Hemophilia

Hemophilia is an inherited disorder in which a person's blood lacks a certain protein important in forming blood clots, leading to excessive bleeding.

A woman suffering from hemophilia

What Is- Hemophilia

Hemophilia (heem-o-FILL-ee-ah) is a rare bleeding disorder in which the blood doesn't clot normally.

If you have hemophilia, you may bleed for a longer time than others after an injury. You also may bleed inside your body (internally), especially in your knees, ankles, and elbows. This bleeding can damage your organs and tissues and may be life threatening.

Overview

Hemophilia usually is inherited. "Inherited” means that the disorder is passed from parents to children through genes. People born with hemophilia have little or no clotting factor. Clotting factor is a protein needed for normal blood clotting. There are several types of clotting factors. These proteins work with platelets (PLATE-lets) to help the blood clot. Platelets are small blood cell fragments that form in the bone marrow—a sponge-like tissue in the bones. Platelets play a major role in blood clotting. When blood vessels are injured, clotting factors help platelets stick together to plug cuts and breaks on the vessels and stop bleeding.

Types

The two main types of hemophilia are A and B.

• If you have hemophilia A, you're missing or have low levels of clotting factor VIII (8). About 8 out of 10 people who have hemophilia have type A. If you have hemophilia B, you're missing or have low levels of clotting factor IX (9).
• Rarely, hemophilia can be acquired. "Acquired” means you aren't born with the disorder, but you develop it during your lifetime. This can happen if your body forms antibodies (proteins) that attack the clotting factors in your bloodstream. The antibodies can prevent the clotting factors from working.

Inherited hemophilia

Pet scan on hemophilia and aids patient

Prognosis

• Hemophilia can be mild, moderate, or severe, depending on how much clotting factor is in your blood. About 7 out of 10 people who have hemophilia A have the severe form of the disorder.
• People who don't have hemophilia have a factor VIII activity of 100 percent. People who have severe hemophilia A have a factor VIII activity of less than 1 percent.
• Hemophilia usually occurs in males (with rare exceptions). About 1 in 5,000 males are born with hemophilia each year.

Hemophilia A

• Classic hemophilia
• Factor VIII deficiency

Hemophilia B

• Christmas disease
• Factor IX deficiency

Causes- Hemophilia

• A defect in one of the genes that determines how the body makes blood clotting factor VIII or IX causes hemophilia.
• These genes are located on the X chromosomes (KRO-muh-somz).
• Chromosomes come in pairs. Females have two X chromosomes, while males have one X and one Y chromosome.
• Only the X chromosome carries the genes related to clotting factors.
• A male who has a hemophilia gene on his X chromosome will have hemophilia.
• When a female has a hemophilia gene on only one of her X chromosomes, she is a "hemophilia carrier” and can pass the gene to her children. Sometimes carriers have low levels of clotting factor and have symptoms of hemophilia, including bleeding.
• Clotting factors are proteins in the blood that work together with platelets to stop or control bleeding.
• Very rarely, a girl may be born with a very low clotting factor level and have a greater risk for bleeding, similar to boys who have hemophilia and very low levels of clotting factor.
• There are several hereditary and genetic causes of this much rarer form of hemophilia in females.
• Some males who have the disorder are born to mothers who aren't carriers.
• In these cases, a mutation (random change) occurs in the gene as it is passed to the child.

Hemofilia inheritance

Signs, Symptoms, and Complications- Hemophilia

The major signs and symptoms of hemophilia are excessive bleeding and easy bruising.

Excessive Bleeding

The extent of bleeding depends on how severe the hemophilia is. Children who have mild hemophilia may not have signs unless they have excessive bleeding from a dental procedure, an accident, or surgery. Males who have severe hemophilia may bleed heavily after circumcision. Bleeding can occur on the body's surface (external bleeding) or inside the body (internal bleeding).

Signs of external bleeding may include:

• Bleeding in the mouth from a cut or bite or from cutting or losing a tooth
• Nosebleeds for no obvious reason
• Heavy bleeding from a minor cut
• Bleeding from a cut that resumes after stopping for a short time

Signs of internal bleeding may include:

• Blood in the urine (from bleeding in the kidneys or bladder)
• Blood in the stool (from bleeding in the intestines or stomach)
• Large bruises (from bleeding into the large muscles of the body)

Bleeding in the Joints

• Bleeding in the knees, elbows, or other joints is another common form of internal bleeding in people who have hemophilia.
• This bleeding can occur without obvious injury.
• At first, the bleeding causes tightness in the joint with no real pain or any visible signs of bleeding.
• The joint then becomes swollen, hot to touch, and painful to bend.
• Swelling continues as bleeding continues.
• Eventually, movement in the joint is temporarily lost.
• Pain can be severe.
• Joint bleeding that isn't treated quickly can damage the joint.

