Summer BanksHemophilia
December 12th 2006 04:29
Hemophilia :
Hemophilia is a sex-linked hereditary bleeding disorder in which the clotting mechanism of the blood does not function properly. Blood normally contains several factors that enable clotting to occur. These are designated coagulation factors I through XIII. In the most common form of hemophilia -- classic hemophilia, or hemophilia A -- factor VIII is deficient. In this case, factors I through VII function adequately, but the clotting process is interrupted by a lack of sufficient amounts of factor VIII. Hemophilia B is the other common form of hemophilia, although it occurs significantly less often than hemophilia A. Hemophilia B is caused by a deficiency of factor IX. Hemophilia B is also known as Christmas disease.
Cause :
Hemophilia is inherited as a sex-linked recessive trait -- a woman can pass on the defective gene for the trait without being affected herself. The gene that causes the disorder appears on the X chromosome, which is the female sex chromosome. (Men have one X chromosome and one Y chromosome, whereas women have two X chromosomes.) If a woman has one defective X chromosome, the presence of her other, normal X chromosome ensures that she will not suffer from the disease herself. However, she can pass on her defective X chromosome to her sons, who will have the disease because they do not have a normal X chromosome to counteract the
defect.
If she passes the defective chromosome to her daughters, they, too, will be carriers but will not have the disease. A male hemophiliac passes his defective X chromosome to his daughters, making them carriers. However, he passes on only his normal Y chromosome to his sons, who therefore will not have the disease (unless their mother is a carrier). Although the condition appears almost exclusively in men, a woman can be a hemophiliac if her mother is a carrier and her father is a hemophiliac (in such a case, she inherits two defective X chromosomes).
Symptoms :
Although affected individuals are born with the disease, the onset of symptoms is variable. Milder cases may not be readily apparent. The symptoms of hemophilia usually become evident during early childhood. When a cut in the skin occurs or an injury is suffered, the bleeding may be substantial and prolonged. In severe cases, spontaneous internal bleeding may occur without any obvious cause. Blood may appear in the urine due to internal bleeding. Pain is also a symptom when the bleeding occurs internally, between muscles and into joints. The course of the disease may result in irreversible damage to the joints, which, in turn, results in greater pain and in limitation of movement.
Diagnosis :
If a child has any of the symptoms of hemophilia, or if there is a family history of hemophilia, a physician should be consulted. The physician will order laboratory tests to establish the diagnosis. The most common test for hemophilia is determination of the partial thromboplastin time (PTT), which indicates how long it takes for the blood to clot. Additional laboratory tests, including direct measurement of clotting factors, may be ordered in certain cases.
Treatment :
Treatment of hemophilia has recently undergone dramatic changes. An important breakthrough has been the development of factor VIII replacement therapy. One therapy, cryoprecipitate, is prepared from donated blood plasma (the fluid portion of blood, which contains more factor VIII than whole blood does). The plasma of an individual donor is quickly frozen by a special process and then slowly thawed, so that the portion rich in factor VIII can be separated out. This portion can then be prepared later for intravenous administration. Cryoprecipitate has the disadvantage of having to be stored and prepared in a hospital. Also, since cryoprecipitate is produced from the plasma of a single donor, the amount of factor VIII present in a given preparation is variable.
Treatment of hemophilia A has been further advanced by the development of a process of rapid freezing and dehydration (removal of water) of plasma, called lyophilization. Freeze-dried concentrates are prepared and packaged so that they can be readily dissolved by a simple mixing procedure. (This process is similar in concept to the preparation and use of freeze-dried coffee.) This concentrate, which quickly stops bleeding, is particularly efficient for home use in comparison with cryoprecipitate therapy.
Treatment of hemophilia B involves the use of fresh or stored plasma. Concentrate is also available for hemophilia B and is known as prothrombin complex concentrate.
Prevention :
There are no preventive measures for hemophilia. Genetic testing can now identify carriers of hemophilia with considerable accuracy, however.
