Sarah Moreno Ms.Brown Child dev. -6 Hemophilia Sarah Moreno Ms.Brown Child dev. -6

Definition Hemophilia is a rare bleeding disorder that prevents the blood from clotting properly, so a person who has it bleeds more than someone without hemophilia does. It's a genetic disorder, which means it's the result of a change in genes that was either inherited (passed on from parent to child) or occurred during development in the womb. Hemophilia A and B are both caused by a genetic defect present on the X chromosome. (Hemophilia C is inherited in a different fashion.) About 70 percent of all people with hemophilia A or B inherited the disease. The other 30 percent develop from a spontaneous genetic mutation.

What is the difference between hemophilia A and hemophilia B? The most common type of hemophilia is called hemophilia A. This means the person does not have enough clotting factor eight. A less common type is hemophilia B. This person does not have enough clotting factor nine. The result is the same for people with hemophilia A and B they both bleed for a longer time than normal. It is MOST common in males type A- 1 in 4,000 type B- 1 in 40,000

What happens to us? When cut, the body naturally protects itself. Sticky blood cells called platelets go to where the bleeding is and plug up the hole. This is the first step in the clotting process. When the platelets plug the hole, they release chemicals that attract more sticky platelets and also activate various proteins in the blood known as clotting factors. These proteins mix with the platelets to form fibers, and these fibers make the clot stronger and stop the bleeding.

What happens to them? In hemophilia, blood does not clot properly. After bleeding starts, it takes longer for bleeding to stop than in a person who has blood that clots normally. A bleeding episode often begins with an injury. Minor injuries may not always cause excessive bleeding. More severe injuries, or injuries in the mouth, more often cause excessive bleeding and frequently require emergency care.

What causes the genetic disorder? Hemophilia A and hemophilia B are inherited in an X-linked recessive pattern. The genes associated with these conditions are located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, it is very rare for females to have hemophilia. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

Hemophilia is a recessive disorder. Various diagnostic tests are available to measure, under carefully controlled conditions, the length of time it takes to produce certain components of the final fibrin clot. The activated partial thromboplastin time (APTT) is performed and will typically be prolonged while a prothrombin time (PT) will likely be normal.

Signs and Symptoms Common symptoms Many large or deep bruises Joint pain and swelling caused by internal bleeding Unexplained and excessive bleeding or bruising Blood in your urine or stool Prolonged bleeding from cuts or injuries or after surgery or tooth extraction Nosebleeds without a known cause Tightness in your joints In infants, unexplained irritability Unusual bleeding after immunizations Emergency signs Sudden pain, swelling, and warmth of large joints, such as knees, elbows, hips and shoulders, and of the muscles of your arms and legs Bleeding from an injury, especially if you have a severe form of hemophilia Painful, lasting headache Repeated vomiting Extreme fatigue Neck pain Double vision

The only way to detect hemophilia is through a blood test to measure the clotting factor level. If hemophilia is known to run in a family, newborn babies should be tested. You can test for hemophilia A and B when a baby is born. The blood can be drawn from the umbilical cord. However, the factor IX level in a newborn baby is lower than it will be later in life. Repeating the test at 6 to 12 months of age can show the factor IX level a person can expect to have the rest of his life. At the birth of a baby who may have hemophilia A, it is possible to test for the disorder using blood from the umbilical cord. You have to wait to test for hemophilia B. The hemophilia B test may not be accurate until the baby is six months old.

Treatment Hemophilia treatment varies depending on the severity of the condition: Mild hemophilia A. Treatment may involve slow injection of the hormone desmopressin (DDAVP) into a vein to stimulate a release of more clotting factor to stop bleeding. Occasionally, desmopressin is given as a nasal medication. Moderate to severe hemophilia A or hemophilia B. Bleeding may stop only after an infusion of clotting factor derived from donated human blood or from genetically engineered products called recombinant clotting factors. Repeated infusions may be needed if internal bleeding is serious. Hemophilia C. The clotting factor missing in this type of hemophilia (factor XI) is available only in Europe. In the U.S., plasma infusions are needed to stop bleeding episodes.

COUNSELING People with hemophilia may feel they need help understanding genetics and the impact a genetic disorder like hemophilia can have on life. That's where genetic counselors can be so valuable. Many couples concerned about hemophilia get counseling prior to starting a family.

Is hemophilia lifelong? A person born with hemophilia will have it for life. The level of factor 8 or factor 9 in the blood usually stays the same throughout the person’s life.

While there's no cure for hemophilia, most people with the disease can lead fairly normal lives.