HemophiliaWhat is hemophilia?Hemophilia is an inherited bleeding, or coagulation, disorder.
Children with hemophilia lack the ability to stop bleeding because of the
low levels, or complete absence, of specific proteins, called "factors,"
in their blood that are necessary for clotting. Proper clotting of blood
helps prevent excessive bleeding.
In the US, there are about 20,000 people with hemophilia. Each year,
approximately 400 babies are born with the disorder.
What are the different types of hemophilia?There are many factors in the blood that are involved in the
function of forming clots to stop bleeding. A child with hemophilia is
missing, or has a low supply of, one of the factors needed in order for
the blood to clot. Two factors that affect blood clotting are factor VIII
and factor IX. Hemophilia is classified by its level of severity.
Hemophilia may be mild, moderate, or severe, depending upon the level of
the blood clotting factors in the blood.
The three main forms of hemophilia include the following:
- hemophilia A - caused by a lack of the blood clotting factor
VIII; approximately 85 percent of hemophiliacs have type A disease.
- hemophilia B - caused by a deficiency of factor IX.
- von Willebrand disease - a part of the factor VIII molecule
known as von Willebrand factor or ristocetin cofactor is reduced. The
von Willebrand factor involves helping the platelets (blood cells that
control bleeding) attach to the lining of a vein or artery. This missing
factor results in prolonged bleeding time because the platelets are
unable to attach to the wall of the vessel and form a plug to stop the
bleeding.
What causes hemophilia?Hemophilia types A and B are inherited diseases passed on to children
from a gene located on the X chromosome. Females have two X chromosomes,
while males have one X and one Y chromosome. A female carrier of
hemophilia has the hemophilia gene on one of her X chromosomes. When a
hemophilia carrier female is pregnant, there is a 50/50 chance that the
hemophilia gene will be passed on. If the gene is passed on to a son, he
will have the disease. If the gene is passed on to a daughter, she will be
a carrier. If the father has hemophilia but the mother does not carry the
hemophilia gene, then none of the sons will have hemophilia disease, but
all of the daughters will be carriers.
In about one-third of the children with hemophilia, there is no family
history of the disorder. It is believed that, in these cases, the disorder
could be related to a new gene mutation. Tests are available to possible
carriers to help determine whether or not they, in fact, carry the
abnormal gene.
Carriers of the hemophilia gene usually have normal levels of clotting
factors but may bruise easily, may bleed more with surgeries and dental
work, and/or have frequent nosebleeds or excessive menstrual bleeding.
With von Willebrand disease, the missing protein, von Willebrand factor
(vWF), is not on the X chromosome, but on a chromosome that is not gender
determined; so, the disease can affect both males and females equally. Its
inheritance is autosomal dominant, which means that a parent with the gene
has a 50/50 chance to pass it on. It is believed that approximately 2
percent of the US population suffers from this type of bleeding disorder.
Children with von Willebrand disease may have inherited the disorder or
it is possible to have had the disease caused by certain medications,
autoimmune disorders, kidney problems, and certain forms of cancer.
What are the symptoms of hemophilia?Because hemophilia is a bleeding disorder, the most common symptom of
the disorder is excessive, uncontrollable bleeding. Hemophiliacs do not
bleed faster than normal children; they bleed for a longer time.
The severity of hemophilia is determined by the amount of clotting
factors in the blood. Those affected with hemophilia that have levels in
the 10 percent range (100 percent being average for unaffected children)
usually experience bleeding only with major surgeries or tooth
extractions. These children may not even be diagnosed until bleeding
complications from a surgery occur.
Severe hemophilia is when the factor VIII or IX is less than 1 percent.
Bleeding can occur with these children with the minimal activity of daily
life, and bleeding may also occur from no known injury. Bleeding most
often occurs in the joints and in the head.
Other symptoms of hemophilia include:
- bruising
Bruises can occur from small accidents, which can result in a large
hematoma (a collection of blood under the skin causing swelling). For
this reason, most diagnoses occur around 12 to 18 months of age, when
the child is becoming more active.
- bleeds easily
A tendency to bleed from the nose, mouth, and gums with minor
trauma, teeth brushing, and/or dental work is often an indication of
hemophilia.
- bleeding into a joint
Hemarthrosis (bleeding into a joint) can cause pain, immobility, and
eventually deformity if not medically managed properly. This is the most
common site of complications due to hemophilia bleeding. These joint
bleeds can lead to chronic, painful, arthritis, deformity, and crippling
with repeated occurrences.
- bleeding into the muscles
Bleeding into the muscles can cause swelling, pain, and redness.
Swelling from excessive blood in these areas can cause increased
pressure on tissues and nerves in the area, resulting in permanent
damage and/or deformity.
- bleeding from injury or bleeding in the brain
Bleeding from injury, or spontaneously in the brain, is the most common
cause of death in children with hemophilia and the most serious bleeding
complication. A brain hemorrhage can occur from even a small bump on the
head or a fall. Small bleeds in the brain can result in blindness,
retardation, a variety of neurological deficits, and can lead to death
if not recognized and treated immediately.
- other sources of bleeding
Blood found in the urine or stool may also be a symptom of hemophilia.
The symptoms of hemophilia may resemble other blood disorders or
medical problems. Always consult your child's physician for a diagnosis.
How is hemophilia diagnosed?In addition to a complete medical history and physical
examination, your child's physician may perform numerous blood tests
including clotting factor levels, a complete blood count (CBC), assessment
of bleeding times, and/or DNA testing. Your child's physician may also
request details about your child's family history.
Treatments for hemophilia:Specific treatment for hemophilia will be determined by your
child's physician based on:
- your child's age, overall health, and medical history
- extent of the disease
- your child's tolerance for specific medications, procedures, or
therapies
- expectations for the course of the disease
- your opinion or preference
Treatment depends on the type and severity of the hemophilia. Treatment
for hemophilia is aimed at prevention of bleeding complications (primarily
head and joint bleeds). Treatment may include:
- Parents may want to purchase soft toys with rounded corners for
young children. Padded clothing and helmets may be necessary for the
child that is learning to walk or becoming more active. Contact sports
in school should be evaluated for risks of injury to the child.
- Immunizations may need to be given under the skin (subcutaneous)
instead of in the muscle (intra muscular) to prevent deep muscle bleeds.
- Joint hemorrhages may require surgery and/or immobilization.
Rehabilitation of the affected joint may include physical therapy and
exercise to strengthen the muscles around the area.
- Before surgery, including dental work, your child's physician may
recommend factor replacement infusions to increase the child's clotting
levels prior to the procedures. Your child may also receive the specific
factor replacement infusions during and after the procedure to maintain
the clotting factor levels and to improve healing and prevention of
bleeding after the procedure.
- Your child's physician may also recommend the discontinuation of
aspirin, and aspirin-containing products, since these products have been
linked to bleeding problems.
- Blood transfusions may be necessary if significant blood loss has
occurred.
- Proper dental hygiene is a preventive measure.
Long-term outlook for children
with hemophilia:Hemophilia is a lifelong disease. With the advances of specific
clotting factors in laboratories, prevention and treatment of bleeds is
improving.
With careful management, informed decisions, and recognition of complications,
many children with hemophilia can live relatively healthy lives
with a normal lifespan.
More Information
Schneider Children's
Hospital Division of Hematology/Oncology
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