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What is hemophilia? Hemophilia is a bleeding disorder that slows the blood clotting process. People with this condition often experience prolonged bleeding or oozing following an injury, surgery, or having a tooth pulled. In severe cases of hemophilia, heavy bleeding occurs after minor trauma or even in the absence of injury (spontaneous bleeding). Serious complications can result from bleeding into the joints, muscles, brain, or other internal organs. Milder forms of hemophilia do not involve spontaneous bleeding, and the condition may only become apparent when abnormal bleeding occurs following surgery or a serious injury. The major types of this condition are hemophilia A (also known as classic hemophilia) and hemophilia B (also known as Christmas disease). Although the two types have very similar signs and symptoms, they are caused by mutations in different genes. People with an unusual form of hemophilia B, known as hemophilia B Leyden, experience episodes of excessive bleeding in childhood, but have few bleeding problems after puberty. Another form of the disorder, acquired hemophilia, is not caused by inherited gene mutations. This rare condition is characterized by abnormal bleeding into the skin, muscles, or other soft tissues, usually beginning in adulthood. How common is hemophilia? The two major forms of hemophilia occur much more commonly in males than in females. Hemophilia A is the most common type of the condition; about 1 in 4,000 males worldwide are born with this disorder. Hemophilia B occurs in approximately 1 in 20,000 newborn males worldwide. What genes are related to hemophilia? Mutations in the F8 and F9 genes cause hemophilia. Changes in the F8 gene are responsible for hemophilia A, while mutations in the F9 gene cause hemophilia B. The F8 gene provides instructions for making a protein called coagulation factor VIII. A related protein, coagulation factor IX, is produced from the F9 gene. Coagulation factors are proteins that work together in the clotting process. After an injury, blood clots protect the body by sealing off damaged blood vessels and preventing further blood loss. Mutations in the F8 or F9 gene lead to the production of an abnormal version of coagulation factor VIII or coagulation factor IX. The altered protein cannot participate effectively in the blood clotting process and, in some cases, the protein does not work at all. A shortage of either protein prevents clots from forming properly in response to injury. These problems with blood clotting lead to excessive bleeding that can be difficult to control. Some mutations almost completely eliminate the activity of coagulation factor VIII or coagulation factor IX, resulting in severe hemophilia. Other mutations reduce but do not eliminate the activity of one of these proteins, which usually causes mild or moderate hemophilia. The other, rare form of this condition, acquired hemophilia, results when the body makes specialized proteins called autoantibodies that attack and disable coagulation factor VIII. The production of autoantibodies is sometimes associated with pregnancy, immune system disorders, cancer, or allergic reactions to certain drugs. In about half of cases, the cause of acquired hemophilia is unknown. Read more about the F8 and F9 genes. How do people inherit hemophilia? Hemophilia A and hemophilia B are inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, 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 must be present in both copies of the gene to cause the disorder. Males are affected by X-linked recessive disorders much more frequently than females. A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In X-linked recessive inheritance, a female with one altered copy of the gene in each cell is called a carrier. She can pass on the altered gene to her children, but usually does not experience signs and symptoms of the disorder. In about 10 percent of cases, however, females who carry one altered copy of the F8 or F9 gene will experience mild problems with bleeding. Where can I find information about treatment for hemophilia? These resources address the management of hemophilia and may include treatment providers. Gene Review: Hemophilia A Gene Review: Hemophilia B Genetic Alliance MedlinePlus Encyclopedia: Hemophilia A MedlinePlus Encyclopedia: Hemophilia B You might also find information on treatment of hemophilia in Educational resources and Patient support. Where can I find additional information about hemophilia? You may find the following resources about hemophilia helpful. These materials are written for the general public. MedlinePlus - Health information (3 links) Additional NIH Resources - National Institutes of Health (3 links) Educational resources - Information