Causes of myasthenia gravis
Due to the acute reaction of our own immune system, antibodies are formed that act against our own acetylcholine receptors, which interferes with the transmission of impulses from motor nerve endings to the muscles. This results in muscle weakness and excessive tiredness. The cause of myasthenia gravis isn’t fully known, but in about 60% of patients the antibodies associated with the disease are produced in the thymus gland – an organ that dissapears in a healthy adult.
Symptoms of myasthenia gravis
The most characteristic symptom of myasthenia gravis is excessively rapid tiredness of muscles that subsides after rest. Myasthenia gravis attacks various muscle areas, usually the muscles of the eyelids and moving the eyeballs causing drooping eyelids, and/or double vision.
Often facial muscles, muscles involved in chewing and swallowing, and muscles of the arms and legs. Symptoms of tiredness seem to be stronger in the evening than in the morning.
Diagnosis and treatment
To diagnose myasthenia gravis, you should see a neurologist who will take a history and perform tests for muscle strength and tiredness. Tests to confirm myasthenia gravis include electromyography (EMG), a blood test for acetylcholine receptor antibodies and a CT scan to examine the presence and condition of the thymus gland.
Myasthenia gravis is a chronic disease whose symptoms can be controlled, but without the effect of a cure. The course of the disease is variable depending on various factors such as hormonal changes, stress or infection.
The main treatments for myasthenia gravis include orally administered acetylcholinesterase inhibitors, i.e. pyridostigmine and ambenonium. If this type of treatment isn’t sufficient, immunosuppressive drugs (corticosteroids, azathioprine, cyclophosphamide or methotrexate) that act on the immune system are introduced.
In people whose disease is associated with thymic abnormalities, thymectomy – surgery to excise this organ – is used. It’s also extremely important to treat comorbidities, control drug dosage and rest. Despite the many ways that cause myasthenia gravis symptoms to be reduced to a minimum, other active substances and treatments that improve the quality of life of patients are still being sought. Currently, an interesting method at the level of clinical trials for the treatment of myasthenia gravis is the use of cladribine.