By: Jayson Stoffman, MD, FRCPC, FAAP
Our body has a variety of important ways to protect us from too much bleeding after we get injured. Unfortunately, sometimes children are born with (inherit) a blood condition that causes mild or even severe bleeding after injuries or surgery. This is because their blood does not clot normally to control the bleeding.
Fortunately, there are treatments for these pediatric bleeding disorders. Learn more here.
What are the symptoms of bleeding disorders in children?
Children with bleeding disorders can have mild or severe bleeding symptoms.
Mild bleeding disorders
Common symptoms in children born with mild bleeding disorders include easy skin bruising or bleeding from the gums or nose. Adolescents may have heavy menstrual periods. Some children born with mild bleeding disorders only have heavy bleeding after injuries or surgeries.
Severe bleeding disorders
Children with severe bleeding disorders often have bruising or too much bleeding noticed at or soon after birth. In these children, heavy bleeding can happen in the skin, gums, and nose. in addition to the brain, intestines, joints, or muscles after major, minor, or no known injuries.
How does the blood normally clot after injury?
Some injuries to the body cause breaks in blood vessels, the tubes that carry blood. The broken blood vessels contract or narrow to decrease the blood flow out of the body. Then, cells in the blood called platelets plug the holes by sticking to the blood vessel and to other platelets with the help of a protein called von Willebrand factor (vWF). To make the plug more stable, a cascade of blood proteins called coagulation or clotting factors (including Factor VIII and Factor IX, discussed below) are released to build a solid clot.
What are the most common types of bleeding disorders in children?
Two of the most common types of bleeding disorders are von Willebrand disease and hemophilia.
What is von Willebrand disease?
Von Willebrand disease (vWD) is a group of bleeding disorders caused by problems with a blood clotting protein called von Willebrand factor (vWF). vWD can be inherited in an "autosomal dominant" way. This means that if one parent has vWD, then there is a 50% chance of passing it on to each child.
The most common inherited type of vWD is type 1 vWD. About 1 in 20 people are born with this bleeding disorder. In the blood of a child born with type 1 vWD, the amount of vWF is less than normal.
Other types of vWD are more rare. In the blood of a child with type 2 vWD, the amount of vWF might be normal but it doesn't work properly. In the blood of a child with type 3 vWD , vWF is missing. Although type 3 vWD causes the most severe bleeding issues, it is also the most rare type.
How is von Willebrand disease treated?
Fortunately, most children born with vWD will have mild bleeding problems, which occur rarely. So, often there is no need for regular medications. However, some adolescents and adults who menstruate can have heavy periods that need control with hormones.
The medications to prevent or treat excess bleeding from surgeries, dental extractions or injuries in children with vWD depend on the type of vWD and the actual symptoms.
Most children with Type 1 vWD who have bleeding problems can use a medication called desmopressin, which can be given as a shot under the skin, into a vein or as a spray into the nose. Desmopression helps the body release vWF stored in the lining of blood vessels to create a blood clot. Desmopressin also helps some children with Type 2 vWD.
Another treatment is to replace the missing or abnormal vWF with an intravenous (into the vein) vWF collected from donated blood plasma. vWF concentrate is helpful to treat bleeding for all people with Type 3 vWD and some with type 1 and 2 vWD. A new, recombinant (genetically created) vWF concentrate is being developed to replace the blood-donated versions.
What is hemophilia?
The hemophilias are a group of inherited bleeding disorders caused by deficient or missing clotting factors called Factor VIII deficiency (or Hemophilia A) or Factor IX deficiency (or Hemophilia B). Without these clotting factors, a stable blood clot cannot form and a child with hemophilia can have severe bleeding symptoms at birth.
Hemophilia A and Hemophilia B result from inheriting a mutation on the X chromosome from a parent. While hemophilia and severe bleeding most often occur in males who have one X and one Y chromosome, females who have two X chromosome (with one copy of the normal factor gene) can be carriers for hemophilia with no symptoms or mild bleeding symptoms. One third of people with hemophilia have a new mutation, while the other two-thirds usually have a family history in uncles or grandfathers.
How is hemophilia treated?
Treatment of Hemophilia A and B has traditionally focused on replacing the missing clotting factor.
Most boys with Hemophilia A and many with Hemophilia B are treated prophylactically (preventatively) with intravenous clotting factor replacement on a regular basis. Preventative doses minimize the risk of bleeding, including minor bleeds which still cause long-term joint damage. Boys will also be treated "on demand" when they have an injury or bleeding symptoms.
Since clotting factor replacement must be given intravenously, parents and eventually the children are taught to infuse at a very young age. Unfortunately, this hemophilia treatment can result in unwanted development of inhibitors or antibodies (immune proteins) that make the replacement clotting factor not work anymore, causing bleeding to continue.
More promising hemophilia treatments on the horizon
Better therapies for hemophilia are becoming more widely available. Longer-acting intravenous factor replacements have been developed, which provide protection from bleeding with fewer doses. Emicizumab is an antibody given subcutaneously (under the skin) which performs the role of Factor VIII without actually replacing Factor VIII. As a result, it does not cause and is not affected by inhibitors.
Other non-replacement therapies are also in development for hemophilia. Gene therapies trials are underway in both Hemophilia A and B, and the U.S. Food & Drug Administration (FDA
) recently approved the first gene therapy to treat adults with hemophilia B. The introduction of a functional gene that makes the body produce its own Factor VIII or Factor IX holds great promise of an eventual cure for the hemophilias.
What if my child has symptoms or episodes of abnormal bleeding?
If your child at any age has mild bleeding symptoms, contact your pediatrician for a complete and thorough evaluation. If your child experiences severe bleeding symptoms, try to control the bleeding by applying pressure, and immediately contact your pediatrician or seek medical attention at your nearest emergency department.
Most children with bleeding symptoms will require additional consultation with a pediatric hematologist. An evaluation for the causes of bleeding include a complete personal and family history, physical examination, and special blood testing.
Hemophilia Treatment Centers are special federally funded clinics that provide current medications and supportive care to children and adults.
About Dr. Stoffman
Jayson Stoffman, MD, FRCPC, FAAP, is a pediatric hematologist/oncologist in Winnipeg, Manitoba, Canada. His main interests are treatment of children with bleeding and clotting disorders, and abnormalities of the red blood cell such as sickle cell and thalassemia. He is also very involved in education and advocacy for patients, families and healthcare providers.