Diseases & Conditions


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Werdnig Hoffman Disease


Synonyms of Werdnig Hoffman Disease
  • Infantile Spinal Muscular Atrophy
  • SMA 1
  • SMA, Infantile Acute Form
  • Spinal Muscular Atrophy Type 1
  • Werdnig-Hoffman Paralysis

Disorder Subdivisions



    General Discussion
    The spinal muscular atrophies (SMAs), are characterized by degeneration of nerve cells (motor nuclei) within the lowest region of the brain (lower brainstem) and certain motor neurons in the spinal cord (anterior horn cells) leading to muscle weakness of the truncal, and extremity muscles initially, followed by chewing, swallowing and breathing difficulties. Motor neurons are nerve cells that transmit nerve impulses from the spinal cord or brain (central nervous system) to muscle or glandular tissue.

    Approximately 80 percent of individuals with SMA fall into the severe category (Werdnig-Hoffman disease or SMA1). Infants with SMA1 experience severe weakness before 6 months of age, and the patient never achieves the ability to sit independently when placed. Muscle weakness, lack of motor development and poor muscle tone are the major clinical manifestations of SMA1. Infants with the gravest prognosis have problems sucking or swallowing. Some show abdominal breathing in the first few months of life. Abdominal breathing is noted when the abdomen protrudes during inspiration. Normally, the chest expands during inspiration as the intercostal muscles (the muscles between the ribs) expand during inspiration. Abdominal breathing occurs when the intercostal muscles are weak and the diaphragm muscle is responsible for inspiration. Movement of the diaphragm (the muscle between the chest and abdomen) expands causing the abdomen to move during the inspiration cycle. A twitching of the tongue is often seen. Cognitive development is normal. Most affected children die before 2 years of age but survival may be dependent on the degree of respiratory function and respiratory support.

    The different subtypes, SMA 0-4 are based on the age of onset of symptoms and the course and progression of the disease. SMA represents a continuum or spectrum of disease with a mild end and a severe end. SMA0 patients are extremely weak a birth, require immediate artificial ventilation and will never breathe independently. Werdnig-Hoffman disease, which is also known as spinal muscular atrophy type 1 (SMA1) or acute spinal muscular atrophy, refers to individuals who have symptom onset prior to 6 months of age. SMA 2 patients will show symptoms prior to age 1 year, will sit but never walk. SMA 3 patients (Kugelberg-Welander disease) will show symptoms after age 1, and will walk for a period of time prior to loss of motor abilities. SMA 4 patients will not develop symptoms much before age 10 years.

    All the SMAs are inherited as an autosomal recessive trait. Molecular genetic testing has revealed that all types of autosomal recessive SMA are caused by disruptions or errors (mutations) in the SMN1 (survival motor neuron 1) gene on chromosome 5

    Organizations related to Werdnig Hoffman Disease
    • Families of Spinal Muscular Atrophy
      P.O. Box 196
      Libertyville IL 60048
      Phone #: 847-367-7620
      800 #: 800-886-1762
      e-mail: sma@fsma.org
      Home page: http://www.curesma.com
    • FightSMA (Andrew's Buddies)
      1807 Libbie Avenue
      Richmond VA 23226
      Phone #: 804-515-0080
      800 #: N/A
      e-mail: heatherlennon@fightsma.com
      Home page: http://www.FightSMA.org .org
    • Jennifer Trust for Spinal Muscular Atrophy
      Elta House
      Warwickshire None CV37 0AQ
      Phone #: 087-0 7-743651
      800 #: --
      e-mail: jennifer@jtsma.org.uk
      Home page: http://www.jtsma.org.uk
    • MUMS (Mothers United for Moral Support, Inc) National Parent-to-Parent Network
      150 Custer Court
      Green Bay WI 54301-1243
      Phone #: 920-336-5333
      800 #: 877-336-5333
      e-mail: mums@netnet.net
      Home page: http://www.netnet.net/mums/
    • Madisons Foundation
      PO Box 241956
      Los Angeles CA 90024
      Phone #: 310-264-0826
      800 #: N/A
      e-mail: getinfo@madisonsfoundation.org
      Home page: http://www.madisonsfoundation.org
    • March of Dimes Birth Defects Foundation
      1275 Mamaroneck Avenue
      White Plains NY 10605
      Phone #: 914-428-7100
      800 #: 888-663-4637
      e-mail: Askus@marchofdimes.com
      Home page: http://www.marchofdimes.com
    • Muscular Dystrophy Association
      3300 E. Sunrise Dr
      Tucson AZ 85718
      Phone #: 520-529-2000
      800 #: 800-344-4863
      e-mail: mda@mdausa.org
      Home page: http://www.mdausa.org
    • Muscular Dystrophy Campaign
      7-11 Prescott Place
      London None SW4 6BS
      Phone #: N/A
      800 #: --
      e-mail: info@muscular-dystrophy.org
      Home page: http://www.muscular-dystrophy.org
    • National Institute of Neurological Disorders and Stroke (NINDS)
      31 Center Drive
      Bethesda MD 20892-2540
      Phone #: 301-496-5751
      800 #: 800-352-9424
      e-mail: braininfo@ninds.nih.gov
      Home page: http://www.ninds.nih.gov/



    For a Complete Report

    This is an abstract of a report from the National Organization for Rare Disorders, Inc. ? (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html