Hemophilia

Hemophilia is an inherited bleeding disorder in which the blood does not clot properly. It happens when the blood does not have enough clotting factor — a protein that controls bleeding. Hemophilia is rare and affects mostly males; severe hemophilia in females is very rare.

Hemophilia is a lifelong condition. It cannot be cured, but with current clotting-factor treatments it can be managed effectively. Internal bleeding episodes, or “bleeds,” are the main problem for most people with hemophilia.

Bleeds#

Bleeds are most commonly into joints or muscles. They can happen without an obvious cause, or as a result of injury. Over time, repeated bleeding into joints and muscles can cause permanent damage, such as arthritis in the joints, and chronic pain.

What causes hemophilia?#

Hemophilia is inherited and runs in families. It is caused by a genetic variation (change) in one of two genes that make blood clotting factor:

• A change in the F8 gene, which makes clotting factor VIII (8), causes hemophilia A.
• A change in the F9 gene, which makes clotting factor IX (9), causes hemophilia B.

These genes sit on the X chromosome, one of the two sex chromosomes (X and Y). Hemophilia is inherited in an X-linked recessive pattern:

• Males (XY) have only one X chromosome, so a single copy of the genetic change is enough to cause the condition.
• Females (XX) have two X chromosomes. A female with a changed F8 or F9 gene usually has another, unchanged copy, and one normal copy is often enough to control bleeding.

A man who has hemophilia will pass the genetic change to his daughters but not his sons. These daughters are said to “carry” the change, and may or may not have symptoms. A woman who carries the change may pass it to her sons and daughters: at each birth there is a 50 per cent chance a son will have hemophilia, and a 50 per cent chance a daughter will carry the gene. Daughters with the change may or may not have symptoms.

In about one third of people born with hemophilia, there is no family history. This happens when a genetic change occurs randomly during reproduction and is passed on at conception. Once hemophilia appears in a family, the change is then passed on following the usual inheritance pattern.

If your child has been diagnosed, it may help to speak to a genetic counselor. As well as providing emotional support, they can explain what causes hemophilia, how it is inherited, and what a diagnosis means for your child and your family. Genetic counselors are trained to give information and support that is sensitive to your circumstances, culture and beliefs.

Types of hemophilia#

There are two major types, which have the same symptoms:

• Hemophilia A is the most common form and is caused by reduced levels of clotting factor VIII (8), due to a change in the F8 gene.
• Hemophilia B, also known as Christmas disease, is caused by reduced levels of clotting factor IX (9), due to a change in the F9 gene.

Levels of severity#

There are three levels of severity — mild, moderate and severe — depending on the amount of clotting factor in the blood. The normal range of factor VIII and factor IX is between 50 and 150 per cent.

• Mild (5–40 per cent of normal): usually only have bleeding problems after dental extractions, surgery, or a bad injury, and might never have a problem.
• Moderate (1–5 per cent of normal): rarely have a bleed for no obvious reason.
• Severe (less than 1 per cent of normal): can have bleeds after surgery, dental work or injuries, including minor bumps and knocks, and may bleed for no obvious reason.

Acquired hemophilia#

Acquired hemophilia is a separate, very rare bleeding disorder that is not inherited. The immune system makes antibodies against one of the body’s own clotting factors, reducing that factor level in the blood. It usually develops in older people and can affect both men and women.

How is hemophilia diagnosed?#

Hemophilia is diagnosed by looking at physical signs of unusual bleeding, checking the family history, and using blood tests to measure clotting-factor levels. Genetic testing can identify the change in the F8 or F9 gene.

Depending on whether there is a known family history and how severe the symptoms are, hemophilia may be diagnosed before birth, in early infancy, or later in life. Mild or moderate hemophilia might not be diagnosed until childhood or adulthood, because minor injuries can heal normally when there is enough clotting-factor activity. In these cases a bleeding problem may not be noticed until the person has surgery, a tooth removed, or a major injury.

Testing before birth#

If you or your partner are pregnant and there is a known genetic change in the family that you want to test for, there are two main options:

• Prenatal diagnostic testing — the change identified in the family can be tested for using chorionic villus sampling (CVS) or amniocentesis.
• Pre-implantation genetic diagnosis (PGD) — if you are undergoing IVF, embryos can be tested for the family’s gene change before implantation.

