Myasthenia gravis, the disease Marisa Martín Blázquez suffers from, is an autoimmune and chronic neuromuscular disease characterized by variable degrees of weakness of the body’s (voluntary) skeletal muscles, which increases in times of activity and decreases with rest.
Some muscles, such as those that control eye movement and eyelids, facial expression, chewing, speech, and swallowing, are often affected by this disorder. Those who control breathing and neck, and limb movements may also be affected.
In most cases, this disease affects women under 40 and men over 60 years of age, but childhood and youth myasthenia gravis can also occur. It is not considered hereditary and is not contagious.
Causes of Myasthenia Gravis
It is caused by a defect in the transmission of nerve impulses to muscles in neuromuscular binding. It occurs when the acetylcholine neurotransmitter, which moves in the neuromuscular junction by adhering to its receptors and activating the contraction of the muscle, is blocked or destroyed by antibodies, which prevents muscle contraction from occurring.
According to various research, the thymus gland – an organ of the body under the breastbone that plays an important role in the development of the immune system in the first years of life – is abnormal in adults suffering from myasthenia gravis. This gland may generate incorrect instructions on the production of acetylcholine receptor antibodies.
Symptoms of Myasthenia Gravis
Although it can affect any voluntary muscle, it is most common to affect those who control the movement of the eyes and eyelids, face, and throat. The most common symptoms are as follows:
– Drooping of one eyelid (ptosis)
– Double vision (diplopia)
– Changes in facial expression
– Alterations in speech and voice
– Difficulty chewing and swallowing
– Breathing problems
– Muscle weakness and fatigue
Treatment
With current therapies, most cases of myasthenia gravis do not produce any serious complications. For most individuals suffering from this disease, life expectancy does not decrease, although we must be very attentive if a respiratory crisis occurs and care for it immediately with the right care.
There are several therapies to help reduce muscle weakness. The drugs used to treat this disease are anticholinesterases, which block the degradation of acetylcholine by the enzyme cholinesterase. These drugs help make more acetylcholine available for muscles to work better. Based on the immune mechanism by which the disease occurs, corticosteroids or other immunosuppressants such as methotrexate, azathioprine, or ciclosporin A, alone or associated with corticosteroids, may be used.
Other medicines, including anticholinesterase agents, such as neostigmine and pyridostigmine, are also used, which help improve neuromuscular transmission and increase muscle strength.
Other therapies used are intravenous agents: plasmapheresis, which filters the blood to remove antibodies; intravenous immunoglobulin, which provides normal antibodies; and monoclonal antibodies to alter the immune system. In cases of thymic tumors or thymoma, surgery, a thymectomy, may be considered.