OHSU

About ALS

Amyotrophic lateral sclerosis (ALS) is also known as Lou Gehrig's disease, after the famous baseball player who had it. It is a progressive neurodegenerative disorder (affects the nerves and gets worse over time).

In healthy people, cells in the spinal cord and brain called motor neurons control the voluntary muscles (muscles you can control). In people with ALS, these motor neurons break down. The nerve signal that reaches the muscles gets weaker over time. Since electrical signals from the nerves normally maintain muscle mass, the affected muscles shrink and get weaker as these signals decrease.

The OHSU ALS and Neuromuscular Disease Center provides the most advanced care for people with ALS. Our doctors are experts in treating this condition.

Symptoms of ALS

The first symptom of ALS is muscle weakness that gets worse over several months. Muscle weakness is the main symptom of this disorder.

If weakness occurs in the arms or legs first, the disorder is called limb-onset ALS. If difficulty swallowing or speaking is the first symptom, the disorder is called bulbar-onset ALS. With both types, the weakness spreads to other areas of the body with time. Eventually, it causes paralysis.

Other ALS symptoms include:

  • Muscle stiffness, twitching and cramps
  • Exaggerated reflexes (automatic muscle)

ALS can cause pain from muscle cramps, loss of muscle strength and loss of mobility (ability to move around freely). Eye movements, bladder and bowel control and sexual function are not usually affected. ALS does not usually affect the senses of touch, vision and hearing.

Causes of ALS

The cause of ALS is unknown. Research has not shown it is caused by anything in the environment or by aging. In some cases, genetics (heredity) may be involved. Researchers have found at least one defective gene that might make ALS more likely, but they don't yet understand exactly how this gene works.

Even though having a defective gene might make ALS more likely, this disorder has not been shown to run in families. Only 5 percent of people with  ALS have a family member who also has the disease. Most people with ALS have sporadic ALS, meaning it happened without any known cause.

About one in every 10,000 Americans has ALS. ALS is not contagious, so you can't catch the disorder from someone who has it.

Diagnosing ALS

ALS is usually difficult to diagnose. If you think you might have ALS, you need to see a doctor who has experience with this disorder. The doctor does a variety of tests and examinations, including:

  • Taking your complete medical history
  • Doing a complete physical examination, including a neurological examination (examination of your nerve responses and reflexes)
  • Doing an electromyelogram (EMG) test  to measure the electrical signals reaching your muscles

You might also have blood tests, imaging tests (CT, MRI or other scans)  and muscle biopsies to make sure you do not have a different disorder.  

Prognosis for People with ALS

ALS develops differently in each person, and everyone makes different treatment choices. At the OHSU ALS and Neuromuscular Disease Center, we provide the most advanced treatment for ALS, and bring experts from around OHSU together to care for you and your family.

If you have ALS, we encourage you and your family to plan for the future by being informed, taking advantage of your treatment options and completing an advance directive so your family and healthcare team have complete instructions about your care.