Amyotrophic Lateral Sclerosis (ALS)

(Lou Gehrig's Disease; Motor Neuron Disease)

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Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention | Organizations

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Definition

Amyotrophic lateral sclerosis (ALS) is a progressive nervous system disorder. It gradually destroys the nerves responsible for muscle movement. Over time, ALS leads to total paralysis of muscle movement, including respiration.

Causes

The cause of ALS is not known, but it appears that genes may play a role in a very small number of cases.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

• Having a family member with ALS

Symptoms

Symptoms include:

• Progressive weakness in arms and legs (at first often on only one side)
• Trouble holding things without dropping them
• Frequent tripping while walking
• Shrunken muscles
• Twitchy muscles
• Overactive reflexes
• Slurred speech
• Hoarseness
• Trouble chewing and swallowing, resulting in frequent choking and gagging
• Weight loss due to trouble eating
• Trouble breathing
• Excess salivation, drooling
• Severe weight loss
• Trouble coughing, resulting in development of pneumonia

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam. There are no tests that definitively diagnose ALS, but tests may be used to rule out other medical conditions.

Tests may include:

• Electromyogram (EMG) – to look for progressive muscle weakness and twitching
• CT scan - a type of x-ray that uses a computer to make pictures of the structures inside the head
• MRI scan - a test that uses magnetic waves to make pictures of the structures inside the head
• Blood tests
• Urine tests

Treatment

There are currently no cures for ALS. A new drug called riluzole is being studied. It may slightly improve functioning for ALS patients, although it doesn't stop the disease progression. Another drug, mecasermin is also being researched.

Treatments for the symptoms of ALS include:

Valium, baclofen, or dantrolene - to reduce spasticity

Nonsteroidal anti-inflammatory drugs (such as ibuprofen) and anti-seizure medications - to reduce pain from muscle cramping

Physical therapy – to reduce pain associated with muscle cramping and spasticity

Atropine, scopolamine, or an antihistamine – to reduce heavy drooling

Antidepressants, anxiolytic drugs, and psychotherapy – to treat depression and anxiety

Prevention

There are no guidelines for preventing ALS because the cause is not known.

Organizations

American Academy of Neurology
http://www.aan.com

ALS Association
http://www.alsa.org/

SOURCES:

National Institute of Neurological Disorders and Stroke

Goetz: Textbook of Clinical Neurology, 1st ed. W. B. Saunders Company, 1999.

"Amyotrophic Lateral Sclerosis: Lou Gehrig's Disease," American Family Physician, March 15, 1999.

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Last reviewed June 2001 by Medical Review Board