NINDS Spinal Muscular Atrophy Information Page

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Synonym(s):   Werdnig-Hoffman Disease, Kugelberg-Welander Disease
Condensed from Spinal Muscular Atrophy Fact Sheet

Table of Contents (click to jump to sections)
What is Spinal Muscular Atrophy?
Is there any treatment?
What is the prognosis?
What research is being done?

Organizations
Additional resources from MEDLINEplus

What is Spinal Muscular Atrophy?

Spinal Muscular Atrophy (SMA) Types I, II, and III belong to a group of hereditary diseases that cause weakness and wasting of the voluntary muscles in the arms and legs of infants and children. The disorders are caused by an abnormal or missing gene known as the survival motor neuron gene (SMN1), which is responsible for the production of a protein essential to motor neurons. Without this protein, lower motor neurons in the spinal cord degenerate and die. The type of SMA (I, II, or III) is determined by the age of onset and the severity of symptoms. Type I (also known as Werdnig-Hoffman disease, or infantile-onset SMA) is evident at birth or within the first few months. Symptoms include floppy limbs and trunk, feeble movements of the arms and legs, swallowing difficulties, a weak sucking reflex, and impaired breathing. Type II (also known as juvenile SMA, intermediate SMA, or chronic SMA, has an onset between 6 and 18 months. Legs tend to be more impaired than arms. Children with Type II are usually able to sit without support if placed in position. Some may be able to stand or walk with help. Type III (also called Wolhlfart-Kugelberg-Welander disease, or mild SMA) can begin as early as the toddler years or as late as adolescence. Children can stand alone and walk, but may have difficulty getting up from a sitting position.

Is there any treatment?

There is no cure for SMA. Treatment consists of managing the symptoms and preventing complications.

What is the prognosis?

The prognosis is poor for babies with SMA Type I. Most die within the first two years. For children with SMA Type II, the prognosis for life expectancy or for independent standing or walking roughly correlates with how old they are when they first begin to experience symptoms - older children tend to have less severe symptoms Children with onset after 18 months are often able to walk and are fully functional for years before they need assistance. They may have a normal life expectancy.

What research is being done?

The Spinal Muscular Atrophy Project is an NINDS funded collaborative program focused on the development of drug therapies for the treatment of SMA. Experts from industry, academia, NINDS, and the U.S. Food and Drug Administration guide the program. The Project is accelerating the research process by identifying drugs already in use that increase the level of SMN protein in cultured cells, which are then used as potential leads for further drug discovery and clinical testing.

Select this link to view a list of studies currently seeking patients.

Organizations

FightSMA/Andrew's Buddies
1807 Libbie Avenue
Suite 104
Richmond, VA   23226
heatherlennon@fightsma.com
http://www.fightsma.org
Tel: 804-515-0080
Fax: 804-515-0081

Families of Spinal Muscular Atrophy
P.O. Box 196
Libertyville, IL   60048-0196
info@fsma.org
http://www.curesma.org
Tel: 847-367-7620 800-886-1762
Fax: 847-367-7623

Spinal Muscular Atrophy Foundation
888 Seventh Avenue
Suite 400
New York, NY   10019
info@smafoundation.org
http://www.smafoundation.org
Tel: 877-FUND-SMA (877-386-3762) 646-253-7100
Fax: 212-247-3079

Muscular Dystrophy Association
3300 East Sunrise Drive
Tucson, AZ   85718-3208
mda@mdausa.org
http://www.mda.org
Tel: 520-529-2000 800-344-4863
Fax: 520-529-5300



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National Institute of Neurological Disorders and Stroke
National Institutes of Health
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Last updated July 09, 2008