Hemophilia is an
inherited bleeding disorder in which the blood does not clot normally because of
a missing or dysfunctional clotting protein. Clotting proteins, also called
clotting factors, work with other blood components – such as platelets, von Willebrand factor, and other proteins – to form a blood clot. When any of these
components is absent or low, increased bleeding can result. If clotting factor VIII
(8) or factor IX (9) are affected, this bleeding disorder is called hemophilia.
Hemophilia has two main types based on which blood clotting
factor is abnormally low.
- Hemophilia
A is caused by absent or low level of factor VIII (8).
- Hemophilia B is caused by absent
or low level of factor IX (9).
Normal plasma levels of
factor VIII and IX range from 50% to 150%. Individuals with severe hemophilia
have <1% of factor in their blood, moderate hemophilia 1-<5%, and mild 5-<50%.
Hemophilia symptoms
The
most common hemophilia symptoms are excessive bleeding, typically into the
muscles and the joints. Children with mild hemophilia may have no bleeding
episodes until they have surgery, a dental procedure, or experience a trauma.
Children with severe hemophilia can bleed spontaneously (no injury) into
joints, muscles, or other organs.
Other hemophilia symptoms may include:
- Bruises from
small accidents, which may result in large hematomas (collections of blood
under the skin that cause swelling)
- Nosebleeds
that are difficult to control
- Blood in the
urine or stool
- Muscle bleeds
that cause swelling and pain
- Joint bleeds,
which cause pain, swelling and immobility
- Internal
bleeding such as head bleeds (potentially life-threatening)
It is important to understand
that some symptoms of hemophilia may resemble those of other more common medical
problems. Because some of these symptoms can also point to other conditions,
it’s important to have your child evaluated by a qualified medical professional
for an accurate diagnosis and prompt treatment.
Hemophilia causes
Hemophilia A and B are
inherited disorders. The abnormal factor VIII or IX gene is passed from parent
to child on the X-chromosome. About one-third of cases develop from new gene
variants in an individual, and there is no family history. Males have one X and
one Y chromosome (XY), while females have two X chromosomes (XX). A male who has
a hemophilia gene on his X chromosome will have hemophilia of some severity. If
a female inherits a hemophilia gene, she will typically have one normal factor
gene and one abnormal factor gene. This is referred to as a “carrier.” Usually,
the one normal factor gene is enough to produce normal levels of factor;
however, in some cases females may have mild deficiency of factor VIII or IX
levels and have bleeding symptoms. In rare cases, females can have severe
factor deficiency.
If your child is suspected of
having hemophilia, he or she will be referred to a hematologist, a doctor with
specialized training in treating blood disorders. Blood tests often include:
- Prothrombin time (PT) and an activated
partial thromboplastin time (PTT) – these tests look at general blood
clotting and screen for possible deficiency of different blood clotting
proteins including factor XIII and factor IX.
- Levels of specific clotting factors, if
there is a concern for a deficiency of factor VIII or IX
- Genetic testing to identify the specific
mutation (pathogenic variant) responsible for the “hemophilia gene.” This
may be particularly important for possible female carriers whose factor
level is in the normal range.
Other diagnostic tests may be necessary depending on your child's
individual situation. Once all necessary tests are completed, our experts meet with
you to review what they have learned about your child's results and to outline
the best possible treatment options.
The approach to treatment
depends on the hemophilia type and severity and the individual’s bleeding
symptoms. Our goal is to prevent spontaneous bleeding in severe hemophilia
patients and to quickly treat and control bleeding symptoms due to injury that
occur in patients with all types and severities of hemophilia.
Your child's hemophilia treatment may include:
- Factor
replacement therapy. Special concentrates of factor VIII (8) and factor IX
(9) protein are available for Hemophilia A or Hemophilia B, respectively.
The factor concentrates are administered by infusion (injections into a
vein) and allow us to replace the missing or low clotting factor. We use
these infusions of factor concentrate to both prevent and treat bleeding and
promote healing. Patients will often receive Factor replacement therapy
prior to (and sometimes after) surgery
or procedures such as dental work. Individuals with severe hemophilia A or
B receive regularly scheduled home infusions of factor concentrates,
called prophylaxis, to help prevent frequent bleeding symptoms.
- Desmopressin, a synthetic hormone known as DDAVP that your child
may receive if he has mild hemophilia A. This can be administered as a
nasal spray, Stimate®, or by infusion into the vein like
factor concentrate.
- Antifibrinolytic agents. Oral medicines such as aminocaproic acid
and tranexamic acid can be used to help make clots more stable. These
medications may be particularly helpful for managing bloody noses
(epistaxis), heavy menstrual bleeding, and after dental procedures for
patients with bleeding disorders.They may be used alone or together with DDAVP or factor
replacement therapy.
During the course of treating your child's
hemophilia, your child’s doctor will likely recommend several preventative
measures including:
- Giving routine immunizations
subcutaneously (under the skin) rather than in the muscle to prevent deep
muscle bleeds. This is important for your pediatrician to know.
- Avoiding
aspirin and ibuprofen (NSAIDs), as well as products containing them. These
medications can affect platelet function and may increase bleeding
symptoms in persons with hemophilia.
- Routine (yearly) evaluations at a Comprehensive
Hemophilia Treatment Center to ensure screenings, such as assessment of joint
and muscle health by a physical therapist, and up-to-date bleeding
management plans are in place.
Your child is
an individual, and your hemophilia team will take many factors into account to
ensure the best treatment and follow-up plan for your child including:
- Your
child's age, overall health, and medical history
- The severity
of the disease
- Your
child's tolerance for certain medications, procedures, or therapies
- How your
child's doctors expect the disease to progress
- Your opinion and preferences
Clinical Trials
For many children with rare or hard-to-treat conditions, clinical trials
provide new treatment options. Participation in clinical trials has risks and
benefits, but it is through clinical trials and clinical research studies that
we are able to forward the field of hemophilia and other bleeding disorders.
Participation in a clinical trial is
always completely voluntary. The doctor leading the clinical trial (study) at
the site will review with you in detail the purpose of the study and what is
required of you/your child during the course of the study before you agree to participate.
Hemophilia is a lifelong
condition, but the quality of life for patients with hemophilia is better now
than ever before due to access to factor replacement therapy and comprehensive
specialized hemophilia care. Today, children with hemophilia of all severity
levels have regular attendance at school, and participate in school and
community activities and many types of sports. Children with hemophilia need regular medical follow-up and
preventative health screenings. Your child's pediatrician should give routine immunizations subcutaneously (under the skin) to prevent deep
muscle bleeds. Your child should
avoid aspirin and ibuprofen
(NSAIDS), as well as products containing them, since they have been linked to
bleeding problems.