What is hemophilia?
Hemophilia is a rare inherited
condition that affects the blood’s ability to clot effectively. The process of
blood clotting helps the body with wound healing and repair. When a healthy person
gets a cut, a type of cell in the blood called platelets stick to the wound to
try to plug the cut. The platelets release chemical signals calling for help
from other platelets and special proteins in the blood called clotting
factors. These clotting factors bind
together to form chains, called “fibrin”. The fibrin forms a net around the
platelets preventing them from going back into the bloodstream and holds the
clot together to help seal the wound.
There are many different
clotting factors, and each one is needed for the fibrin net to form properly. They
work together. In most people with
hemophilia, levels of either clotting factor VIII (8) or IX (9) are too low so
the clotting process slows.
This does not mean
that when injured a person with hemophilia will bleed more quickly than a
person without hemophilia; they will,
however, bleed for a longer period of time.
Different types of hemophilia
Hemophilia A – there
is a low level or absent level of clotting factor VIII. This is the most common
type of hemophilia, affecting about 80% of people with hemophilia.
Hemophilia B – there
is a low level or absent level of clotting factor IX. Only about 20% of people
with hemophilia have this type.
||Greater than 5% up to 40%|
||Between 1% to 5%|
||Less than 1%|
How is hemophilia inherited?
hemophilia is an inherited condition. This means that it is passed from parents
to their children. Hemophilia is caused when there is a mutation, “a mix-up”,
in one of the genes on the X chromosome. Females have two X chromosomes, while males
have one X chromosome and one Y chromosome. For this reason, males and females are affected differently. If a person has at least one normal gene, they will not have hemophilia.
Mothers with the
hemophilia gene can pass it on to either their sons or daughters. Their sons
may have hemophilia, and their daughters may be carriers, but their children
could also be unaffected. There is 50% chance of having a boy with hemophilia
if the mother is a carrier, and 50% chance of having a girl who is a carrier.
hemophilia will not have sons with hemophilia. However, their daughters will
always be carriers.
How does the hemophilia gene affect males and females differently?
Hemophilia most often affects males; females may be carriers of the condition.
If a female has the
hemophilia gene on one of her X chromosomes, she will either not be affected or
will experience only very mild bleeding symptoms, such as heavier
periods. She would be a “carrier”,
meaning that while she is not affected, but she could pass hemophilia to her
son. For a female to have hemophilia,
she must receive the hemophilia gene from both parents.
Males have only one X
chromosome, and therefore only require one X chromosome with the hemophilia
gene to have the condition. Males can only get the X chromosome from their
mother. Their father always passes on the Y chromosome.
Symptoms of hemophilia
If your child is experiencing any of the following symptoms, you should talk to your doctor about the possibility that your child might have hemophilia:
- prolonged bleeding after circumcision
- easy bruising
- joint and muscle swelling
- prolonged bleeding after cuts, surgery, bloodwork or dental procedures
- mouth bleeds
Symptoms depend on the severity of hemophilia. The severity of hemophilia depends on the levels of clotting factors in the blood.
For mild hemophilia,
children typically do not have symptoms for many years. They may have prolonged bleeding after
surgery, trauma or dental procedures, such as pulling a tooth.
hemophilia, children may bruise easily or may have internal bleeding in their
joints especially after a fall/trauma.
For severe hemophilia, the symptoms are similar
to children with moderate hemophilia except that bleeding is more frequent and
more severe. They may have bleeding for no apparent reason in the joints, muscles or internally. Without treatment, people with severe hemophilia can develop serious internal bleeding and long term joint damage from bleeds.
Diagnosis of hemophilia
you know that hemophilia runs in your family, you might choose to have your
baby tested while it is still in the womb (prenatal testing). If prenatal testing is not completed but the
woman is carrying a male fetus it is best to assume that the child has
hemophilia and to take appropriate steps during the birthing.
In cases where there
is no known family history of hemophilia, it may not be diagnosed until parents
begin to notice bleeding symptoms. A blood test can confirm the diagnosis of hemophilia
as well as how severe it is and whether it is hemophilia A or B.
Treatment of hemophilia
Hemophilia is a lifelong condition that will require regular care. There are several treatment methods for hemophilia. The method and timing of treatment chosen will depend on the type and severity of your child’s hemophilia, and will be discussed with their health care team.
On demand treatment
If your child has
mild hemophilia, or bleeds infrequently, their health care team may choose to give
them a dose of clotting factor only when an injury occurs.
Prophylaxis (or preventative treatment)
If your child has
severe hemophilia, or has severe bleeds often, they may need
clotting factor on a regular basis to prevent bleeds from happening. Regularity
of dose may be anywhere from once a day to weekly.
Treatments by type
- Factor VIII (FVIII) concentrate injected directly into a vein through an intravenous infusion.
- People with milder forms of hemophilia can take a synthetic (man-made) hormone, DDAVP, which triggers the body to release factor VIII.
- Factor IX (FIX) concentrate injected directly into a vein through an intravenous infusion.
People with mild or moderate hemophilia A might be treated with a medication called Desmopressin (DDAVP) for mild to moderate bleeds. DDAVP is a chemical that helps to release factor VIII that is already stored in the body. Before using this method, your child’s health care team will perform a “DDAVP Challenge”. This is a test that will allow them to see if the use of DDAVP releases enough factor VIII in your child’s body to prevent and treat bleeds. Treatment of hemophilia with DDAVP is not recommended until your child is at least three years of age.
Hemophilia comprehensive health care team
There is excellent medical treatment for people with hemophilia. You and your child can look forward to living complete, happy and normal lives with the support of a comprehensive team of health care specialists. This team will include a nurse coordinator, hematologist (blood doctor), physiotherapist, and social worker.
- People with hemophilia can live happy and normal lives with the support of a comprehensive health care team.
- Hemophilia is a lifelong condition that is passed down from parents to children.
- Hemophilia affects mostly boys. Girls are usually carriers.
- Severity of hemophilia can vary, and thus treatments do as well. Options will be discussed between you and your child’s comprehensive care team.