pages (16 links) Patient support - For patients and families (7 links) You may also be interested in these resources, which are designed for healthcare professionals and researchers. Gene Reviews - Clinical summary (2 links) Gene Tests - DNA tests ordered by healthcare professionals (2 links) Genetic Tools ClinicalTrials.gov PubMed Online Books - Medical and science texts (2 links) OMIM - Genetic disorder catalog (2 links) - Teaching cases - Linking patients to medical research - Recent literature What other names do people use for hemophilia? Hemophilia, familial Hemophilia, hereditary See How are genetic conditions and genes named? in the Handbook. What if I still have specific questions about hemophilia? See How can I find a genetics professional in my area? in the Handbook. Ask the Genetic and Rare Diseases Information Center . Submit your question to Ask the Geneticist . Where can I find general information about genetic conditions? The Handbook provides basic information about genetics in clear language. What does it mean if a disorder seems to run in my family? What are the different ways in which a genetic condition can be inherited? If a genetic disorder runs in my family, what are the chances that my children will have the condition? Why are some genetic conditions more common in particular ethnic groups? These links provide additional genetics resources that may be useful. Genetics and health Resources for Patients and Families Resources for Health Professionals What glossary definitions help with understanding hemophilia? autoantibody ; blood clotting ; blood coagulation ; cancer ; carrier ; cell ; chromosome ; clotting ; coagulation ; coagulation factors ; complication ; deficiency ; familial ; gene ; immune system ; inheritance ; injury ; joint ; mutation ; protein ; puberty ; recessive ; sex chromosomes ; sign ; soft tissue ; spontaneous ; surgery ; symptom ; tissue ; trait ; trauma ; X-linked recessive You may find definitions for these and many other terms in the Genetics Home Reference Glossary. See also Understanding Medical Terminology. References (7 links) The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook. Hemophilia Also called: Christmas disease, Factor IX deficiency, Factor VIII deficiency Hemophilia is a rare inherited disorder in which the blood does not clot normally. About 18,000 people in the U.S. have hemophilia. Each year, about 400 babies are born with the disorder. Hemophilia usually occurs in males (with very rare exceptions). People who have hemophilia may bleed for a long time after an injury or accident. They also may bleed into their knees, ankles and elbows. Bleeding in the joints causes pain and, if not treated, can lead to arthritis. Bleeding in the brain, a very serious complication of hemophilia, requires emergency treatment. The main treatment is injecting the missing clotting factor into the bloodstream. National Heart, Lung, and Blood Institute Start Here Genetics Home Reference: Hemophilia Hemophilia (National Library of Medicine) (National Heart, Lung, and Blood Institute) Basics Overviews Diagnosis/Symptoms Learn More Research Disease Management Reference Shelf Clinical Trials Medical Encyclopedia Genetics Directories Journal Articles Organizations Overviews o Multimedia & Cool Tools Tutorials For You Children Teenagers Frequently Asked Questions: Hemophilia(World Federation of Hemophilia) Also available in Spanish o Hemophilia(Mayo Foundation for Medical Education and Research) o Hemophilia in Pictures(World Federation of Hemophilia) - PDF Also available in Spanish o Learning about Hemophilia Institute) (National Human Genome Research Diagnosis/Symptoms o Coagulation Factors(American Association for Clinical Chemistry) o Fibrinogen(American Association for Clinical Chemistry) o PT and INR (Prothrombin Time, International Normalized Ratio)(American Association for Clinical Chemistry) o PTT(American Association for Clinical Chemistry) Disease Management o JAMA Patient Page: Blood Transfusion(American Medical Association) Also available in Spanish Tutorials o What Is Hemophilia?