Myasthenia Gravis is a chronic neurological disease that causes muscle weakness and fatigue. The disease is associated with dysfunction of the immune system, as a result of which it attacks the body's own nerve-muscle interfaces, disrupting the transmission of nerve signals to the muscles. This leads to the inability or significant weakening of muscle contractions.

What is Myasthenia gravis?

Myasthenia gravis is an autoimmune disease that affects the neuromuscular junction, the system that connects nerve cells to muscle cells, allowing them to work together to make muscle movements. Myasthenia gravis causes muscle weakness that usually worsens during the day and improves with rest. The disease usually affects the muscles responsible for eye movements, facial expressions, swallowing and speaking.

Myasthenia gravis is relatively rare, but it can significantly affect the daily life of patients. As an autoimmune disease, myasthenia gravis is classified as a disorder in which the body's immune system mistakenly attacks healthy cells. The prevalence of the disease varies in different parts of the world and depends on many factors, including genetic predisposition and environmental conditions. About 15-20 cases per 100,000 population have been reported in Europe, and it is more common in women than in men.

Myasthenia causes and pathogenesis

Myasthenia gravis is an autoimmune disease, meaning it results from an indiscriminate attack by the immune system on the body's own neuromuscular cells.

The pathogenesis of the disease is based on the incorrect formation of antibodies that try to destroy acetylcholine receptors in the neuromuscular junction. Acetylcholine is an essential substance that ensures the transmission of nerve signals to muscles, allowing them to contract. When antibodies bind to these receptors, they block or even destroy the receptors, resulting in the muscles not receiving sufficient signals and unable to fully contract. This causes muscle weakness and fatigue, which are typical symptoms of myasthenia gravis.

People with myasthenia gravis often experience thymus (chest) enlargement or even tumors, which is thought to be one of the main causes of autoimmune attack. The thymus is an essential part of the immune system that participates in the development of T-cells. Thymic hyperplasia or tumors can create an imbalance in the immune system that promotes the development of an autoimmune response.

Genetic factors can also play a role in the development of myasthenia gravis. Although myasthenia gravis is not usually a directly inherited disease, people with a family history of autoimmune diseases are at greater risk of developing it. Environmental factors, such as various infections or stressful situations, can also be triggers that stimulate the onset of the disease.

What are myasthenia symptoms?

The symptoms of myasthenia gravis can be particularly difficult to predict and can vary in severity from mild bouts of muscle weakness to severe impairment. The course of the disease can be variable, with periods when symptoms worsen (exacerbations) and periods when they decrease (remissions).

The most common symptoms of myasthenia gravis are:

• Muscle weakness: myasthenia mainly affects the muscles that control eye movements, facial expressions, swallowing and speaking. These symptoms usually worsen during the day, especially after prolonged physical activity or prolonged eye focusing.
• Ptoze: another sign is drooping eyelids, or ptosis, which causes drooping of the eyelids and difficulty keeping the eyes open, especially in the evening.
• Double vision: disturbances in nerve signals can cause double vision or diplopia. Patients often report that this symptom worsens when looking at objects for a long time or after intense visual stress.
• Speech and swallowing: muscle weakness can affect the patient's ability to speak clearly and swallow, causing hoarseness, voice changes, and even the risk of choking while eating. This significantly affects the patients' social life and eating habits.
• Muscle fatigue: Symptoms usually worsen during physical activity and improve after rest. Patients may experience rapid muscle fatigue even after light activities such as brushing teeth or talking.

In addition to the classic symptoms, myasthenia gravis can also cause other, less specific manifestations, such as muscle pain or cramps. Signs of autonomic dysfunction, such as reduced sweating or salivation, may also be observed.

Myasthenia diagnosis

Myasthenia gravis can be difficult to diagnose because its symptoms are variable and can mimic those of other neurological diseases. The doctor needs to perform several examinations to confirm the diagnosis and rule out other possible causes.

