What is amyotrophic lateral sclerosis (ALS)?
Amyotrophic lateral sclerosis (ALS) is a terminal neurological disorder characterized by progressive degeneration of nerve cells in the spinal cord and brain. Often referred to as "Lou Gehrig's disease" (a famous baseball player who died from the disease), it is one of the most devastating of the disorders that affects the function of nerves and muscles.
ALS does not affect mental functioning or the senses (such as seeing or hearing), and it is not contagious. Currently, there is no cure for amyotrophic lateral sclerosis.
Statistics of ALS
Consider the following statistics regarding ALS:
Most people who develop ALS are between the ages of 40 and 70, although the disease can occur at a younger age.
ALS occurs throughout the world with no racial, ethnic, or socioeconomic boundaries.
ALS affects as many as 30,000 Americans, with 5,600 new cases diagnosed in the US each year.
What are the different types of ALS?
There are three known classifications of ALS, including the following:
Sporadic - The most common form of ALS in the US, involving 90 percent to 95 percent of all cases. These cases occur randomly, without any known cause, and there is no association with persons in the family with the disease.
Familial - Suggests that the disease is inherited and accounts for a very small number of cases in the United States, about 5 percent to 10 percent.
Guamanian - An extremely high incidence of ALS was observed in Guam and the Trust Territories of the Pacific in the 1950s.
What are the symptoms of ALS?
Patients who suffer from ALS initially experience weakness in one of their limbs that develops over a matter of days or, more commonly, a few weeks. Then, several weeks to months later, weakness develops in another limb. Sometimes the initial problem can be one of slurred speech or difficulty swallowing.
As ALS progresses, though, more and more symptoms are noticed. The following are the most common symptoms of ALS. However, each individual may experience symptoms differently. Symptoms may include:
Twitching and cramping of muscles, especially those in the hands and feet
Loss of motor control in the hands and arms
Impairment in the use of the arms and legs
Tripping and falling
Uncontrollable periods of laughing or crying
Slurred or thick speech and difficulty in projecting the voice
As the disease progresses, symptoms may include:
The symptoms of ALS may resemble other conditions or medical problems. Always consult your physician for a diagnosis.
How is ALS diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for ALS may include the following:
Laboratory tests (including blood and urine studies and thyroid functioning tests)
Muscle and/or nerve biopsy - a procedure performed to remove tissue or cells from the body for examination under a microscope
Spinal tap (also called a lumbar puncture) - a special needle is placed into the lower back, into the spinal canal; This is the area around the spinal cord; The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes the brain and spinal cord.
X-ray - a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film
Magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body
Electrodiagnostic tests (i.e., electromyography (EMG) and nerve conduction study, or NCS) - studies that evaluate and diagnose disorders of the muscles and motor neurons; Electrodes are inserted into the muscle, or placed on the skin overlying a muscle or muscle group, and electrical activity and muscle response are recorded.