About Bleeding Disorders.
Bleeding disorders are a group of disorders that share the inability to form a proper blood clot. Symptoms include extended bleeding after injury, surgery, trauma, or menstruation. Sometimes the bleeding is spontaneous, without a known or identifiable cause. Improper clotting can be caused by defects in blood components such as platelets and/or clotting proteins, also called clotting factors. The body produces 13 clotting factors. If any of them are defective or deficient, blood clotting is affected; a mild, moderate or severe bleeding disorder can result.
Some bleeding disorders, such as hemophilia, can be inherited or acquired. Others can occur from such conditions as anemia, cirrhosis of the liver, HIV, leukemia, and vitamin K deficiency. They also can result from certain medications that thin the blood, including aspirin, heparin, and warfarin.
Hemophilia occurs predominantly in males, but can occur in women. In about one-third of cases the disorder results from a spontaneous genetic mutation rather than by a family history of hemophilia. Hemophilia treatment may require life-long infusion of clotting factor based on the severity of the disorder. Average hemophilia treatment costs between $60,000 and $260,000 per year. Early recognition and prompt treatment of bleeds can help keep these costs down as well as reduce disability.von Willebrand Disease is a bleeding disorder caused by a defect or deficiency of a blood clotting protein, called von Willebrand Factor. The disease is estimated to occur in 1% of the population; many are undiagnosed. vWD is a genetic disease that can be inherited from either parent. It affects males and females equally. A man or woman with VWD has a 50% chance of passing the gene on to his or her child. There are no racial or ethnic associations with the disorder. A family history of a bleeding disorder is the primary risk factor.Other Factor Deficiencies: There are ten clotting factors that are necessary in forming a blood clot. Deficiencies in factors VIII and IX are well known to most people, but what of the other factor deficiencies? Not everyone is as familiar with these conditions because they are diagnosed so rarely. To date, deficiencies in eight of the lesser known coagulation factors have been documented in the medical literature. Many of these disorders were only discovered or described within the last 40 years.
-
Hemophilia A, also called factor VIII (8) deficiency or classic hemophilia, is a genetic disorder caused by missing or defective factor VIII (FVIII), a clotting protein. Although it is passed down from parents to children, about 1/3 of cases found have no previous family history.
According to the US Centers for Disease Control and Prevention (CDC), hemophilia occurs in approximately 1 in 5,617 live male births. There are between 30,000 – 33,000 males with hemophilia in the US*. More than half of people diagnosed with hemophilia A have the severe form. Hemophilia A is four times as common as hemophilia B. Hemophilia affects all races and ethnic groups.
Severity
(percentage breakdown of overall hemophilia population by severity)
• Severe (factor levels less than 1%) represent approximately 60% of cases
• Moderate (factor levels of 1-5%) represent approximately 15% of cases
• Mild (factor levels of 6%-30%) represent approximately 25% of cases
-
Hemophilia B, also called factor IX (FIX) deficiency or Christmas disease, is a genetic disorder caused by missing or defective factor IX, a clotting protein. Although it is passed down from parents to children, about 1/3 of cases are caused by a spontaneous mutation, a change in a gene.
According to the US Centers for Disease Control and Prevention, hemophilia occurs in approximately 1 in 5,000 live births. There are between 30,000 – 33,000 people with hemophilia in the US. All races and ethnic groups are affected. Hemophilia B is four times less common than hemophilia A.
-
Von Willebrand disease (VWD) is an inheritable bleeding disorder. Many different proteins are needed to make a person’s blood clot successfully. People with VWD are either missing or low in the clotting protein von Willebrand factor (VWF) – or it doesn’t work as it’s supposed to. For a person to make a successful clot, VWF binds to factor VIII (8), another clotting protein, and platelets in blood vessel walls. This process will help form a platelet plug during the clotting process. People with VWD are not able to form this platelet plug, or it will take longer to form. The condition is named after Finnish physician Erik von Willebrand, who first described it in the 1920s.
VWD is the most common bleeding disorder, affecting up to 1% of the US population – or approximately 1 in every 100 people. It occurs equally in men and women. However, women may be more symptomatic due to heavy menstrual bleeding (periods). VWD occurs equally across all races and ethnicities.
-
In the US, a rare disease or disorder is defined as one that affects fewer than 200,000 people. This means hemophilia A and B, and the less-common factor deficiencies such as I, II, V, VII, X, XI, XII and XIII, are all rare disorders.
Blood clotting is a complex process, involving many different proteins, called factors, each of which plays a different role in the blood clotting process. Factor deficiencies are defined by which specific clotting protein in the blood protein is low, missing or doesn't work properly.
Factor I (1) Deficiency
Factor I deficiency is a collective term for three rare inherited fibrinogen deficiencies. One of these, afibrinogenemia is very rare, occurring in 1-2 people per million.
Factor II (2) Deficiency
Factor II deficiency is estimated to occur in 1 out of every 2 million people.
Factor V (5) Deficiency
Factor V deficiency is estimated to occur in 1 out of every 2 million people.
Factor VII (7) Deficiency
Factor VII deficiency is estimated to occur in 1 out of every 300,000-500,000 people. That makes it the most common of the rare factor deficiencies.
Factor X (10) Deficiency
Factor X deficiency is estimated to occur in 1 in 500,000 to 1 in a million people.
Factor XI (11) Deficiency (Hemophilia C)
Factor XI deficiency is estimated to occur in 1 in 100,000 people.
Factor XII (12)
Factor XII deficiency is estimated to occur in 1 in a million people.
Factor XIII (13) Deficiency
Factor XIII deficiency is estimated to occur in 1 in 5 million people. It is the rarest of the rare factor deficiencies.
