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Hyperexplexia

National Organization for Rare Disorders, Inc.

Important
It is possible that the main title of the report Hyperexplexia is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.

Synonyms

  • Exaggerated Startle Reaction
  • Familial Startle Disease
  • Hyperekplexia
  • Kok Disease
  • Startle Disease

Disorder Subdivisions

  • None

General Discussion

Hyperexplexia is a rare autosomal dominant, hereditary, neurological disorder that may affect infants as newborns (neonatal) or prior to birth (in utero). It may also affect children and adults. Individuals with this disorder have an excessive startle reaction to sudden unexpected noise, movement, or touch. Symptoms include extreme muscle tension (stiffness or hypertonia) that can cause the affected person to fall stiffly, like a log, without loss of consciousness. Exaggeration of reflexes (hyperreflexia), and an unstable way of walking (gait) may also occur.

The treatment of hyperexplexia is relatively uncomplicated and involves the use of anti-anxiety and anti-spastic medicines. However, the disorder is frequently misdiagnosed as a form of epilepsy so that the process of getting an accurate diagnosis may be prolonged.

Resources

NIH/National Institute of Neurological Disorders and Stroke
P.O. Box 5801
Bethesda, MD 20824
Tel: (301)496-5751
Fax: (301)402-2186
Tel: (800)352-9424
TDD: (301)468-5981
Email: me20t@nih.gov
Internet: http://www.ninds.nih.gov/

MUMS National Parent-to-Parent Network
150 Custer Court
Green Bay, WI 54301-1243
USA
Tel: (920)336-5333
Fax: (920)339-0995
Tel: (877)336-5333
Email: mums@netnet.net
Internet: http://www.netnet.net/mums/

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223
Internet: http://rarediseases.info.nih.gov/GARD/

Movement Disorder Society
555 E. Wells Street
Suite 1100
Milwaukee, WI 53202-3823
Tel: (414)276-2145
Fax: (414)276-3349
Email: info@movementdisorders.org
Internet: http://www.movementdisorders.org

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

Last Updated:  5/22/2008
Copyright  1990, 1994, 1995, 2004 National Organization for Rare Disorders, Inc.

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