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Additional Information
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What is Multiple Sclerosis?
An
unpredictable disease of the central nervous system, multiple
sclerosis (MS) can range from relatively benign to somewhat
disabling to devastating, as communication between the brain
and other parts of the body is disrupted. Many investigators
believe MS to be an autoimmune disease -- one in which the
body, through its immune system, launches a defensive attack
against its own tissues. In the case of MS, it is the nerve-insulating
myelin that comes under assault. Such assaults may be linked
to an unknown environmental trigger, perhaps a virus.
Most
people experience their first symptoms of MS between the
ages of 20 and 40; the initial symptom of MS is often blurred
or double vision, red-green color distortion, or even blindness
in one eye. Most MS patients experience muscle weakness
in their extremities and difficulty with coordination and
balance. These symptoms may be severe enough to impair
walking or even standing. In the worst cases, MS can produce
partial or complete paralysis. Most people with MS
also exhibit paresthesias, transitory abnormal sensory feelings
such as numbness, prickling, or "pins and needles" sensations. Some
may also experience pain. Speech impediments, tremors,
and dizziness are other frequent complaints. Occasionally,
people with MS have hearing loss. Approximately half of all
people with MS experience cognitive impairments such as difficulties
with concentration, attention, memory, and poor judgment,
but such symptoms are usually mild and are frequently overlooked. Depression
is another common feature of MS.
Is
there any treatment?
There is as yet no cure for MS. Many patients do well with no therapy at all, especially since many medications have serious side effects and some carry significant risks. However, three forms of beta interferon (Avonex, Betaseron, and Rebif) have now been approved by the Food and Drug Administration for treatment of relapsing-remitting MS. Beta interferon has been shown to reduce the number of exacerbations and may slow the progression of physical disability. When attacks do occur, they tend to be shorter and less severe. The FDA also has approved a synthetic form of myelin basic protein, called copolymer I (Copaxone), for the treatment of relapsing-remitting MS. Copolymer I has few side effects, and studies indicate that the agent can reduce the relapse rate by almost one third. An immunosuppressant treatment, Novantrone (mitoxantrone), is approved by the FDA for the treatment of advanced or chronic MS.
One monoclonal antibody, natalizumab (Tysabri), was shown in clinical trials to significantly reduce the frequency of attacks in people with relapsing forms of MS and was approved for marketing by the U.S. Food and Drug Administration (FDA) in 2004. However, in 2005 the drug’s manufacturer voluntarily suspended marketing of the drug after several reports of significant adverse events. In 2006, the FDA again approved sale of the drug for MS but under strict treatment guidelines involving infusion centers where patients can be monitored by specially trained physicians.
While steroids do not affect the course of MS over time, they can reduce the duration and severity of attacks in some patients. Spasticity, which can occur either as a sustained stiffness caused by increased muscle tone or as spasms that come and go, is usually treated with muscle relaxants and tranquilizers such as baclofen, tizanidine, diazepam, clonazepam, and dantrolene. Physical therapy and exercise can help preserve remaining function, and patients may find that various aids -- such as foot braces, canes, and walkers -- can help them remain independent and mobile. Avoiding excessive activity and avoiding heat are probably the most important measures patients can take to counter physiological fatigue. If psychological symptoms of fatigue such as depression or apathy are evident, antidepressant medications may help. Other drugs that may reduce fatigue in some, but not all, patients include amantadine (Symmetrel), pemoline (Cylert), and the still-experimental drug aminopyridine. Although improvement of optic symptoms usually occurs even without treatment, a short course of treatment with intravenous methylprednisolone (Solu-Medrol) followed by treatment with oral steroids is sometimes used.
What
is the prognosis?
A physician may diagnose
MS in some patients soon after the onset of the illness.
In others, however, doctors may not be able to readily
identify the cause of the symptoms, leading to years
of uncertainty and multiple diagnoses punctuated by baffling
symptoms that mysteriously wax and wane. The vast
majority of patients are mildly affected, but in the
worst cases, MS can render a person unable to write,
speak, or walk. MS is a disease with a natural
tendency to remit spontaneously, for which there is no
universally effective treatment.
To read the rest of this article from the National Institute
of Neurological Disorders and Stroke (NINDS), please click
here: http://www.ninds.nih.gov/disorders/multiple_sclerosis/multiple_sclerosis.htm
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