Hemophilia is an inherited bleeding, or coagulation, disorder. Children with hemophilia lack the ability to stop bleeding because of the low levels, or complete absence, of specific proteins, called "factors," in their blood that are necessary for clotting. Proper clotting of blood helps prevent excessive bleeding.
In the US, there are about 18,000 people with hemophilia.
There are many factors in the blood that are involved in the function of forming clots to stop bleeding. A child with hemophilia is missing, or has a low supply of, one of the factors needed in order for the blood to clot. Two factors that affect blood clotting are factor VIII and factor IX. Hemophilia is classified by its level of severity. Hemophilia may be mild, moderate, or severe, depending upon the level of the blood clotting factors in the blood.
The three main forms of hemophilia include the following:
- hemophilia A - caused by a lack of the blood clotting factor VIII; approximately 85 percent of hemophiliacs have type A disease.
- hemophilia B - caused by a deficiency of factor IX.
- von Willebrand disease - a part of the factor VIII molecule known as von Willebrand factor or ristocetin cofactor is reduced. The von Willebrand factor involves helping the platelets (blood cells that control bleeding) attach to the lining of a vein or artery. This missing factor results in prolonged bleeding time because the platelets are unable to attach to the wall of the vessel and form a plug to stop the bleeding.
Hemophilia types A and B are inherited diseases passed on from a gene located on the X chromosome. Females have two X chromosomes, while males have one X and one Y chromosome. A female carrier of hemophilia has the hemophilia gene on one of her X chromosomes, and there is a 50 percent chance that she may pass the defective gene to her male offspring.
- Males who inherit the defective gene will develop hemophilia. Males with hemophilia do not pass the gene to their sons; however, they do pass the gene to their daughters.
- Females who inherit the defective gene will become carriers who may, in turn, have a 50 percent chance of passing it on to their children. Although females who inherit the gene generally have no active problems related to hemophilia, some may have other problems associated with bleeding, such as excessive menstrual bleeding, frequent or severe nosebleeds, or bleeding after dental procedures or surgery.
In about one-third of hemophilia cases, there is no family history of the disease. These cases are due to a new or spontaneous development of the defective gene in the female.
The most common symptom of hemophilia is excessive, uncontrollable bleeding because of the missing or low-level clotting factor in the blood. Bleeding may occur even when there is no injury. It most often occurs in the joints and in the head.
The following are the other most common symptoms of hemophilia. However, each individual may experience symptoms differently. Symptoms may include:
Bruises can occur from small accidents, which can result in a large hematoma (a collection of blood under the skin causing swelling).
- bleeds easily
A tendency to bleed from the nose, mouth, and gums with minor trauma, teeth brushing, and/or dental work is often an indication of hemophilia.
- bleeding into a joint
Hemarthrosis (bleeding into a joint) can cause pain, immobility, and eventually deformity if not medically managed properly. This is the most common site of complications due to hemophilia bleeding. These joint bleeds can lead to chronic, painful, arthritis, deformity, and crippling with repeated occurrences.
- bleeding into the muscles
Bleeding into the muscles can cause swelling, pain, and redness. Swelling from excessive blood in these areas can cause increased pressure on tissues and nerves in the area, resulting in permanent damage and/or deformity.
- bleeding from injury or bleeding in the brain
Bleeding from injury, or spontaneously in the brain, is the most common cause of death in children with hemophilia and the most serious bleeding complication.
- other sources of bleeding
Blood found in the urine or stool may also be a symptom of hemophilia.
The symptoms of hemophilia may resemble other Hematology & Blood Disorders or medical problems. Always consult your physician for a diagnosis.
In addition to a complete medical history and physical examination, your physician may perform numerous blood tests including clotting factor levels, a complete blood count (CBC), assessment of bleeding times, and/or DNA (deoxyribonucleic acid) testing.
The most common cause of disability from hemophilia is chronic joint disease, or arthropathy, which is caused by uncontrolled bleeding into the joints.
Hemorrhage, which is a severe internal or external discharge of blood, is a continuing problem.
Specific treatment for hemophilia will be determined by your physician based on:
- your age, overall health, and medical history
- extent of the disease
- type and severity of hemophilia
- your tolerance for specific medications, procedures, or therapies
- expectations for the course of the disease
- your opinion or preference
Treatment may include:
- blood transfusions
- prophylactic (preventive) treatment with infused clotting factors
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