What is thrombosis?

Thrombosis is a blood clot that develops within veins or sometimes arteries in the body. Thrombosis may be serious or inconvenient but often occurs as a complication of a procedure, medication, or other disease. If left untreated a thrombosis can cause long-term problems; such as chronic swelling, pain, or even permanent damage to internal organs.

Thrombophilia refers to anything that increases one’s tendency to develop blood clots. Thrombosis in children is uncommon and is most often seen in children with complex medical problems or procedures. Thrombophilia can be considered the opposite of hemophilia, a disorder that prevents blood from clotting.

How is thrombophilia classified?

Thrombophilia refers to a group of disorders that increases a child’s tendency to develop dangerous blood clots. There are two main types of thrombophilia:

  • Inherited thrombophilia is caused by certain genetic conditions.
  • Acquired thrombophilia is caused by lifestyle factors or medical conditions, including immobility, obesity, sedentary lifestyle, trauma, smoking, or oral contraceptive use.

How we care for thrombosis

Children and young adults with blood clots are treated through the Dana-Farber/Boston Children’s Thrombosis and Anticoagulation Program. Through our unique program, we can quickly identify children who need anticoagulation medications (or “blood-thinners”) using established monitoring and risk identification guidelines. Children outside of the hospital visit our outpatient center staffed by pediatric hematologists and pediatric hematology nurse practitioners with specialized expertise in the diagnosis and treatment of thrombosis.

Our areas of research for thrombosis

For many children with rare or hard-to-treat conditions, clinical trials provide new options. Participation in any clinical trial is completely voluntary. We will take care to fully explain all elements of the treatment plan prior to the start of the trial, and you may remove your child from the medical study at any time. Currently, our hematology team is studying several new oral blood thinners in children for treatment and prevention of blood clots. We are also involved in an international study of the length of anticoagulation needed to treat thrombosis. Your hematologist may mention opportunities to participate in these studies, but you should feel free to ask about current research studies relevant to your child.

Researchers at Dana-Farber/Boston Children’s perform scientific and clinical research on platelets and related aspects of hemostasis and thrombosis. A particular focus is antiplatelet therapy, including the characterization of:

  • how newly discovered molecules and mechanisms could help control platelets and clotting
  • how antiplatelet drugs affect normal blood clotting (coagulation) and aspects of the immune system (e.g., inflammation)
  • the relationship between the strength of antiplatelet treatments and the balance between thrombosis (uncontrolled clotting) and hemorrhage (uncontrolled bleeding)
  • how tests of platelet function could help guide antiplatelet therapy in the clinic