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Time is starting to show its ugly head.
Myasthenia Gravis (MG) Myasthenia Gravis comes from the Greek and Latin words meaning grave muscular weakness. The most common form of MG is a chronic autoimmune neuromuscular disorder that is characterized by fluctuating weakness of the voluntary muscle groups. Clinical Features & Symptoms MG occurs in all races, both sexes and at any age. MG is not directly inherited nor is it contagious. MG may affect any muscle that is under voluntary control. Certain muscles are more frequently involved and these include the ones that control eye movements, eyelids, chewing, swallowing, coughing and facial expression. Muscles that control breathing and movements of the arms and legs may also be affected. Weakness of the muscles needed for breathing may cause shortness of breath, difficulty taking a deep breath and coughing. Other muscles that may be affected include those of the back, neck and limbs. Although MG is said to be painless, pain in the back, neck and head may be present if neck muscles which hold up the head are weak and in spasm. Shoulder weakness is demonstrated by trouble holding up an arm to comb or shampoo one's hair, or to shave or put on makeup. The grip may become weak opening jars (and childproof medicine bottles), hips may be weak getting out of deep chairs or the bathtub, and legs may tire climbing stairs or when walking distances. The muscle weakness of MG increases with continued activity and improves after periods of rest. MG involves many of the voluntary muscles of the body including those needed for breathing. When the weakness is severe and involves breathing, hospitalization is usually necessary. The typical untreated patient may feel strong on awakening from a night's rest or a nap, but experiences increasing muscle fatigue as the day progresses. Although MG can be fatal if a respiratory crisis is not immediately treated, normal life expectancy is the rule with proper treatment. Treatment There is no known cure for MG, but there are effective treatments that allow many, but not all people with MG, to lead full lives. Common treatments include medications, thymectomy and plasmapheresis. Spontaneous improvement, even remission, may occur without specific therapy. Medicines don't do anything to cure MG, but they can provide a temporary crutch to help patients function better. Some muscles may improve for a few hours while others may be unresponsive or even get weaker on these medications. The medication produces its maximal effects (good and bad) about one to two hours after ingestion, and these effects wear off after about three hours or sometimes longer. These medicines can cause stomach cramps and gut hyperactivity, Increased perspiration, salivation, muscle twitching and muscle cramps are other unpleasant side effects sometimes experienced with this type of medication. A lot of common-sense things can be very effective in coping with MG. Plenty of rest and a well-balanced diet actually help reverse the weakness. Preference should be given to foods high in potassium, such as oranges, tomatoes, apricots and their juices, bananas, broccoli and white meat of fowl. If possible, one should try to avoid exposure to infections and all forms of stress, but of course that's easier said than done. It is very important that patients try to pace their activities so that they don't fatigue themselves unnecessarily. This may mean resting the eyes by closing them for a few minutes each hour or lying down briefly several times during the day. Avoid Exacerbation, many things can exacerbate myasthenic weakness temporarily, including infections (such as a cold, pneumonia, or even a tooth abscess), fever, excessive heat or cold, over-exertion, and emotional stress. Prognosis The current treatments for MG are sufficiently effective that the outlook for most patients is bright. Although the treatments will not cure MG, most patients will have significant improvement in their muscle weakness. In some cases, MG may go into remission for a time period when no treatment is necessary. There is much that can be done but still much to understand. New drugs to improve treatments are needed. Research plays an important role in finding new answers and treatments for MG. What Causes Autoimmune MG? The voluntary muscles of the entire body are controlled by nerve impulses that arise in the brain. These nerve impulses travel down the nerves to the place where the nerves meet the muscle fibers; this space is called the neuromuscular junction. When the nerve impulse originating in the brain arrives at the nerve ending, it releases a chemical called acetylcholine which travels to the muscle fiber side of the neuromuscular junction where it attaches to many receptor sites. The muscle contracts when enough of the receptor sites have been activated by the acetylcholine. In MG, there is as much as an 80% reduction in the number of these receptor sites. The reduction in the number of receptor sites is caused by an antibody that destroys or blocks the receptor site. The antibodies destroy the receptor sites more rapidly than the body can replace them. Muscle weakness occurs when acetylcholine cannot activate enough receptor sites at the neuromuscular junction.
Primary Lateral Sclerosis It is a degenerative upper motor neuron disease under the "MND Diseases umbrella", like ALS, it does have some lower motor neuron problem signals that can be detected on an EMG test, but it does not mean that it will change to ALS. If the findings show lower motor neuron involvement, it does not make a diagnosis of ALS, it is a combination of these and upper motor neuron findings. PLS strikes the voluntary muscles, and usually begins in the legs. Initial symptoms may include difficulty with balance, weakness and stiffness in the legs, muscle spasms, and dragging the toes while walking. Occasionally PLS may begin in the tongue or hands. In the tongue, the initial symptom is slurring of words. In the hands symptoms include weakness and stiffness in the fingers, general clumsiness, and fatigue doing repetitive tasks with the fingers. PLS is life-style threatening, not life threatening. It is not fatal. Dysfunction and disability accrue as PLS progresses. In most cases, due to its slow course over approximately 20 years, PLS does not clearly shorten patients' lives. This may not be true for patients who are young when PLS presents, who would have a life expectancy (without PLS) of more than 20 years, on the average. Primary lateral sclerosis (PLS) is a progressive, degenerative disease of upper motor neurons characterized by progressive spasticity (stiffness), which affects the lower extremities, trunk, upper extremities and bulbar muscles (usually in that order). The process that is initially considered PLS has the potential to be reclassified as ALS if sufficient signs of both upper and lower motor neuron involvement develop over time. In some cases, such reclassification may only occur at autopsy Patients with PLS may occasionally have mild, nonspecific and non-progressive findings of de-nervation on electrodiagnostic testing. These patients may be concerned that their PLS could eventually evolve into ALS. Although absolute guarantees cannot be given, it is reasonable to derive some measure of reassurance from the overall slow progression in these patients. PLS progresses at a much slower rate than ALS. Therefore, patients with PLS may expect to live longer. Issues of progressive disability are shared by all patients with all forms of MNDs, regardless of type. Disability is usually commensurate with the clinical progression, and will develop at a slower rate in patients with PLS, compared to ALS. The specific disabilities may differ between the two diseases. Frequency of PLS is uncertain. In contrast, ALS affects between 2-3 new patients per 100,000 population, each year. An annual PLS incidence rate of 1 per 10 million (0.01 per 100,000 per year), which is approximately |
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