![San Diego, CA - December 22: Registered Nurse Lisa Hayes prepares a premature baby for a blood transfusion in the NICU department of Rady Children's Hospital in San Diego, CA on Thursday, Dec. 22, 2022. Newborns will be among the most threatened groups if an anticipated shortage of rare blood types materializes. (Adriana Heldiz / The San Diego Union-Tribune) San Diego, CA - December 22: Registered Nurse Lisa Hayes prepares a premature baby for a blood transfusion in the NICU department of Rady Children's Hospital in San Diego, CA on Thursday, Dec. 22, 2022. Newborns will be among the most threatened groups if an anticipated shortage of rare blood types materializes. (Adriana Heldiz / The San Diego Union-Tribune)](https://www.sandiegouniontribune.com/wp-content/uploads/migration/2023/10/25/00000185-3bd0-dcff-a5c7-7bd0b0310000.jpg?w=535)
Thornburg, M.D., is a professor of pediatrics at UC San Diego and director of the Hemophilia and Thrombosis Treatment Center at Rady Children’s Hospital. She has cared for children with inherited blood disorders and conducted clinical trials for over 20 years. She lives in La Jolla.
Every day, I treat kids at Rady Children’s Hospital who are living with blood diseases, including inherited red blood cell disorders. Many of these children have already undergone hundreds of blood transfusions in their lives. They need the best possible blood matches for transfusions, ideally from donors with similar backgrounds, to survive and thrive into adulthood. That’s why we are launching a clinical trial in partnership with San Diego Blood Bank that aims to expand the use of closely matched Precision Blood.
What’s wrong with the current standard of blood transfusions?
Rigorous donor screenings and safety precautions, as well as decades of research into blood typing, have ensured that the 18 million blood transfusions that happen each year in America are highly successful.
But for some people who require multiple transfusions over their lives, dangerous immune reactions called alloimmunization, can occur. This is when the body thinks a protein on transfused red blood cells is foreign, develops antibodies and attacks them. When people have alloimmunization, it is harder to find matched blood and the matching process takes longer, delaying critical treatment. The risk of alloimmunization starts with a patient’s first transfusion, so any child who needs regular blood transfusions should get the best possible match from the start.
My patients with sickle cell anemia and thalassemia, which are inherited blood disorders, are most often Black, Hispanic/Latino or Asian/Pacific Islander. They often require regular transfusions to treat anemia and prevent complications such as pain, fatigue, weakness, poor growth, blood clots, organ failure and stroke. Regular blood transfusions have saved and improved the lives of many of these children — but the more transfusions they receive, the higher their risk of alloimmunization due to less-than-optimal blood matches.
Precision Blood is a promising tool to prevent alloimmunization and its negative effects in our young patients by making their blood supply safer and more durable. The initiative draws from recent research that shows the existence of 30 blood groups with more than 300 antigens that impact how well two peoples’ blood usage match — and race and ethnicity play a key role in these genetic markers. Like precision medicine treatments, which aim to provide the right medication to the right person at the right time, Precision Blood treatments aim to provide blood transfusions with blood that is as close to a match as possible using these newer standards.
Starting chronically transfused patients with the right blood matches as early as possible is key to the best outcomes. The majority of children with sickle cell anemia and thalassemia in San Diego County get care at Rady Children’s, a top 10 children’s hospital in the U.S. This is why we’re focusing our efforts on the kids at Rady Children’s.
Children with inherited anemias who receive regular blood transfusions at Rady Children’s will be eligible to participate in this clinical trial, which aims to confirm if Precision Blood should be applied for all transfusions in this patient population. Outcomes will be compared between participants who have standard of care matching versus those who have Precision Blood matching. We expect those with Precision Blood matching will have more blood cell antigens matched in each unit of blood, less alloimmunization and fewer complications overall.
In order for Precision Blood to have an optimal effect, we need more racially diverse blood donors to supply us with the lifesaving blood products our transfusion patients depend on. Less than 3 percent of the eligible U.S. population donates blood each year. In San Diego County, 63 percent of our blood donors are White (and this number is closer to 75 percent nationwide), whereas patients with sickle cell or thalassemia are predominantly Black or of African, Southeast Asian, South Asian, Middle Eastern, African or Mediterranean descent.
I urge anyone who is eligible to donate blood and/or participate in a blood drive with San Diego Blood Bank, our partner in this Precision Blood clinical trial. Encourage other people in your community to donate, too. If your community is typically underrepresented amongst blood donors, your donation will mean even more. Every donation counts, and young lives depend on you.