For many people with non-cancerous, or benign, bleeding disorders like hemophilia, finding expert treatment is critical. Robert Bona, MD, director of the Classical Hematology Program, notes the strong partnerships across Yale School of Medicine in support of patients with these disorders.
“In hematology, we have strong partners in laboratory medicine around coagulation and hemostasis, and transfusion medicine. Both programs are superb. It is difficult to run a first-rate hemophilia clinic or a hematology program without that really excellent support,” explained Bona. “We also have a great genetics program at Yale. We are getting more molecular-based in the diagnosis and the treatment of these so called benign disorders.”
The most common benign conditions cared for by Yale’s hematologists are:
- Hemophilia: Hemophilia is an inherited disorder in which the affected person’s blood has difficulty clotting. The disease is caused by deficiencies in coagulation protein factor VIII (hemophilia A) and coagulation protein factor IX (hemophilia B). Severity can vary from patient to patient. Treatment has changed dramatically over the years, but currently, the options include a variety of recombinant factor replacement products or a drug called emicizumab, an antibody that simulates factor VIII function. Clinical trials are underway using gene therapy for both hemophilia A and B. Per the Centers for Disease Control and Prevention (CDC), hemophilia affects 33,000 males in the United States. While less common, hemophilia may occur in women. In addition, women who are carriers of the abnormal gene may also have bleeding symptoms.
- Von Willebrand Disease: Though not as well-known as hemophilia, the most common inherited bleeding disorder is von Willebrand disease (VWD), which is caused by defects in a blood substance, von Willebrand factor, that helps clots form. Von Willebrand factor helps the blood platelets adhere to an injured area. According to the CDC, more than 15,000 people in the U.S. are undergoing treatment for VWD at hemophilia treatment centers, but there may be more individuals being cared for by hematologists and primary care doctors because VWD is a common and usually mild bleeding disorder.
- Sickle Cell Disease: An inherited blood disorder, sickle cell disease affects the shape and function of red blood cells. In this disease, the red blood cells are shaped like sickles, or crescent moons, rather than being round. The sickle-shaped cells can prevent the blood from flowing properly in the body and can lead organ dysfunction and to severe pain. The risk of developing serious complications in the brain, lungs and heart increases with age. About 2,000 children in the United States are born with sickle cell disease each year.
- Thrombosis: When blood clots form abnormally within blood vessels, they can obstruct blood flow, a condition called thrombosis. If the clot in a vein travels to the lungs, it is called a pulmonary embolism—the sudden blocking of an artery to the lung. Combined, deep vein thrombosis (blood clot in a leg vein or less commonly, an arm vein) and pulmonary embolism are referred to as venous thromboembolism, which is diagnosed in about two million Americans each year, claiming more than 100,000 lives annually. Hematologists will work together with pulmonary physicians, interventional radiologist, vascular surgeons, and others in developing a treatment plan.
- Anemia: When a deficiency of oxygen in the blood is caused by a lack of healthy blood cells, a person has anemia. Anemia, has many types and causes; can be chronic or acute; and symptoms can be mild to severe. The main symptom of anemia is fatigue. Per the CDC, 2.8 million Americans are diagnosed with anemia per year. Anemia, due to low iron, is one very common cause of anemia worldwide. This can be due to excessive bleeding such as from heavy menstrual bleeding, bleeding from the stomach or intestine, or not enough iron in the diet. Iron deficiency is common in young children and menstruating women as well as in those who are under-nourished.
While there are no cures for most bleeding disorders, Yale hematologists work across many programs to care for patients with benign blood conditions. Over the past 35 years, the Yale Hemophilia Treatment Center has provided excellence in hemophilia care through a multidisciplinary approach, utilizing the expertise of nurses, physical therapists, social workers, dentists, orthopedic surgeons, advanced practice providers and physicians, and serves as a regional treatment center for patients with bleeding disorders. It is one of eight comprehensive hemophilia treatment centers in New England.
Yale is also a leader in research, participating in the CDC’s national hemophilia clinical research study, the Registry for Bleeding Disorders Surveillance, which aims to track longitudinal complications and quality of life in individuals with hemophilia and other bleeding and clotting disorders.
The Section of Hematology is committed to advancing the science and practice of hematology by understanding the molecular basis of disease, and translating basic discoveries to the clinic. To learn more about their work, visit Hematology.