About a month ago my 25-year-old son noticed some tingling in his legs and blurred vision in his left eye. These symptoms have now cleared up completely; but one of his friends, who has multiple sclerosis, told my son that she had similar symptoms at the onset of her illness. We have heard some frightening things about multiple sclerosis and would like to know if we should see a doctor right away.
First, you must not conclude that your son has multiple sclerosis, even though the symptoms he experienced are consistent with early stages of that disorder.
MS is fairly common; it affects about 350,000 Americans, about twice as many women as men. Except for nerve damage due to injury, MS is the most common cause of neurologic disability among young and middle-age adults. The first symptoms of MS occur between the ages 20 and 40 about 90 percent of the time.
MS is called a "demyelinating" disorder because it results from destruction of myelin sheaths that surround nerve cells in the brain and spinal cord. The damage to myelin is thought to be due to an autoimmune process, in which an unexplained immune reaction attacks and destroys body tissues instead of protecting them. The damage, referred to as "plaques," can be detected by magnetic resonance imaging even where there are only mild symptoms.
The initial symptoms of MS may be quite subtle. They include weakness or unusual sensations in one or more extremities; blurring or loss of vision, most often in one eye and associated with pain around the eye; double vision; and dizziness. Later in the course of the disease, people may develop clumsy gait, memory loss and speech difficulties.
The entire course of MS follows one of three general patterns: relapsing-remitting, progressive or benign. About 80 percent of patients have the relapsing-remitting form, characterized by multiple symptomatic episodes followed by total or partial recovery. Over a period of years of this pattern, patients may gradually have more and more persistent neurological changes.
In 30 percent of these patients, the disease becomes steadily progressive after about 10 years. The progressive form follows a steady pattern of worsening symptoms and disability without periods of remission. About 10 percent of MS patients have a benign course with relatively minor manifestations.
Despite this generally gloomy picture of MS, there is some good news to report. As long as 25 years after the initial diagnosis, 25 percent of patients are still able to work, 5 percent to 10 percent have little or no disability, and life expectancy is close to normal.
In addition, some promising new treatments are now available. For many years the only treatment for MS was adrenal corticosteroids, which may lessen the symptoms and duration of the relapses but do not alter the long-term manifestations of the disorder.
Over the past three years the Food and Drug Administration has approved two drugs, interferon beta- 1b (Betaseron) and interferon beta- 1a (Avonex) for treating the relapsing-remitting form of MS. Both are naturally occurring substances which regulate the immune system.
Both have been shown to reduce the rate of relapses by more than a third and diminish their severity.
Approved recently by the FDA was a third drug, copolymer 1 or Copaxone, which is a synthetic chain of four amino acids. In clinical trials, this product has shown benefits similar to the two interferons.
You can get more information on MS from the National Multiple Sclerosis Society by calling (800) FIGHT-MS ( 344-4867).
Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine.
Pub Date: 12/31/96