(Dolan DNA Learning Center) Return to top Clinical Trials o ClinicalTrials.gov: Blood Coagulation Disorders Health) o ClinicalTrials.gov: Hemophilia A (National Institutes of (National Institutes of Health) Return to top Genetics o Genetics Home Reference: Hemophilia (National Library of Medicine) Return to top Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine) o Article: Bleeding disorders: when is normal bleeding not normal? o Article: Therapeutic properties and safety of recombinant factor VIII and factor... o Article: Neuraxial techniques in obstetric and non-obstetric patients with common bleeding... o Hemophilia -- see more articles Return to top Medical Encyclopedia o Hemophilia Return to top Directories o Find a Hematologist(American Society of Hematology) o Hemophilia Treatment Centers(Centers for Disease Control and Prevention) Return to top Organizations o National Heart, Lung, and Blood Institute Return to top Children o FDA Licenses Drug to Prevent Joint Damage in Children with Hemophilia A(Food and Drug Administration) o Hemophilia(Nemours Foundation) Also available in Spanish o How to Deal with Hemophilia(Nemours Foundation) Return to top Teenagers o Hemophilia(Nemours Foundation) Also available in Spanish Return to top Hemophilia Hemophilia Overview Hemophilia Causes Hemophilia Symptoms When to Seek Medical Care Exams and Tests Hemophilia Treatment Self-Care at Home Medications Next Steps Outlook Support Groups and Counseling Synonyms and Keywords Authors and Editors Related hemophilia articles: Hemophilia - on WebMD Hemophilia Overview Hemophilia is an inherited bleeding disorder. The blood of someone with hemophilia will not clot normally. Bleeding may occur spontaneously or following injury. Hemophilia occurs in 2 forms, hemophilia A and B. In both forms, a gene is defective. The defective gene interferes with the ability of the body to produce the clotting factors that allow for normal clotting. The result is a tendency for abnormal, excessive bleeding. Hemophilia A occurs in 1 in 10,000 people. Hemophilia B occurs in 1 in 40,000. With either disorder, you may show a mild form in which bleeding occurs only under severe stress, such as major injury. o Moderate cases rarely will have spontaneous bleeding but will bleed after surgery or trauma. o Severe cases will exhibit spontaneous bleeding-that is, bleeding without any recognizable trauma. Spontaneous bleeding can occur in any part of your body, but it is usually in the joints of the fingers, wrists, feet, and spine. Hemophilia (cont.) IN THIS ARTICLE Hemophilia Overview Hemophilia Causes Hemophilia Symptoms When to Seek Medical Care Exams and Tests Hemophilia Treatment Self-Care at Home Medications Next Steps Outlook Support Groups and Counseling Synonyms and Keywords Authors and Editors Hemophilia Causes Men have only one X chromosome. If that chromosome carries the abnormal hemophilia gene, the man will have the disease hemophilia. Both hemophilia A and B are linked to the X chromosome, which means they primarily affect men. Women have two X chromosomes. Even if one of the X chromosomes carries the defective gene, the normal gene on the other X chromosome will protect the woman from hemophilia. The gene does not affect them, but they carry it and pass it on to their children. If a woman is a carrier, she has a 50% chance that her sons will have hemophilia. Likewise, she has a 50% chance that her daughters will be carriers of hemophilia. This assumes that the woman's partner is not a hemophiliac. A man who has hemophilia has a 100% chance that his daughters will be carriers, since they must inherit the defective x chromosome from the father. His sons will not be affected if the mother is not a carrier. The transmission of this gene to offspring accounts for 70% of the cases of hemophilia. The remaining 30% occur from spontaneous changes in genes responsible for causing hemophilia. Hemophilia Symptoms If a toddler has hemophilia, bleeding often results from falls. The bleeding may repeat if the fall disrupts a clot. Blood in the urine (hematuria) commonly occurs with hemophilia. Many people will have microscopic blood in urine, not visible with the naked eye. Gross hematuria, blood you can see in urine, also is very common and may mean a bladder infection. You cannot see bleeding into muscle tissue and joints if you have hemophilia. But you will have pain and may see swelling. Bleeding into a muscle usually follows trauma. Common sites are the thigh, calf, and forearm. Bleeding into joints is the most crippling aspect of hemophilia as well as the most common site. The disease most commonly affects the knee followed by the elbow, ankle, shoulder, and wrist. You may feel a warm prickly sensation before you develop pain and swelling in the joint. The degree of swelling does not match the severity of your bleeding. You may be bleeding significantly but show only a little swelling. Bleeding into a joint not only makes that joint more likely to bleed in the future but also leads to progressive stiffness. This joint, which is now more prone to re-bleeding, is called the target joint. Bleeding into the central nervous system can be life threatening. Usually only severe hemophiliacs exhibit such bleeding, but it may occur in both moderate and mild hemophilia. Bleeding may occur in or around the brain (intracranial) or into the spinal cord (intraspinal), depending on the situation. Injury to your head or spinal column normally causes this bleeding. Your injury may seem