Bleeding in the Brain

Internal bleeding in the brain is a very serious complication of hemophilia. It can happen after a simple bump on the head or a more serious injury. The signs and symptoms of bleeding in the brain include:

• Long-lasting, painful headaches or neck pain or stiffness
• Repeated vomiting
• Sleepiness or changes in behavior
• Sudden weakness or clumsiness of the arms or legs or problems walking
• Double vision
• Convulsions or seizures

Diagnosis- Hemophilia

If you or your child appears to have a bleeding problem, your doctor will ask about your personal and family medical histories. This will reveal whether you or your family members, including women and girls, have bleeding problems. However, some people who have hemophilia have no recent family history of the disease. You or your child also will likely have a physical exam and blood tests to diagnose hemophilia. Blood tests are used to find out:

• How long it takes for your blood to clot
• Whether your blood has low levels of any clotting factors
• Whether any clotting factors are completely missing from your blood

The test results will show whether you have hemophilia, what type of hemophilia you have, and how severe it is.

Hemophilia A and B are classified as mild, moderate, or severe, depending on the amount of clotting factor VIII or IX in the blood.

Mild hemophilia	5–40 percent of normal clotting factor
Moderate hemophilia	1–5 percent of normal clotting factor
Severe hemophilia	Less than 1 percent of normal clotting factor

• The severity of symptoms can overlap between the categories.
• For example, some people who have mild hemophilia may have bleeding problems almost as often or as severe as some people who have moderate hemophilia.
• Severe hemophilia can cause serious bleeding problems in babies.
• Thus, children who have severe hemophilia usually are diagnosed during the first year of life.
• People who have milder forms of hemophilia may not be diagnosed until they're adults.
• The bleeding problems of hemophilia A and hemophilia B are the same.
• Only special blood tests can tell which type of the disorder you or your child has.
• Knowing which type is important because the treatments are different.
• Pregnant women who are known hemophilia carriers can have the disorder diagnosed in their unborn babies as early as 12 weeks into their pregnancies.
• Women who are hemophilia carriers also can have "preimplantation diagnosis" to have children who don't have hemophilia.
• For this process, women have their eggs removed and fertilized by sperm in a laboratory.
• The embryos are then tested for hemophilia. Only embryos without the disorder are implanted in the womb.

Treatment With Replacement Therapy

• The main treatment for hemophilia is called replacement therapy.
• Concentrates of clotting factor VIII (for hemophilia A) or clotting factor IX (for hemophilia B) are slowly dripped or injected into a vein. These infusions help replace the clotting factor that's missing or low.
• Clotting factor concentrates can be made from human blood. The blood is treated to prevent the spread of diseases, such as hepatitis.
• With the current methods of screening and treating donated blood, the risk of getting an infectious disease from human clotting factors is very small.
• To further reduce the risk, you or your child can take clotting factor concentrates that aren't made from human blood. These are called recombinant clotting factors.
• Clotting factors are easy to store, mix, and use at home—it only takes about 15 minutes to receive the factor.
• You may have replacement therapy on a regular basis to prevent bleeding.
• This is called preventive or prophylactic (PRO-fih-lac-tik) therapy.
• Or, you may only need replacement therapy to stop bleeding when it occurs. This use of the treatment, on an as-needed basis, is called demand therapy.
• Demand therapy is less intensive and expensive than preventive therapy.
• However, there's a risk that bleeding will cause damage before you receive the demand therapy.

Complications of Replacement Therapy

Complications of replacement therapy include:

• Developing antibodies (proteins) that attack the clotting factor
• Developing viral infections from human clotting factors
• Damage to joints, muscles, or other parts of the body resulting from delays in treatment

• Antibodies to the clotting factor.
• Antibodies can destroy the clotting factor before it has a chance to work.
• This is a very serious problem.
• It prevents the main treatment for hemophilia (replacement therapy) from working.
• These antibodies, also called inhibitors, develop in about 20–30 percent of people who have severe hemophilia A.
• Inhibitors develop in 2–5 percent of people who have hemophilia B.
• When antibodies develop, doctors may use larger doses of clotting factor or try different clotting factor sources.
• Sometimes the antibodies go away.
• Researchers are studying new ways to deal with antibodies to clotting factors.

