Definition of Amyotrophic lateral sclerosis (ALS)
Amyotrophic lateral sclerosis (ALS): A classic motor neuron disease. Motor neuron diseases are progressive chronic diseases of the nerves that come from the spinal cord responsible for supplying electrical stimulation to the muscles. This stimulation is necessary for the movement of body parts.
LOU GEHRIG'S DISEASE: Amyotrophic lateral sclerosis is quite a mouthful. The disease is therefore usually referred to simply as ALS. In North America it is sometimes called "Lou Gehrig's disease" after the great durable baseball player who had it. The movie, "Pride of the Yankees", tells the his life story. As a New York Yankee, Gehrig was named the American League's most valuable player 4 times (in 1927, 1931, 1934 and 1936). In 14 seasons Gehrig did not miss a single game for a total of 2,130 games. Gehrig was born in 1903, and he died in 1941 at the age of 38.
EPIDEMIOLOGY: ALS strikes in mid-life, most often in the fifth through seventh decades of life. Men are about one-and-a-half times more likely to have the disease as women. It affects about 20,000 Americans with 5,000 new cases occurring in the United States each year.
THE DISEASE PROCESS: ALS occurs when specific nerve cells in the brain and spinal cord that control voluntary movement gradually degenerate. The loss of these motor neurons causes the muscles under their control to weaken and waste away, leading to paralysis. The cause of this disease process is still unknown.
SIGNS AND SYMPTOMS: ALS manifests itself in different ways, depending on which muscles weaken first. Symptoms may include tripping and falling, loss of motor control in hands and arms, difficulty speaking, swallowing and/or breathing, persistent fatigue, and twitching and cramping, sometimes quite severely.
TREATMENT: There is no cure for ALS; nor is there a proven therapy that will prevent or reverse the course of the disorder. The Food and Drug Administration (FDA) approved riluzole, the first drug that has been shown to prolong the survival of ALS patients. Patients may also receive supportive treatments that address some of their symptoms.
PROGNOSIS (OUTLOOK): ALS is progressive and fatal. The usual causes of death of patients with motor neuron diseases are not directly related to the disease, but result from simultaneous additional illnesses which ultimately occur because of weakness of the body. These illnesses are often infections.
DURATION OF DISEASE: ALS usually leads to death within 5 years of the time the diagnosis of ALS is made; the range is from 2 to 7 years.Source: MedTerms™ Medical Dictionary
Last Editorial Review: 6/14/2012
Medical Dictionary Definitions A - Z
Search Medical Dictionary