid returns to normal after this time, it is considered a clear sign of myasthenia gravis. Differential complex diagnostics, including studies in the field of neurology, immunology and oncology, conducted by specialists at P. Hertsen MORI allows for a reliable diagnosis of “myasthenia gravis”.

Myasthenia gravis treatment

Today, thanks to the well-studied causes of the disease and the development of new highly effective treatment methods, patients diagnosed with myasthenia gravis have a much better chance of being cured and returning to their usual way of life.

Treatment of myasthenia gravis involves both medication and surgery. Taking into account the form of myasthenia gravis and the severity of the disease, the attending physician decides on the appropriateness of one or another method of treatment to achieve the best result.

Since myasthenia gravis is a disease affecting several systems of the body at once, the treatment implies a complex approach, namely normalization of neurological processes and elimination of autoimmune disorders.

Patients diagnosed with myasthenia gravis can be treated both in hospital and in outpatient settings. According to clinical guidelines, myasthenia gravis can be treated in  the following ways:

Surgical treatment of myasthenia gravis:

• Thymectomy;
  After specialized diagnostics, in case of thymus malignancy or progressive course of the disease, the method of choice is surgical treatment with subsequent rehabilitation accompanied by medication correction to stabilize the situation and prevent the development of complications. The minimally invasive method “thoracoscopic thymectomy” is the most effective treatment, allowing to reduce and ease the postoperative period.

Drug therapy and other non-surgical treatment options:

• Treatment with anticholinesterase drugs to relieve symptoms and correct the condition on the neurologic side;
• treatment with diuretics with potassium-saving properties;
• treatment with glucocorticosteroids;
• immunomodulatory therapy;
• plasmapheresis;
• radiation therapy (gamma therapy) on the thymus area.

This type of treatment is used in a number of cases to enhance the effect of thymectomy, as well as in the case when surgery is impossible to be performed.