• Viruses from human clotting factors.
• Clotting factors made from human blood can carry the viruses that cause HIV/AIDS and hepatitis.
• However, the risk of getting an infectious disease from human clotting factors is very small due to:

• Careful screening of blood donors
• Testing of donated blood products
• Treating donated blood products with a detergent and heat to destroy viruses
• Vaccinating people who have hemophilia for hepatitis A and B

Damage to joints, muscles, and other parts of the body. Delays in treatment can cause damage such as:  

• Bleeding into a joint. If this happens many times, it can lead to changes in the shape of the joint and impair the joint's function.
• Swelling of the membrane around a joint.
• Pain, swelling, and redness of a joint.
• Pressure on a joint from swelling, which can destroy the joint.

Home Treatment With Replacement Therapy

You can do both preventive (ongoing) and demand (as-needed) replacement therapy at home.

Many people learn to do the infusions at home for their child or for themselves. Home treatment has several advantages:

• You or your child can get quicker treatment when bleeding happens. Early treatment lowers the risk of complications.
• Fewer visits to the doctor or emergency room are needed.
• Home treatment costs less than treatment in a medical care setting.
• Home treatment helps children accept treatment and take responsibility for their own health.

Discuss options for home treatment with your doctor or your child's doctor. A doctor or other health care provider can teach you the steps and safety procedures for home treatment. Hemophilia treatment centers are another good resource for learning about home treatment (discussed in "Living With Hemophilia”).

Other Types of Treatment

Desmopressin

• Desmopressin (DDAVP) is a man-made hormone used to treat people who have mild hemophilia A.
• DDAVP isn't used to treat hemophilia B or severe hemophilia A.
• DDAVP stimulates the release of stored factor VIII and von Willebrand factor; it also increases the level of these proteins in your blood.
• Von Willebrand factor carries and binds factor VIII, which can then stay in the bloodstream longer.
• DDAVP usually is given by injection or as nasal spray.
• Because the effect of this medicine wears off if it's used often, the medicine is given only in certain situations.
• For example, you may take this medicine prior to dental work or before playing certain sports to prevent or reduce bleeding.

Antifibrinolytic Medicines

• Antifibrinolytic medicines (including tranexamic acid and epsilon aminocaproic acid) may be used with replacement therapy.
• They're usually given as a pill, and they help keep blood clots from breaking down.
• These medicines most often are used before dental work or to treat bleeding from the mouth or nose or mild intestinal bleeding.

Gene Therapy

Researchers are trying to find ways to correct the faulty genes that cause hemophilia. Gene therapy hasn't yet developed to the point that it's an accepted treatment for hemophilia. However, researchers continue to test gene therapy in clinical trials.

Treatment of a Specific Bleeding Site

Pain medicines, steroids, and physical therapy may be used to reduce pain and swelling in an affected joint. Talk with your doctor or pharmacist about which medicines are safe for you to take.

Which Treatment Is Best for You?

The type of treatment you or your child receives depends on several things, including how severe the hemophilia is, the activities you'll be doing, and the dental or medical procedures you'll be having.

• Mild hemophilia—Replacement therapy usually isn't needed for mild hemophilia. Sometimes, though, DDAVP is given to raise the body's level of factor VIII.
• Moderate hemophilia—You may need replacement therapy only when bleeding occurs or to prevent bleeding that could occur when doing certain activities. Your doctor also may recommend DDAVP prior to having a procedure or doing an activity that increases the risk of bleeding.

Severe hemophilia—You usually need replacement therapy to prevent bleeding that could damage your joints, muscles, or other parts of your body. Typically, replacement therapy is given at home two or three times a week.

• This preventive therapy usually is started in patients at a young age and may need to continue for life.
• For both types of hemophilia, getting quick treatment for bleeding is important.
• Quick treatment can limit damage to your body. If you or your child has hemophilia, learn to recognize signs of bleeding.
• Other family members also should learn to watch for signs of bleeding in a child who has hemophilia.
• Children sometimes ignore signs of bleeding because they want to avoid the discomfort of treatment.

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