Hemophilia is a sex-linked hereditary bleeding disorder in which the clotting mechanism of the blood does not function properly. Blood normally contains several factors that enable clotting to occur. These are designated coagulation factors I through XIII. In the most common form of hemophilia -- classic hemophilia, or hemophilia A -- factor VIII is deficient. In this case, factors I through VII function adequately, but the clotting process is interrupted by a lack of sufficient amounts of factor VIII. Hemophilia B is the other common form of hemophilia, although it occurs significantly less often than hemophilia A. Hemophilia B is caused by a deficiency of factor IX. Hemophilia B is also known as Christmas disease.
Cause :
Hemophilia is inherited as a sex-linked recessive trait -- a woman can pass on the defective gene for the trait without being affected herself. The gene that causes the disorder appears on the X chromosome, which is the female sex chromosome. (Men have one X chromosome and one Y chromosome, whereas women have two X chromosomes.) If a woman has one defective X chromosome, the presence of her other, normal X chromosome ensures that she will not suffer from the disease herself. However, she can pass on her defective X chromosome to her sons, who will have the disease because they do not have a normal X chromosome to counteract the
defect.
If she passes the defective chromosome to her daughters, they, too, will be carriers but will not have the disease. A male hemophiliac passes his defective X chromosome to his daughters, making them carriers. However, he passes on only his normal Y chromosome to his sons, who therefore will not have the disease (unless their mother is a carrier). Although the condition appears almost exclusively in men, a woman can be a hemophiliac if her mother is a carrier and her father is a hemophiliac (in such a case, she inherits two defective X chromosomes).
Symptoms :
Although affected individuals are born with the disease, the onset of symptoms is variable. Milder cases may not be readily apparent. The symptoms of hemophilia usually become evident during early childhood. When a cut in the skin occurs or an injury is suffered, the bleeding may be substantial and prolonged. In severe cases, spontaneous internal bleeding may occur without any obvious cause. Blood may appear in the urine due to internal bleeding. Pain is also a symptom when the bleeding occurs internally, between muscles and into joints. The course of the disease may result in irreversible damage to the joints, which, in turn, results in greater pain and in limitation of movement.
Diagnosis :
If a child has any of the symptoms of hemophilia, or if there is a family history of hemophilia, a physician should be consulted. The physician will order laboratory tests to establish the diagnosis. The most common test for hemophilia is determination of the partial thromboplastin time (PTT), which indicates how long it takes for the blood to clot. Additional laboratory tests, including direct measurement of clotting factors, may be ordered in certain cases.
Treatment :
Treatment of hemophilia has recently undergone dramatic changes. An important breakthrough has been the development of factor VIII replacement therapy. One therapy, cryoprecipitate, is prepared from donated blood plasma (the fluid portion of blood, which contains more factor VIII than whole blood does). The plasma of an individual donor is quickly frozen by a special process and then slowly thawed, so that the portion rich in factor VIII can be separated out. This portion can then be prepared later for intravenous administration. Cryoprecipitate has the disadvantage of having to be stored and prepared in a hospital. Also, since cryoprecipitate is produced from the plasma of a single donor, the amount of factor VIII present in a given preparation is variable.
Treatment of hemophilia A has been further advanced by the development of a process of rapid freezing and dehydration (removal of water) of plasma, called lyophilization. Freeze-dried concentrates are prepared and packaged so that they can be readily dissolved by a simple mixing procedure. (This process is similar in concept to the preparation and use of freeze-dried coffee.) This concentrate, which quickly stops bleeding, is particularly efficient for home use in comparison with cryoprecipitate therapy.
Treatment of hemophilia B involves the use of fresh or stored plasma. Concentrate is also available for hemophilia B and is known as prothrombin complex concentrate.
Prevention :
There are no preventive measures for hemophilia. Genetic testing can now identify carriers of hemophilia with considerable accuracy, however.
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Comment by Jessicca
Learning Something Everyday
Malaysia Found
So if a person who suffers hemopillia must be very careful not to work his / her body to be diabetic or else it would have gone worse.