minor. Adults are more prone to having intracranial bleeding without injury (spontaneous bleeding), accounting for nearly 50% of the cases. Headache, nausea, vomiting, and seizure often accompany bleeding into the brain. Backache or even paralysis can accompany bleeding into the spinal column. When to Seek Medical Care Call your doctor after any significant physical trauma. Call your doctor also if you cannot control external bleeding with simple pressure. Because you may have internal as well external bleeding, always err on the side of safety and call your doctor. Be particularly concerned about bleeding into your joints or your central nervous system because of long-term complications and the possibility of death. Because hemophilia treatment involves blood products, you often may need to be treated in an emergency department or other health care facility, especially if you have severe hemophilia. Your doctor should evaluate any head or spinal trauma. A severe hemophiliac should be evaluated at a hospital's emergency department for any bleeding whatsoever, because his or her blood will not clot adequately on its own in these situations: Oral bleeding Bleeding from skin that does not stop with simple pressure Bleeding from muscles and joints Any person with hemophilia who has significant trauma anywhere on the body should be evaluated at a hospital regardless of the severity of the disease. Exams and Tests A family history of bleeding disorders aids in diagnosing hemophilia. But certain tests help quantify the disease. Pronounced bruising at childbirth or bleeding with circumcision may suggest a case of severe hemophilia. A moderate case of hemophilia may become apparent during the toddler years when falls are common. A mild case may not become evident until adulthood when you need surgery. Blood tests can be performed if you have any reason to suspect hemophilia. Blood may be checked directly for certain factors. Test results will be low depending on which form of hemophilia you have. In either case, your activated partial thromboplastin time (aPTT), a measurement of the clotting of blood, will be prolonged. Hemophilia Treatment Self-Care at Home Most often people with hemophilia require medical treatment if bleeding or an injury occurs. You can take the following simple actions at home. Avoid aspirin and anti-inflammatory agents such as ibuprofen (Advil) because they may further interfere with blood clotting. If you have blood in your urine, drink plenty of fluids to ensure hydration. Apply direct pressure to any site at which you are bleeding externally. Apply ice and put a splint on affected joints after bleeding to provide relief from symptoms. If you have the training on the disease process, you can give yourself factor replacement therapy. But you should do so under consultation from your doctor. Medications Treatment of hemophilia aims to stop your bleeding. Doctors stop bleeding either by overcoming the deficiency in the clotting factors or by aiding in blood clotting. Giving a medicine called DDAVP (Octostim) may increase levels of Factor VIII (8) temporarily. But the medication will not be effective in severe cases of hemophilia or in hemophilia B. Aminocaproic acid (Amicar) and tranexamic acid (Cyklokapron) assist your clotting by slowing down the ongoing destruction of clots. These medications are useful in oral bleeding in either hemophilia A or B. You may be given an IV infusion of factor. You are given purified Factor VII or IX (9) depending on the type of hemophilia you have. Doctors determine the amount to give you by where your bleeding occurs and how much you weigh. The site of your bleeding also will determine the number of days you must be given the factor. Hemophilia (cont.) IN THIS ARTICLE Hemophilia Overview Hemophilia Causes Hemophilia Symptoms When to Seek Medical Care Exams and Tests Hemophilia Treatment Self-Care at Home Medications Next Steps Outlook Support Groups and Counseling Synonyms and Keywords Authors and Editors Next Steps Outlook With proper medical care, people with hemophilia can expect to live full and productive lives. Yet complications still occur. During the late 1970s through 1985, up to 60% of severe hemophiliacs had contracted the HIV virus (the virus that causes AIDS) from blood products. Because of the development of genetically engineered factor and improved purification processes, no case of HIV transmission from clotting factors has been documented since 1986. Those using blood-derived products are still at risk for getting hepatitis. Hepatitis A can resist some purifying methods, but no hepatitis C transmission has been reported since 1997. Doctors recommend that all people with hemophilia receive the hepatitis B vaccine. Despite current treatments, people with hemophilia still undergo