ALS (Amyotrophic Lateral Sclerosis)

What is ALS?

Amyotrophic lateral sclerosis (ALS), often referred to as "Lou Gehrig's Disease," is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. Motor neurons reach from the brain to the spinal cord and from the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their death. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, patients in the later stages of the disease may become totally paralyzed.

A-myo-trophic comes from the Greek language. "A" means no or negative. "Myo" refers to muscle, and "Trophic" means nourishment–"No muscle nourishment." When a muscle has no nourishment, it "atrophies" or wastes away. "Lateral" identifies the areas in a person's spinal cord where portions of the nerve cells that signal and control the muscles are located. As this area degenerates it leads to scarring or hardening ("sclerosis") in the region.

As motor neurons degenerate, they can no longer send impulses to the muscle fibers that normally result in muscle movement. Early symptoms of ALS often include increasing muscle weakness, especially involving the arms and legs, speech, swallowing or breathing. When muscles no longer receive the messages from the motor neurons that they require to function, the muscles begin to atrophy (become smaller). Limbs begin to look "thinner" as muscle tissue atrophies.

Initial Symptoms of the Disease

At the onset of ALS the symptoms may be so slight that they are frequently overlooked. With regard to the appearance of symptoms and the progression of the illness, the course of the disease may include the following:

• muscle weakness in one or more of the following: hands, arms, legs or the muscles of speech, swallowing or breathing
• twitching (fasciculation) and cramping of muscles, especially those in the hands and feet
• impairment of the use of the arms and legs
• "thick speech" and difficulty in projecting the voice
• in more advanced stages, shortness of breath, difficulty in breathing and swallowing

The initial symptoms of ALS can be quite varied in different people. One person may experience tripping over carpet edges, another person may have trouble lifting and a third person's early symptom may be slurred speech. The rate at which ALS progresses can be quite variable from one person to another. Although the mean survival time with ALS is three to five years, many people live five, ten or more years. In a small number of people, ALS is known to remit or halt its progression, though there is no scientific understanding as to how and why this happens. Symptoms can begin in the muscles of speech, swallowing or in the hands, arms, legs or feet. Not all people with ALS experience the same symptoms or the same sequences or patterns of progression. But, progressive muscle weakness and paralysis are universally experienced.

Muscle weakness is a hallmark initial sign in ALS, occurring in approximately 60% of patients. Early symptoms vary with each individual, but usually include tripping, dropping things, abnormal fatigue of the arms and/or legs, slurred speech, muscle cramps and twitches and/or uncontrollable periods of laughing or crying.

The hands and feet may be affected first, causing difficulty in lifting, walking or using the hands for the activities of daily living such as dressing, washing and buttoning clothes.

As the weakening and paralysis continue to spread to the muscles of the trunk of the body the disease, eventually affects speech, swallowing, chewing and breathing. When the breathing muscles become affected, ultimately, the patient will need permanent ventilatory support in order to survive.

Since ALS attacks only motor neurons, the sense of sight, touch, hearing, taste and smell are not affected. For many people, muscles of the eyes and bladder are generally not affected.

Diagnosing ALS

ALS is a very difficult disease to diagnose. To date, there is no one test or procedure to ultimately establish the diagnosis of ALS. It is through a clinical examination and series of diagnostic tests, often ruling out other diseases that mimic ALS, that a diagnosis can be established. A comprehensive diagnostic workup includes most, if not all, of the following procedures:

• electrodiagnostic tests including electomyography (EMG) and nerve conduction velocity (NCV)
• blood and urine studies including high resolution serum protein electrophoresis, thyroid and parathyroid
• ormone levels and 24 hour urine collection for heavy metals
• spinal tap
• x-rays, including magnetic resonance imaging (MRI)
• myelogram of cervical spine
• muscle and/or nerve biopsy
• thorough neurological examination

Facts You Should Know About ALS

The onset of ALS is insidious with muscle weakness or stiffness as early symptoms. Progression of weakness, wasting and paralysis of the muscles of the limbs and trunk as well as those that control vital functions such as speech, swallowing and later breathing generally follows. ALS is not contagious.

It is estimated that ALS is responsible for nearly two deaths per hundred thousand population annually.
Approximately 5,600 people in the U.S. are diagnosed with ALS each year. The incidence of ALS is two per 100,000 people, and it is estimated that as many as 30,000 Americans may have the disease at any given time.

Although the life expectancy of an ALS patient averages about two to five years from the time of diagnosis, this disease is variable and many people live with quality for five years and more. More than half of all patients live more than three years after diagnosis.

About twenty percent of people with ALS live five years or more and up to ten percent will survive more than ten years and five percent will live 20 years. There are people in whom ALS has stopped progressing and a small number of people in whom the symptoms of ALS reversed. ALS occurs throughout the world with no racial, ethnic or socioeconomic boundaries.

ALS can strike anyone.

Medical information obtained from our website is not intended as a substitute for professional care. If you have or suspect you have a problem, you should consult a healthcare provider.

More information available at: http://www.alsa.org/als/what.cfm

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