Synonyms

• AHF Deficiency
• AHG Deficiency
• Antihemophilic Factor Deficiency
• Classical Hemophilia
• Antihemophilic Globulin Deficiency
• Christmas Disease

Disorder Subdivisions

• Hemophilia A (Factor VIII Deficiency)
• Hemophilia C (Factor XI Deficiency)
• Hemophilia B (Factor IX Deficiency)

General Discussion

Hemophilia is a rare inherited blood clotting (coagulation) disorder caused by inactive or deficient blood proteins (usually factor VIII). Factor VIII is one of several proteins that enable the blood to clot. Hemophilia may be classified as mild, moderate, or severe. The level of severity is determined by the percentage of active clotting factor in the blood (normal percentage ranges from 50 to 150 percent). People who have severe hemophilia have less than one percent of active clotting factor in their blood.

There are three major types of hemophilia: hemophilia A (also known as classical hemophilia, factor VIII deficiency or antihemophilic globulin [AHG] deficiency); hemophilia B (Christmas disease or factor IX deficiency); and hemophilia C (factor XI deficiency). Hemophilia A and B are inherited as X-linked recessive genetic traits, while Hemophilia C is inherited as an autosomal recessive genetic trait. Therefore, while hemophilia A and B are fully expressed in males only, hemophilia C affects males and females in equal numbers.

Resources

March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
Tel: (914)997-4488
Fax: (914)997-4763
Tel: (888)663-4637
Email: Askus@marchofdimes.com
Internet: http://www.marchofdimes.com

National Hemophilia Foundation
116 West 32nd Street, 11th Floor
New York, NY 10001
USA
Tel: (212)328-3700
Fax: (212)328-3777
Tel: (800)424-2634
Email: handi@hemophilia.org
Internet: http://www.hemophilia.org

Canadian Hemophilia Society
400-1255 University Street
Montreal
Quebec, H3B 3B6
Canada
Tel: 514-848-0503
Fax: 514-848-9661
Tel: 800-668-2686
Email: chs@hemophilia.ca
Internet: http://www.hemophilia.ca

NIH/National Heart, Lung and Blood Institute
P.O. Box 30105
Bethesda, MD 20892-0105
Tel: (301)592-8573
Fax: (301)251-1223
Email: nhlbiinfo@rover.nhlbi.nih.gov
Internet: http://www.nhlbi.nih.gov/

World Federation of Hemophilia
1425 René Lévesque Blvd. W. Suite 1010
Montreal
Quebec, Intl H3G 1T7
Canada
Tel: +1 (514) 875-7944
Fax: +1 (514) 875-8916
Email: wfh@wfh.org
Internet: http://www.wfh.org/index.asp?lang=EN

Cochrane Cystic Fibrosis and Genetic Disorders Group
Institute of Child Health, University of Liverpool
Alder Hey Children's NHS Foundation Trust
Liverpool, L12 2 AP
United Kingdom
Tel: +44 151 252 5696
Email: nikkij@liverpool.ac.uk
Internet: http://cfgd.cochrane.org

Hemophilia Federation of America
210 7th St. SE
Suite 200B
Washington, DC 20003
USA
Tel: (202)675-6984
Fax: (202)675-6983
Tel: (800)230-9797
Email: info@hemophiliafed.org
Internet: http://www.hemophiliafed.org

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/

Irish Haemophilia Society
First Floor
Cathedral Court
New Street
Dublin, 7
Ireland
Tel: +353 (0)1 657 99 00
Fax: +353 (0)1 657 99 01
Email: info@haemophilia.ie
Internet: http://www.haemophilia.ie/

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:  10/10/2008
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