If your baby has been diagnosed with fetal and neonatal alloimmune thrombocytopenia (FNAIT), your doctor may recommend a platelet transfusion, which is a treatment option used to raise platelet count and prevent potential complications like internal bleeding.
While transfusion with both HPA-matched platelets or random donor transfusions can help, it’s important to understand the differences and why matched platelets are preferable.
Why platelet transfusions are necessary in FNAIT
FNAIT is a rare immune disorder that occurs during pregnancy when the mother’s immune cells recognize her baby’s platelets (fragments of blood cells responsible for blood clotting) as foreign. Her immune system develops antibodies that attack the baby’s platelets, resulting in a severely low platelet count, or thrombocytopenia. This increases the risk of internal bleeding, which can be serious if it occurs in major organs like the brain.
Learn more about FNAIT treatment and care
FNAIT typically occurs because the baby inherited a human platelet antigen (HPA) from their father that the mother does not have. One of the ways to counter this is through platelet transfusions, which gives the baby new platelets to replace the ones that were destroyed.
Platelets used in the transfusion may be either HPA-matched or random donor platelets.
HPA-matched platelets vs random donor platelets
Random donor platelets are collected from people without screening for specific HPA types. Because of the lack of selection process, there’s a chance this could result in the donor platelets containing the same antigen that triggered the mother’s immune response in the first place. Her immune system may then attack the donor platelets just as aggressively as the baby’s platelets.
HPA-matched platelets come from donors who don’t have the specific antigen that the mother’s immune system is reacting to. Because these platelets don’t contain the “target,” they’re less likely to be attacked by the mother’s immune cells and are more likely to restore a normal platelet level in the baby.
Studies have found that using HPA-matched platelets lead to higher platelet counts that stay in the baby’s bloodstream longer compared to random donor platelets. As a result, HPA-matched platelets are considered to be optimal and generally recommended when treating FNAIT.
Random donor platelets can still be effective
Sometimes, HPA-matched platelets may not be immediately available. If this is the case, it’s recommended that the procedure not be delayed and to use random donor platelets.
Research shows that while HPA-matched platelets are optimal, random donor platelets often provide enough benefits to increase the baby’s platelet count.
If HPA-matched platelets become available once the treatment course has started, they can be used instead of the remaining random donor platelets.
If you have any questions or concerns about platelet transfusion for FNAIT, talk to your doctor.
Sign up here to get the latest news, perspectives, and information about FNAIT sent directly to your inbox. Registration is free and only takes a minute.
