Amyotrophic Lateral Sclerosis (ALS), or Lou Gehrig's disease, is a nervous system disorder that results in severe muscle weakness, paralysis and eventually death. ALS attacks motor neurons, or nerve cells, in the brain and the spinal cord, disrupting the transmission of messages from the brain and spinal cord to the muscles. There is no cure for ALS.
Significance
The ALS Association estimates that 5,600 people in the U.S. are diagnosed with ALS each year. The life expectancy of individuals with ALS is 2 to 5 years after the diagnosis, although some individuals live and retain quality of life for five years or more after diagnosis. More than half of all people diagnosed with ALS live three years or more. The disease usually strikes between the ages of 40 and 60 and more men than women are diagnosed with ALS.
Causes
Why ALS occurs in some individuals and not others is not known. The Mayo Clinic estimates 1 in 10 cases of ALS is inherited. In 1993, The National Institute of Neurological disorders and stroke discovered mutations in a gene associated with cases of inherited ALS. Scientist are not clear how the gene mutation leads to ALS, but the gene isolated produces an enzyme that protects the body from DNA and protein damage in the cells from free radicals. Scientists hypothesize that the faulty gene causes free radicals to accumulate, resulting in ALS.
Individuals with ALS have higher levels of glutamate, a chemical messenger, in the spinal fluid. High levels of glutamate for long periods of time is toxic to and damages nerve cells. The National Institute of Neurological Disorders and Stroke reports scientists are investigating what causes a build-up of glutamate and how it relates to the development of ALS.
ALS might also be the result of an autoimmune response. Autoimmune responses cause an individual's immune system to start attacking his own cells, damaging motor neurons which interferes with the normal transmission of signals between the brain to the muscles, The National Institute if Neurological Disorders and Stroke states.
Symptoms
Early symptoms of ALS are often overlooked. The Mayo Clinic states early symptoms of ALS include hand weakness or clumsiness; tripping over things; weakness in the legs, foot and ankles; slurring of speech; muscle cramps or twitching in the tongue, arms and shoulder; trouble swallowing; and difficulty lifting the front part of the foot and toes. Muscles become weaker as the disease progresses and individuals with ALS eventually become paralyzed. Speaking, chewing, swallowing and breathing are also affected.
Diagnosis
ALS has symptoms resembling other neurological disorders, which makes it difficult to diagnose. A thorough physical exam and tests including an x-ray of the brain or MRI, spinal tap, muscle biopsy, muscle testing and blood and urine tests help rule out other diseases.
Treatment
There isn't a cure for ALS. Treatment focuses on symptom management and maintaining quality of life. Riluzole, a medication that reduces glutamate levels, is the first FDA approved medication for treating ALS. Riluzol doesn't cure ALS, but it can slow the progression of the disease in some people and delay the need for the insertion of a breathing tube. Other medications can help muscle cramps, constipation, pain and depression. Physical therapy exercises can help an individual with ALS maintain muscle strength and range of motion for a longer period of time, The Mayo Clinic states. Speech therapy can help strengthen the muscles that are used while speaking which minimizes slurring and makes speech easier to understand. As the disease progresses, a speech therapist can help with finding alternative ways to communicate. Occupational therapy can help with learning to use adaptive equipment such as cans, wheelchairs and braces.