A genetic counselor can explore these options and their implications with you. There may be substantial costs involved, so it is worth clarifying these and any support available beforehand.

If you are pregnant and there is a family history but you do not know whether you carry the gene, tell the obstetrics team so they can plan a safe delivery with the hemophilia team.

Testing in babies#

If there is a known family history, a sample of your baby’s blood can be tested after birth to check clotting-factor levels. Testing is repeated at six months of age to confirm the results.

Where there is no known family history, children with severe hemophilia are usually diagnosed in their first year, when parents or health professionals notice unusual bruising or bleeding. Most babies with hemophilia do not have bleeding problems at birth, although some may. Hemophilia may be suspected if a baby:

• has internal bleeding, or unusual swelling or bruising after delivery
• continues to bleed after a heel prick (or after circumcision, if performed)
• has excessive bruising after immunization, or bruises easily
• is reluctant to use an arm or a leg, or has painful swelling

Growing up with hemophilia#

With treatment and support from a hemophilia treatment center, most people with hemophilia can live relatively normal, healthy lives. Unless there are complications, young people can expect to grow up with few or no joint problems, and with sensible precautions they can play most sports, exercise and look forward to a full and productive life.

As children grow, they learn to recognize when bleeding may be occurring. Even before pain or swelling is obvious, they may notice the “funny feeling” that is one of the earliest signs of a joint bleed. The specialist nurses and physiotherapists at your nearest hemophilia treatment center can advise parents and children at each stage of childhood.

Immunizations#

Children with hemophilia can have all the normal immunizations at the usual age. It is important to tell the nurse or doctor giving the immunization that the child has hemophilia. Injections can be given into the fatty tissue under the skin (subcutaneously) rather than into the muscle, with pressure applied afterwards, which reduces the risk of bruising and bleeding. This is not necessary for every child, so contact your treatment center for advice on how your child should be immunized.

Women who carry the gene#

Many women who carry the genetic change have no signs of a bleeding disorder, but some do — this is sometimes called having mild hemophilia. Symptoms of a bleeding tendency may include:

• excessive bleeding after dental extractions, other surgery or medical procedures
• bruising easily
• heavy menstrual bleeding, which may lead to low iron levels or anemia
• prolonged bleeding after childbirth

Factor levels can vary over a woman’s lifetime and between family members. A woman whose factor level is low will need a treatment plan to prevent bleeding problems and manage any that occur.

How is hemophilia treated?#

Specialist hemophilia treatment services bring together health professionals with expertise in bleeding disorders — including hematologists (doctors who specialize in blood disorders), hemophilia nurses, physiotherapists, and social workers or counselors. They can help you make a treatment plan and advise on living well with hemophilia. Treatment centers are usually located in major hospitals.

Your local team will help you learn to recognize a bleed, deal with it promptly, and prevent and rehabilitate injuries. Your hemophilia physiotherapist can develop an exercise program to help prevent bleeds, protect your joints and maintain a healthy body and mind.

Treatment products#

Treatments are broadly classified as preventative (where medicine is used to prevent bleeds — also known as prophylaxis) and on-demand (where medicine treats a bleed, or is given just before an event such as surgery, dental treatment or childbirth). Options include:

• Desmopressin — a synthetic hormone that releases the body’s stored factor VIII into the bloodstream to help blood clot. It can be given as a slow injection into a vein, an injection under the skin, or a nasal spray. It is not suitable for everyone, and is used for some people with mild hemophilia A and some women with bleeding-disorder symptoms.
• Clotting factor concentrates — concentrated clotting factor injected (“infused”) into a vein, at home or at a treatment center, on demand or as prophylaxis. Recombinant factor concentrate, the most widely used type, is made by genetic engineering and contains little or no material from human blood or animals. Plasma-derived factor concentrate is made from human blood plasma from blood donations, and is used when desmopressin is not suitable or treatment is likely to be needed for more than two to three days.
• Tranexamic acid — stops blood clots being dissolved once they form. It can help treat mouth or nosebleeds, gut bleeding or bleeding after dental work, and is usually taken as tablets, syrup or a mouthwash.
• Fibrin glue — a medical gel made from fibrinogen and thrombin (proteins that help blood clot), applied directly onto a wound to stop bleeding.
• Emicizumab — used only as a preventative treatment. People who have “breakthrough bleeds” while on emicizumab generally need to be treated with clotting factor concentrate; if they cannot give this at home, they will need to go to hospital.
• Hormone treatment, such as oral contraceptives, can help women with heavy menstrual bleeding and can increase factor VIII levels.

