Allan Herndon Syndrome

Important

It is possible that the main title of the report Allan Herndon Syndrome 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

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• X-Linked Mental Retardation with Hypotonia
• Allan-Herndon-Dudley Syndrome
• AHDS
• Allan-Herndon-Dudley Mental Retardation

Disorder Subdivisions

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• None

General Discussion

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Allan-Herndon syndrome is an extremely rare inherited disorder that may be characterized by severe mental retardation, an impaired ability to form words and speak clearly (dysarthria), diminished muscle tone (hypotonia), and/or movement abnormalities.



With the exception of poor muscle tone, most affected infants appear to develop normally during the first months of life. However, by about six months of age, affected infants may seem weak and have an inability to hold up the head. Due to hypotonia, severely reduced motor development, and other abnormalities, affected children may not develop the ability to walk or may walk with difficulty. Associated features often include underdevelopment (hypoplasia) and wasting (atrophy) of muscle tissue; weakness and stiffness of the legs (spastic paraplegia) with exaggerated reflexes (hyperreflexia); relatively slow, involuntary, purposeless, writhing movements (athetoid movements); and/or other movement abnormalities. Affected individuals may also have abnormalities of the skull and facial (craniofacial) region. Allan-Herndon syndrome is thought to be inherited as an X-linked recessive trait and therefore is typically fully expressed in males only.

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Resources

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WE MOVE (Worldwide Education and Awareness for Movement Disorders)

204 West 84th Street

New York, NY 10024

USA

Tel: 2128758312

Fax: 2128758389

Email: wemove@wemove.org

Internet: http://www.wemove.org



The Arc (a national organization on mental retardation)

1010 Wayne Ave

Suite 650

Silver Spring, MD 20910

Tel: (301)565-3842

Fax: (301)565-3843

Tel: (800)433-5255

TDD: (817)277-0553

Email: info@thearc.org

Internet: http://www.thearc.org/



NIH/Nat'l Institute on Deafness & Other Communication Disorders Information Clearinghouse

1 Communication Ave

Bethesda, MD 20892-3456

Tel: (301)402-0900

Fax: (301)907-8830

Tel: (800)241-1044

TDD: (800)241-1105

Email: nidcdinfo@nidcd.nih.gov

Internet: http://www.nidcd.nih.gov

For a Complete Report

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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

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:   10/24/2003

Copyright   1996, 2001, 2003 National Organization for Rare Disorders, Inc.