Amyotrophic lateral sclerosis, or ALS, is a disease of the nerve cells in the brain and spinal cord that control voluntary muscle movement.
ALS is also known as Lou Gehrig's disease.
1 out of 10 cases of ALS are due to a genetic defect. The other times, the cause is unknown.
In ALS, nerve cells (neurons) waste away or die, and can no longer send messages to muscles. This eventually leads to muscle weakening, twitching, and an inability to move the arms, legs, and body. The condition slowly gets worse. When the muscles in the chest area stop working, it becomes hard or impossible to breathe.
ALS affects approximately 5 out of every 100,000 people worldwide.
There are no known risk factors, except for having a family member who has a hereditary form of the disease.
Symptoms usually do not develop until after age 50, but they can start in younger people. Persons with ALS have a loss of muscle strength and coordination that eventually gets worse and makes it impossible to do routine tasks such as going up steps, getting out of a chair, or swallowing.
Breathing or swallowing muscles may be the first muscles affected. As the disease gets worse, more muscle groups develop problems.
ALS does not affect the senses (sight, smell, taste, hearing, touch). It only rarely affects bladder or bowel function, eye movement, or a person's ability to think or reason.
The doctor or nurse will examine you and ask questions about your medical history and symptoms.
The physical exam may show:
Tests that may be done include:
There is no known cure for ALS. A medicine called riluzole helps slow down the symptoms and lets you live longer.
Treatments to control other symptoms include:
Physical therapy, rehabilitation, use of braces or a wheelchair, or other measures may be needed to help with muscle function and general health.
Choking is common. Patients may decide to have a tube placed into their stomach for feeding. This is called a gastrostomy.
A nutritionist is very important. Patients with ALS tend to lose weight. The illness itself increases the need for food and calories. At the same time, problems with swallowing make it hard to eat enough.
Breathing devices include machines that are used only at night, and constant mechanical ventilation.
Patients should discuss their wishes regarding artificial ventilation with their families and doctors.
Emotional support is vital in coping with the disorder, because mental functioning is not affected. Groups such as the ALS Association may be available to help people who are coping with the disorder.
Support for people who are caring for someone with ALS is also available, and may be very helpful.
See: ALS - support group
Over time, people with ALS progressively lose the ability to function and care for themselves. Death often occurs within 3 - 5 years of diagnosis. About 1 in 4 patients survive for more than 5 years after diagnosis.
Call your health care provider if:
Increased difficulty swallowing, difficulty breathing, and episodes of apnea are symptoms that require immediate attention.
You may want to see a genetic counselor if you have a family history of ALS.
Lou Gehrig's disease; ALS; Upper and lower motor neuron disease; Motor neuron disease
Murray B, Mitsumoto H. Disorders of upper and lower motor neurons. In: Daroff RB, Fenichel GM, Jankovic J, eds. Bradley’s Neurology in Clinical Practice. 6th ed. Philadelphia, Pa: Saunders Elsevier; 2012:chap 74.
Shaw PJ. Amyotrophic lateral sclerosis and other motor neuron diseases. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 418.
Updated by: Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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