After treatment with a clotting-factor product, some people develop antibodies known as “inhibitors,” which make treatment less effective. There are several ways to treat inhibitors; many people overcome them, although others have ongoing problems.

How often is treatment needed?#

Treatment for moderate or severe hemophilia aims to prevent bleeding, pain and joint damage. In many countries, most children and young people with severe hemophilia are now treated with emicizumab. People with mild hemophilia usually do not need prophylaxis and only need treatment for a bleed when it occurs — typically after trauma or injury, or when preparing for surgery or dental work.

Planning a family#

For people with hemophilia, or women who carry the gene, planning a family can raise questions such as: What are my options? How can a mother who carries the gene plan for a safe pregnancy and delivery? Who will help? Your hemophilia treatment center can help with these questions, and it may also help to speak to a genetic counselor.

With good management, women who carry the altered gene have no more difficulty delivering a healthy baby than other mothers, but careful planning is important. This involves:

• ideally, talking to a hemophilia specialist before pregnancy, who may refer you to a genetic counselor
• once pregnancy is confirmed, contacting your treatment center for advice on local obstetric services experienced with hemophilia
• asking your hemophilia and obstetrics teams to consult with each other to plan a smooth, safe pregnancy and delivery and care for your newborn
• checking with your treatment center before any invasive procedure, such as chorionic villus sampling or amniocentesis
• discussing suitable choices for anesthesia, especially an epidural, with both teams

A normal vaginal delivery is usually recommended unless there are obstetric complications.

Identifying the sex of the baby#

If you are pregnant and know you carry the gene change, it is recommended that you find out the sex of the baby before birth, preferably with a test that has minimal risk to the fetus, such as an ultrasound or prenatal screening test. A male baby is more likely to be affected than a female. The couple can choose whether they want to be told the baby’s sex before delivery, even if the medical teams know it. If neither the couple nor the staff know the sex and no other testing has been done, the pregnancy and birth will be managed as though the baby is a male with hemophilia, to ensure a safe delivery.

Travel and hemophilia#

Everyone has individual needs when traveling. If you are planning a trip, contact your hemophilia treatment center a few months before departure. They can:

• advise on documentation, medication and travel insurance — for example, documentation to carry medication and equipment through security and customs may be required
• provide contact details for hemophilia treatment services along your route or at your destination in case of an emergency
• advise you on what to do if you need treatment while traveling

Be sure to get travel insurance for overseas travel, and consider telling your traveling companions what to do in an emergency.

Physical activity#

Physical activity is good for everyone. For people with hemophilia it can strengthen joints and muscles and help prevent bleeds. Speak to your doctor about what kinds of activity may best suit you. Everyone has a different “bleed history,” so advice needs to be tailored to the individual.

Choose something that appeals to you and is unlikely to aggravate any injuries or problem joints. Rough, high-contact sports such as football and boxing are not usually recommended, as they may cause bleeds. Low-impact or non-contact activities are generally best, for example:

• swimming or hydrotherapy, cycling, hiking, rowing, paddle boarding
• gym-based programs, dance, pilates or yoga
• rock climbing (with a safety rope), surfing, dancing

Medical identification#

People with hemophilia are advised to wear a medical ID tag — a small tag worn on a bracelet, neck chain or clothing. The aim is to alert people in an emergency that you have hemophilia and may need urgent medical attention.

Support#

Hemophilia treatment centers provide treatment and support for people living with hemophilia and their families. Support organizations and groups can connect you with other individuals and families affected by hemophilia.

Key points#

• Hemophilia is caused when the blood does not have enough clotting factor.
• It cannot be cured, but with current clotting-factor treatments it can be managed effectively.
• Internal bleeding episodes, or “bleeds,” are the main problem for most people with hemophilia.
• Bleeds are most commonly into joints or muscles.
• Bleeds can happen without an obvious cause, or as a result of injury.

Where to get help#