Amyotrophic Lateral Sclerosis
Also known as: Lou Gehrig's disease
What is it?
Amyotrophic lateral sclerosis (ALS) is a progressive
disease in which the nerve cells that control voluntary
muscle movement gradually deteriorate, leading to muscle
weakness and eventual paralysis. “Amyotrophic” means the
loss of muscle bulk, “lateral” refers to the nerve tracks
running down both sides of the spinal cord that are
affected, and “sclerosis” refers to the thickening or
hardening of the muscle tissue. Also called Lou Gehrig's
disease, after the celebrated American baseball player who
died of ALS. ALS is also referred to as a motor neuron
disease.
Who gets it?
ALS is a rare disease, affecting approximately 30,000
Americans. It is usually diagnosed in people between the
ages of 35 and 70. It is slightly more common in men than
women.
What causes it?
The cause of ALS is not known. While it can run in
families, called familial ALS, it is most often found in
people with no family history of the disease, called
sporadic ALS. There is a possibility that there is a
connection between sporadic ALS and an overproduction of
toxic molecular fragments called free radicals in the
body, an autoimmune response, viral factors, environmental
toxins, or premature aging. However, research has not been
conclusive. Western Pacific ALS is a form of the disease
that is seen in Guam and other Pacific islands. This form
of ALS includes some symptoms of Parkinson's disease.
What are the symptoms?
The symptoms of ALS occur when the motor neurons in the
brain and spinal cord begin to degenerate. The motor
neurons are nerve cells responsible for sending messages
from the brain to the muscles to stimulate movement. As
the motor neurons degenerate and die, the muscles become
weak and incapable of normal movement, which leads to a
loss of muscle bulk, called wasting. The weakness usually
begins in the hands, making everyday activities such as
fastening buttons and tying a shoe difficult. This
weakness then progresses up the arm. Weakness can also
begin in the feet and progress up the leg. Weakness in the
feet and ankles may first be noticed as frequent stumbling
or clumsiness. It leads to a condition called foot drop,
in which the feet drag when the patient walks. Over time,
the patient experiences muscle cramps, spasms, and
tremors. When muscles in the throat are affected, speech
becomes slurred or slowed, and the patient may have
difficulty swallowing. As the muscles of the diaphragm
weaken, a respirator is needed to help with breathing. ALS
does not affect mental function, the senses, bowel and
bladder function, or the eye muscles. Because ALS
progresses until it affects almost all the voluntary
muscle groups in the body, patients are eventually able to
move only their eyes. ALS is a fatal disease. Because the
weakened respiratory and swallowing muscles make it
difficult to cough and swallow food, the most likely cause
of death is lung infection caused by the inhalation of
food or saliva into the lungs, called aspiration.
How is it diagnosed?
ALS is diagnosed by a thorough physical examination and
a study of the patient’s medical history and pattern of
symptoms. While there is no specific diagnostic test for
ALS, the doctor will order tests of the brain and nervous
system to rule out other causes. A test called
electromyography (EMG) is used to measure the electrical
activity in the muscles, which will help determine if the
symptoms are caused by an abnormality in the nerves or
muscles. The doctor may also order blood and urine tests,
computed tomography (CT) scans, magnetic resonance imaging
(MRI) scans, and x-rays.
What is the treatment?
There is no cure for ALS. Patients in the beginning
stages of the disease should remain as active as possible.
Studies have shown that taking a drug called riluzole
early in the disease can slow the progression of symptoms
slightly. As symptoms progress, treatment involves
supporting the patient with physical therapy to prevent
muscle shortening (contractures), keep the muscles as
strong as possible, and maintain a good range of motion.
Drugs are available to reduce muscle cramping. A speech
pathologist can help with communication and swallowing
difficulties. It is extremely important that ALS patients
follow a special diet to prevent choking and aspiration of
food. Some patients must be fed through a gastrostomy
tube, which is inserted through the abdominal wall into
the stomach. Patients who become unable to breathe on
their own use a mechanical ventilator. Most ALS patients
eventually require full-time nursing care.
Self-care tips
It is difficult to maintain a positive outlook in the
face of ALS. For this reason, emotional support is
extremely important. If you have been diagnosed with ALS,
learn all you can about the disease and decide what type
of medical treatment is acceptable to you as the disease
progresses. Make sure your healthcare provider, family,
and friends are aware of your choices.
Physician's Who Treat ALS
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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