degenerative changes due to bleeding in the joints. When repeated bleeding occurs, chronic swelling results in that joint. The swelling leads to degeneration of cartilage and bone. Ultimately this process will cause chronic joint stiffness and pain. Once babies with hemophilia begin crawling and cruising, parents may notice raised bruises on the stomach, chest, buttocks, and back. Sometimes, because bruises appear in unlikely places, parents may be suspected of child abuse before their child is diagnosed with hemophilia. The baby may also be fussy and may not want to reach for a cup, walk, or crawl. Other symptoms include: prolonged nosebleeds excessive bleeding from biting down on the lips or tongue excessive bleeding following a tooth extraction excessive bleeding following surgery blood in the urine (called hematuria) The most common type of bleeding in hemophilia involves muscles and joints. A child with hemophilia will usually refuse to move the affected joint or muscle because of pain and swelling. Recurrent joint bleeding can also lead to chronic damage. Diagnosis Your doctor may suspect your child has hemophilia if there's a pattern of bruising and bleeding, particularly if this includes bleeding into the joint. Diagnosing the condition requires a set of blood tests, including a complete blood count (CBC), prothrombin time (PT), activated partial thromboplastin time (PTT), factor VIII level, and factor IX level. Treatment Although hemophilia is a lifelong condition with no cure (other than liver transplantation), it can be successfully managed with clotting factor replacement therapy — periodic infusions of the deficient clotting factor into the child's bloodstream. Factor replacement may be given through an intravenous (IV) line either at the hematology clinic or at home by a visiting nurse or by parents (and even older patients) who have undergone special training. Your child's hemophilia team (doctors called hematologists who specialize in treating blood disorders, nurse practitioners, nurses, and social workers) will teach you how to prepare the concentrated clotting factor and when and how to inject it into your child's vein. Once the clotting factor is "infused," it begins to work quickly and helps prevent joint damage. Although these treatments are effective, they are also expensive. According to the National Heart, Lung, and Blood Institute, most kids in the United States who begin receiving regular infusions early in life will exhaust the average lifetime insurance limit of $1,000,000 by their second decade. Between 14% and 25% of children with severe hemophilia A develop inhibitors (antibodies to the clotting factor). Their bodies view the clotting factor as a foreign substance and develop antibodies that block its clotting action. This can make the hemophilia difficult to treat. One method for overcoming the inhibitors is to increase the body's tolerance to the clotting factor by carefully infusing increasing amounts of the clotting factor over time. Inhibitors to factor IX (hemophilia B) are less common and are also more difficult to treat. Also, a new medication called recombinant factor VII has helped many patients with inhibitors. It activates another part of the coagulation process directly and bypasses the deficiencies. Preventing Problems You can help your child with hemophilia prevent problems by encouraging healthy behaviors now. For example, exercise can strengthen muscles and help decrease bleeding from injuries. Swimming is strongly encouraged because it exercises all the muscle groups without putting stress on the joints. Your child's weight should also be managed properly, because excess weight can cause strain in regions of the body. If your child is overweight, speak to your doctor for advice on weight management. Medications can also help prevent problems in kids within hemophilia. Many patients prevent "bleeds" by infusing clotting factors on a regular basis (usually two or three times per week). Some young children have a surgical procedure to implant a central venous catheter (a hollow, soft tube) into a vein. The catheter can be used to give concentrates of clotting factors. Your Child's Needs Although each stage of development comes with its own set of issues, experts say the toddler and teenage years can be the most challenging for kids with hemophilia. Both phases naturally involve a child's quest for independence. For example, a toddler may not tell his or her parents about an injury that resulted from doing something that wasn't allowed (i.e., riding a bike without a helmet, jumping on the furniture, running in the house, etc.). Most kids, though, will discover that seeking prompt treatment is better than waiting until pain and swelling become unbearable. Ask your family members, caregivers, and