Hemophilia in Children

Hemophilia is a rare genetic condition that prevents blood from clotting properly, leading to excessive bleeding. If the symptoms are left untreated, prolonged bleeding can lead to serious complications, including death.

Normal blood contains clotting factors (proteins) and platelets (small cells that assist in the formation of clots) that help stop bleeding. In children with hemophilia, there’s a lack of one of these essential clotting factors, making it harder for bleeding to stop, even with minor injuries.

Bleeding may happen inside the body, such as in joints or muscles, after an injury. In some cases, it can also occur without any clear cause.

While hemophilia has no cure, treatment can prevent bleeding and complications by regularly replacing the low or missing clotting factor or with other medications that improve the function of the clotting system.

Types of Hemophilia

The type and severity of hemophilia depends on the levels of blood clotting factor in the blood. Lower factor levels in the blood result in more severe symptoms and higher health risks.

The primary types of hemophilia are:

Hemophilia A: The most common type, caused by low or missing factor VIII. It is four times more common than hemophilia B, and half of those with hemophilia A experience severe symptoms.
Hemophilia B: This type is due to a low or missing factor IX. A rare form of this type, called hemophilia B Leyden, may cause excessive bleeding in childhood, which usually improves after puberty.

Von Willebrand Disease

Von Willebrand disease (VWD) is another type of bleeding disorder that affects blood clotting. VWD is more common than hemophilia, impacting about 1 in every 100 people, although many cases are mild and go undiagnosed. Unlike hemophilia, which primarily affects males, VWD affects both males and females equally.

While both VWD and hemophilia impair the blood’s ability to form clots, their causes differ. VWD is caused by a deficiency or dysfunction of von Willebrand factor (VWF), a protein that helps blood platelets stick together and stabilize factor VIII, another essential clotting protein. Because of this, people with VWD may also have low levels of factor VIII, like hemophilia A. However, VWD symptoms are typically milder and involve nosebleeds, heavy menstrual bleeding, and prolonged bleeding from minor cuts.

Causes and Risk Factors of Hemophilia

Hemophilia is caused by mutations in the genes responsible for making clotting factor proteins primarily factor VIII and factor IX. There is a family history in most cases, but 30% of cases have no family history. Hemophilia A and B occur more often in males due to the way the mutations are inherited.

Acquired hemophilia develops later in life when the immune system attacks clotting factors. It’s often linked to autoimmune diseases, pregnancy, and cancer.

Signs and Symptoms of Hemophilia

Hemophilia is most often detected during infancy or early childhood. Symptoms in babies and young children with the condition include prolonged bleeding after:

Blood draws for newborn screening tests
Circumcision
Complications during difficult deliveries, particularly bleeding in the scalp or brain
Routine vitamin K shots

In older children and adults, common symptoms include:

Bleeding after dental work or loss of teeth
Bleeding into a muscle or joint, which causes pain, swelling, warmth or decreased motion
Unexpected bleeding after injuries, surgery, or vaccinations
Blood in the urine or stool
Easy bruising or blood buildup under the skin (hematoma)
Frequent nosebleeds

Head injuries, even minor ones, can be serious for children with hemophilia, especially if they cause bleeding in the brain. Symptoms of brain bleeds include:

Convulsions or seizures
Double vision
Headache that is painful and prolonged
Loss of consciousness
Nausea and vomiting
Repeated vomiting
Sensitivity to light
Sleepiness or lethargy
Sudden weakness or clumsiness

Call 911 if your child has these symptoms, bleeding that won’t stop, or hot, swollen joints that are painful to bend.

Diagnoses and Tests for Hemophilia

Children with severe hemophilia are usually diagnosed in infancy. To diagnose hemophilia, the doctor considers your child’s medical history and symptoms and conducts a physical exam.

Diagnosis may also include:

Coagulation tests to check the body’s ability to form a blood clot and measure how long it takes.
Complete blood count (CBC) to determine the number platelets, which help form clots.
Clotting factor tests (factor assays) to diagnose the specific cause of the disorder.
Genetic tests to provide more information, establish a prognosis, and treatment options.

Treatment for Hemophilia

Children with hemophilia can lead active lives with regular treatment. Treatment options depend on your child’s age, type, and severity of hemophilia.

The primary treatment for hemophilia is replacement therapy, where the missing clotting factors are infused through a vein (regular intravenous infusion). Clotting factors used during this therapy may be made from purified human plasma but currently, it is often made synthetically, meaning without the use of human plasma, often called recombinant clotting factors.

Children with severe hemophilia may receive continuous replacement (prophylactic) therapy, which can be done at home.

Replacement therapy can increase clotting levels to prevent or treat a bleeding episode. Children with mild or moderate hemophilia may only require therapy before surgery or other procedures that put them at risk.

Newer treatments include medications that are easier to give (subcutaneously or under the skin rather than into the vein) and these work by enhancing the clotting process without replacing the missing factor.

Other preventative treatment options include:

Blood transfusions in case of significant blood loss.
Dental hygiene practices to prevent bleeding, such as gently brushing twice a day and flossing daily.
First aid, such as applying pressure and bandages, for minor injuries.
Medications to help form blood clots, prevent bleeding, and promote healing.
Gene therapy corrects the faulty pieces of genetic code by adding a functional copy of the gene to treat the disease. Treatments directly target the root cause of hemophilia A and B, adding specific and functional genes which results in the patient being able to make their own factor like people without hemophilia. Children’s Hospital Los Angeles is a national leader in gene therapy, offering cutting-edge treatments and standing among the few centers in the country to provide gene therapy for both hemophilia A and B. Eligible patients also have access to clinical trials for advanced treatments, providing them with the most innovative care before widely accessible.

Gene Therapy Treatments for Hemophilia

Gene therapy is a newer, cutting-edge treatment that corrects the genetic defect by providing a functional (healthy) copy of the genes causing hemophilia A and B. Treatment helps the body produce the necessary proteins to reduce or stop the need for regular transfusions. Roctavian™ (treats hemophilia A) and Hemgenix® (treats hemophilia B) are both FDA-approved single-dose treatment options offered at CHLA for males 18 and older. CHLA is one of the few pediatric centers in the nation offering Roctavian and Hemgenix therapies and is a leading authority in gene therapy. Learn more about cell and gene therapy at CHLA.

Hemophilia Care at Children’s Hospital Los Angeles

Our Hemostasis and Thrombosis Center is one of the world’s largest centers for pediatric bleeding and clotting disorders, providing specialized care and the best available treatment options for children with hemophilia. As a leader in gene therapy, we offer cutting-edge treatments to support patients and their families through expert, compassionate care. Learn more about our commitment to advancing care at our Hemostasis and Thrombosis Center.