Motor Neuron
Disease
Maladie de
Charcot
Lou Gehrig's Disease
What is the
Disease?
ALS is an extremely deadly disease affecting
the nerve cells that control the victim's voluntary muscles. These nerves shrink and eventually die,
leaving the muscles without stimulation.
As these muscles go without stimulation, they too eventually shrink and
die. The victim progressively weakens to
the point of complete paralysis of all voluntary muscles and some involuntary
muscles, such as breathing and swallowing, and soon after this point, death is
inevitable.
'A' means
"Without"
'Myo' means
"Muscle"
'Trophic' means
"Nourishment"
'Lateral'
refers to uneven development of symptoms
between right and left sides
'Sclerosis'
refers to
"destruction" of tissue
The History of
ALS
A French doctor named Charcot first identified
ALS in 1874. It is one of the most
devastating diagnoses a person can receive.
ALS is said to start between the years of 40 and 70, with the exact
average being 45.6 years old.
The most classic
case of Amyotrophic Lateral Sclerosis is Lou Gehrig. Lou Gehrig was a New York Yankees first
baseman, who from 1923 to 1939, had never missed a game and had a life time
batting average of .340. However, the
symptoms of ALS emerged in 1938, and in 1939, he was diagnosed with the
disease. At that time doctors knew
little to nothing about the disease and the only suggested treatment was the
untested vitamin E. So Gehrig ate a
daily plate full of garden grass, until June 2, 1941 when he died at the age of
37.
ALS affects approximately 1 out of every
100,000 people. In the United States
there are around 30,000 Americans affected by ALS, and 3,000 more are diagnosed
with the disease each year, with men being affected slightly more than women,
and in some cases, running in families.
However while this is the same number of new cases as Multiple
Sclerosis, Multiple Sclerosis affects around 350,000 Americans. The difference is that 50% of ALS patient's
die within three years, and 80% die within five. The disease is in some ways quite similar to
Alzheimer's except with Alzheimer's you have a body walking around with a
diseased brain, whereas with ALS you have a healthy brain trapped inside a diseased
body.
Symptoms
About
one-third of those with ALS become aware of their disease when their hands
become clumsy, causing difficulty performing anything needing fine finger
movements. Another third find a weakness
in their legs and may trip because of a mild foot drop. The remaining one-third notice slurring in
their speech or difficulty swallowing.
Because all of these symptoms happen naturally, it is generally not
characterized as ALS until the symptom progressively worsens. This happens as the affected area's muscle
cells deteriorate, resulting in muscle tenseness. Frequently one side of the body is affected
first and it then gradually passes to the other side. Muscles in the eyes, anus and bladder are
generally left unaffected.
Diagnoses
As there is no known way to prevent this
disease, there is also no specific clinical test to identify ALS. It generally involves a physical examination,
perusing through the patient's medical history, and neurological testing. To test muscle activity specialists often use
an EMG, or electromyogram, and will often use CT scans, MRIs, and thorough
blood examination. There is also a
recently developed SOD1 scan, the gene now thought to be the cause for ALS,
especially familial ALS. Only 20%,
however, of patients with familial ALS show positive on the SOD1 scan.
Progress of ALS
Until very recently very little was known about
ALS, either what started it or how to treat it. Currently there are 3 types of ALS: classic
(sporadic), familial, and the Mariana Island.
Classic ALS accounts for 90-95% of ALS patients
in the U.S. The infrequent familial form (FALS) is inherited and if your
parents had FALS there is a 50/50 chance you will have it as well. The Mariana Island form is a rare form of ALS
found in patients taken from Guam and Japan.
ALS appears evenly across the globe except in the Mariana Islands in the
West Pacific and the Kii Peninsula of Japan where it is unusually high.
Back during Gehrig's time little else besides
vitamin E was even considered a "potential" therapy, and there were
only guesses as to the cause of the disease until 1991 when evidence linked
FALS to chromosome 21. Then in 1993 the
same research team identified a defective SOD1 gene on chromosome 21 as being responsible. It is now known that structural defects in
the Super Oxide Dismutase, or SOD, enzyme reduces the ability to protect
against damage to motor neurons.
Treatment
Traditionally doctors were unable to subscribe
anything other than a good source of Vitamin E, exercise and a healthy
mind. However, in June of 1996 the Food
and Drug Administration passed the first drug for ALS. The drug Riluzole was successful in lengthening
the life-time of ALS patients, especially those with FALS. However, there is still no way to dampen the
symptoms or prevent those who don't have it, from getting it. This still was a big step for ALS and there
are now 21 countries that have approved Riluzole, including the Czech Republic
and all 15 members of the European Union.
Gabapentin is also similar to Riluzole and is being tested for approval
by the FDA. More importantly, a drug
known as Myotrophin is being tested as well by the FDA and may be the first
drug to slow the progress of paralysis.
Because Myotrophin acts differently than Riluzole, they, hopefully, can
be used in synch as well.
Rescources
Science News,
Vol. 145, page 202
The Sacramento
Bee, March 2, 1994, A8
The Sacramento
Bee, June 9, 1996
The Wall Street
Journal, June 13, 1995, B7
Applied Medical
Informatics (AMI), 1994
Muscular
Dystrophy Association (MDA), January 31, 1996
The New York
Times, May 9, 1995
The New York
Times, June 13, 1995
Gene Therapy,
March 1995
Mayo Clinic
Health Letter, April 1996, page 5
Rhone-Poulenc
Rorer, August 1995
The ALS
Association and the Neuromuscular Research Foundation
Internet Sites:
http://www.caregiver.org/fs/fs_als.html
http://www.medicinenet.com/
http://www.phoenix.net/~jacobson/guide2.html
http://www.familyvillage.wisc.edu/lib_als.htm
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