your child's teachers if they would like to learn more about hemophilia by meeting with your doctor or other members of the hemophilia team. Kids with hemophilia can still participate in activities, though they might have to take on a different role. For example, hemophilia might prevent kids from participating in contact sports but they can still be a part of the team as the scorekeeper or assistant manager. Another excellent option is to send them to an appropriate summer camp where they can meet other kids with hemophilia and work toward being able to give themselves clotting factor replacement therapy for a sense of control over the condition. Ask your child's doctor for information about finding a camp near you. Caring for Kids With Hemophilia When your child is an infant, you should put bumper pads in the crib, cushion furniture with sharp edges, and put gates across stairs to prevent falls. As your baby begins to crawl and walk, special knee and elbow pads can offer protection against joint bleeds. Some parents sew a pocket in the seat of their child's pants and pad it with a piece of diaper. If your house has ceramic tile or hardwood floors, consider installing carpet or buying rugs to soften the floor surface. Depending on how rambunctious and adventurous your toddler is, you might want to have him or her wear a helmet to protect against head injuries. Dental care is just as important for a child with hemophilia, but routine cleanings can sometimes cause bleeding. For this reason, it's important that your child's dentist has experience with hemophilia. This will make it easier for the dentist to respond to any bleeding. Kids with hemophilia can generally sense when a bleed has occurred. They often describe a tingly or bubbly sensation in a joint. It may also feel warm to the touch. Encourage your child to tell you when he or she senses a bleed — a quick infusion is the key to preventing longterm damage. Doctors also recommend splinting an affected joint for a short period of time and then applying ice to decrease inflammation, promote clotting, and relieve pain. Acetaminophen (such as Tylenol) is the preferred pain reliever because many other over-the-counter pain medications contain aspirin or NSAIDs (non-steroidal anti-inflammatory drugs such as ibuprofen or naproxen sodium), which can affect blood platelets and lead to increased bleeding. Bleeds must be treated promptly because prolonged bleeding can cause joint disorders. The accumulation of blood in the joint spaces can erode the smooth surfaces that allow limbs to bend easily. As the surfaces roughen, inflammation and the number of bleeds can increase. This cycle can lead to chronic joint damage that may require surgery to remove the damaged joint tissue (called a synovectomy). When to Call the Doctor Certain bleeds require medical attention, including those injuries affecting: the central nervous system — any suspected trauma to the head, neck, or back the face, including the eyes and ears the throat or another portion of the airway the gastrointestinal tract (which might produce signs such as bright red or black blood in your child's stool) the kidneys and urinary tract (if you find blood in the urine, this may require treatment and bed rest) the iliopsoas muscle in the trunk (which might produce signs that mimic a hip or abdominal bleed, including lower abdominal/groin or upper thigh pain, an inability to raise the leg on the affected side, and a feeling of relief when contracting or flexing that side of the body) the genital area the hips or shoulders (these can be complicated bleeds because they involve the rotator joints) large muscle compartments, such as the thighs If the bleed requires going to the emergency room, make sure your child is treated at a hospital that has experience treating hemophilia. Any injury affecting the brain or any part of the central nervous system or a vital organ should be treated as an emergency and you should get medical assistance immediately. Looking to the Future Tremendous advances have been made in the treatment of hemophilia, and most patients can now lead full, healthy lives with careful management of their condition. The development of clotting factors made in the laboratory has virtually eliminated the danger of transfusion-related infection with HIV or hepatitis viruses from clotting factor replacement therapy. And regular home-based infusions have helped reduce chronic joint problems. In the future, people with hemophilia may have access to continuous infusion of clotting factors under the skin or in pill form. Some doctors are also encouraged by research involving gene therapy. Thanks to advances like these, kids with hemophilia can now participate in a wide range of sports and have the freedom to lead more active lives.