Myasthenia gravis is a chronic and debilitating disease and is characterized by weakness and fatigue of any muscle under voluntary control. This means that muscles which are involuntary, such as the heart muscle or those which control the intestinal tract, are not affected. Muscles which individuals have control over such as the eyes, legs, arms and trunk are affected by a breakdown in the normal communication between nerves and muscle.
Currently there is no known cure for myasthenia gravis, but there are treatments that can help relieve the symptoms which sufferers experience on a daily basis. This condition can affect people of any age, but it is more common in women younger than 40 and in men older than 60. There are two different types of myasthenia gravis. In the first case there is an immune mediated response which occurs in adults and in the second case the condition is the result of a genetic problem and children are primarily affected.
Initially, individuals who suffer from myasthenia gravis may find difficulty with speaking or swallowing. But more often individuals will first notice problems with drooping eyelids or double vision. Individuals can also have nasal sounding speech as a result of weak muscles that control the vocal cords. Symptoms can also include a weak neck muscles that give individuals a tendency to fall forwards or backwards.
These types of symptoms will occur in approximately 90 percent of the cases and are usually intermittent. This means that the symptoms will come and go. They can disappear for weeks at a time and then recur. This muscle weakness will worsen as the affected muscle is used repeatedly. This means that after climbing the stairs once or twice leg muscles may feel weak or after doing several situps stomach muscles may fatigue easily.
In more than half the people who develop myasthenia gravis the first symptoms are eye problems which include drooping of one or both eyelids, double vision or blurred vision. In approximately 15 percent of people, the first symptoms involve face and throat muscles which affects speech, swallowing, chewing and facial expressions.
Family members may notice that you don’t smile as often if the muscles that control your facial expressions are affected. The weakness in the arms and legs usually happen in conjunction with weakness in the other parts of the body such as the eyes base or throat. The disorder usually affects the arms more than the legs, but when the legs are affected it wil change your gait and the way you walk.
Because symptoms will improve with rest, the muscle weakness can come and go. Generalized weakness often develops in the trunk, arms and legs within a year of the initial symptoms. It appears that arm muscles are usually most affected and muscle weakness will worsen as the day progresses. Interestingly, pregnancy will have a variety of responses on myasthenia gravis. Individuals can either improve, worsen or will have little effect on the current disease process. In some women symptoms will first occur during pregnancy or after delivery.
Individuals may complain of symptoms as a result of the muscle weakness that include frequent gagging or choking, functioning best after having rested or first thing in the morning, difficulty climbing stairs or lifting objects, needing to use their hands to rise from the sitting position, difficulty maintaining a steady gaze, hoarseness or changing voice quality, drooling or even breathing difficulties.
Myasthenia gravis does not cause true tremors but individuals with arm weakness may have a sensation of tremor when attempting to perform an activity. The weakness of the muscle can make difficulty with movement feel uncoordinated. Myasthenia gravis also does not cause seizure activity, cramping or weakness only on one side of the body.
After diagnosis individuals should be apprised of the condition called myasthenia gravis crisis. During a crisis time the condition affects muscles which control breathing resulting in a shortness of breath. During a crisis the individual will will be unable to breathe to the point that they need a ventilator or a breathing machine. Although the term crisis is used to describe this condition it usually happens over several days to weeks and not suddenly. This type of myasthenia gravis crisis is often the result of another medical condition such as infection which stresses the body.
Although there is no cure for myasthenia gravis there are treatment protocols which enable patients to live productive and full lives. It is important to communicate with your physician about any side effects you may experience from medications that you may be taking or communicate any other symptoms that you may experience. Only through open communication with your practitioner will you and he be able to most appropriately and effectively treat your condition.
MayoClinic: Myasthenia Gravis
Autralian Myasthenic Association: The Symptoms of Myasthenia Gravis
National Institute of Neurological Disorders and stroke: Myasthenia Gravis Fact Sheet
Boston Children’s Hospital: Myasthenia Gravis
Johns Hopkins Medicine: Myasthenia Gravis