• Neurological examination: diagnosis includes a neurological examination that assesses the symptoms and extent of muscle weakness. The doctor tests the patient's ability to perform various movements, paying special attention to the muscles of the eyes, face, throat and neck.
• Antibody tests: Blood tests can detect antibodies to acetylcholine receptors or to muscle-specific tyrosine kinase (MuSK), which is an important indicator. About 85% of patients with myasthenia gravis have antibodies against acetylcholine receptors. MuSK antibodies are detected in about 5-10% of patients, and symptoms may be more severe in these patients.
• Edrophini test: this substance may temporarily improve muscle weakness in patients with myasthenia gravis, indicating the presence of the disease. However, this test is less commonly used because of its potential side effects and the need for medical supervision.
• Electromyography (EMG): Electromyography is performed to detect neuromuscular disorders and is one of the most effective tests. EMG is able to detect the reduced transmission of nerve signals to the muscles, which is characteristic of myasthenia gravis.
• CT or MRI scan: imaging of the thymus gland (computed tomography or magnetic resonance imaging) is performed to check the condition of the thymus. Thymus enlargement or the presence of a tumor may be associated with myasthenia gravis.

Myasthenia treatment

• Plasmapheresis and intravenous immunoglobulins (IVIG):

  • Plasmapheresis is the process by which antibodies that attack nerve cells are removed from the blood. It is effective for short-term relief of symptoms, especially in acute cases.
  • IVIG therapy is used to provide the body with healthy antibodies that help reduce the immune system's attack and promote balance in the immune system.
• Removal of the thymus (thymectomy):

  • Removal of the thymus may be an effective treatment for patients with thymic tumor or hyperplasia. This operation can improve the course of the disease and even induce remission in some patients.

For successful treatment and control of myasthenia gravis, consultation with a neurologist or family physician is essential to prevent serious health risks. A quick doctor's consultation can help to start the necessary therapy in time, reducing the risk of progression of complications and improving the general state of health.

What can be myasthenia complications?

Myasthenia gravis can cause several complications, especially if the disease is not properly treated or controlled:

• Respiratory disorders: severe muscle weakness can affect the breathing muscles, causing breathing problems and increasing the risk of pneumonia.
• Swallowing and feeding problems: muscle weakness that affects the swallowing process can create a risk of aspiration (food entering the airways), which can lead to aspiration pneumonia.

If any of the complications of myasthenia appear, it is essential to urgently consult a neurologist or family doctor to prevent serious health risks. A quick doctor's consultation can help to start the necessary therapy in time, reducing the risk of progression of complications and improving the general state of health.

Life with myasthenia gravis

Living with myasthenia gravis can be challenging, but there are a number of ways to improve your daily life and reduce the impact of the disease. It is important to find the right balance between activity and rest, and to get the necessary support from family and medical care.

• Regular check-ups and therapy: by visiting the doctor regularly, it is possible to monitor the progress of the disease and adjust the therapy. Early detection and ongoing monitoring are essential to control symptoms and prevent complications.
• Stress management: stress can worsen the symptoms of the disease, so it is recommended to practice meditation, yoga and other relaxation techniques. Many patients also find relief through art therapy, music therapy, or other creative forms of expression that help reduce anxiety and improve emotional well-being.
• Physical activities: Although physical activity can be tiring, light and controlled activities such as walking, swimming or stretching can improve muscle strength and flexibility. It is important to avoid overexertion, which can worsen symptoms.
• Ergonomic adjustments: ergonomic changes in the daily routine and work environment can significantly reduce the impact of muscle weakness on daily activities. Use assistive devices, such as special chairs, support pillows, or tools that help you perform daily activities with less muscle strain.
• Social support: Sharing experiences and getting support from others dealing with myasthenia can be very important. Support groups and patient associations are a great way to get emotional support and practical advice.

Conclusion

Myasthenia gravis is a chronic disease that requires constant attention and care. With the right therapy, diet, adjustment of physical activities and regular medical examinations, people with myasthenia gravis can live full and active lives. Advances in science and medicine continue to offer new hope for myasthenia gravis patients, making life with myasthenia gravis easier and healthier.

Additional resources

• Information about myasthenia gravis (Source: Miastenija.lv)
• Latvian Association of Neuroimmunologists (Source: Neuroimmunology.lv)