Hemophilia Health Channel

	Feature Article Illustrations for this article Click on an image below to enlarge Blood clots Hemophilia A Definition Hemophilia A is a hereditary bleeding disorder caused by a lack of blood clotting factor VIII. Causes, incidence, and risk factors Hemophilia A results from a deficiency (lack) of clotting factor VIII. The disorder is caused by an inherited X-linked recessive trait, with the defective gene located on the X chromosome. Females have two copies of the X chromosome, so if the factor VIII gene on one chromosome doesn't work, the gene on the other chromosome can do the job of making enough factor VIII. Males, however, have only one X chromosome, so if the factor VIII gene on that chromosome is broken, they will have hemophilia A. Thus, most people with hemophilia A are male. If a woman has a defective factor VIII gene, she is considered a carrier. This means the defective gene can be passed down to her children. In a woman who carries the defective gene, any of her male children will have a 50% chance of having hemophilia A, while any of her female children will have a 50% chance of being a carrier. All female children of men with hemophilia carry the defective gene. Genetic testing is available for concerned parents. The severity of symptoms can vary. Severe forms become apparent early on. Bleeding is the main symptom of the disease and sometimes, though not always, occurs if an infant is circumcised. Additional bleeding problems are seen when the infant starts crawling and walking. Continue reading this article

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Hemophilia B (5 Images) (Doctor-Reviewed information)
Hemophilia B is a hereditary blood coagulation disorder. It is caused by a deficiency of a blood plasma protein called factor IX. Without enough factor IX, the blood cannot clot properly to control bleeding. Reviewer: Stephen Grund, MD, PhD, Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/21/2008
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Von Willebrand disease (2 Images) (Doctor-Reviewed information)
Von Willebrand disease is the most common hereditary bleeding disorder. Reviewer: Stephen Grund, M.D. Ph.D., Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/21/2008
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Platelet count (Doctor-Reviewed information)
A platelet count is a test to measure how many blood cells, called platelets, you have in your blood. Platelets help the blood clot. Reviewer: Mark Levin, MD, Hematologist and Oncologist, Newark, NJ. Review provided by VeriMed Healthcare Network.Date: 03/08/2007
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Vitamin K (2 Images) (Doctor-Reviewed information)
Vitamin K is a fat-soluble vitamin that plays an important role in blood clotting. The body can store fat-soluble vitamins in fatty tissue. Reviewer: William McGee, M.D., M.H.A., Assistant Professor of Medicine and Surgery, Tufts University School of Medicine, Boston, MA, and Chairman, Nutrition Committee, Baystate Medical Center, Springfield, MA. Review provided by VeriMed Healthcare Network.Date: 01/02/2007
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Bleeding disorders (Doctor-Reviewed information)
Bleeding disorders are a group of conditions involving the body's blood clotting process. Such disorders can lead to heavy and prolonged bleeding after an injury. Reviewer: Mark Levin, M.D., Hematologist and Oncologist, Newark, NJ. Review provided by VeriMed Healthcare Network.Date: 03/13/2007
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National Hemophilia Month: Project Red Flag. in Health Observances - 259 days ago

Hemophilia and inherited blood disorders primarily strike men, but women are vulnerable too. (NHF) campaign to raise awareness about women's bleeding disor... Email  |  Save