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 Videos, 3 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 (11 Videos) (Doctor-Reviewed information)
A platelet count is a test to measure how many platelets you have in your blood. Platelets help the blood clot. They are smaller than red or white blood cells.Reviewer: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. Date: 02/21/2009
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Vitamin K (11 Videos, 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: Linda Vorvick, MD, Family Physician, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/07/2009
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Bleeding disorders (11 Videos) (Doctor-Reviewed information)
Bleeding disorders are a group of conditions in which there is a problem with the body's blood clotting process. These disorders can lead to heavy and prolonged bleeding after an injury. Bleeding can also begin on its own. See also: Acquired plate...Reviewer: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/02/2009
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National Hemophilia Month: Project Red Flag in Health Observances -

Project Red Flag is the National Hemophilia Foundation's(NHF) campaign to raise awareness about women's bleeding disorders. 2.5 million women in the US hav... Email