In fetal and neonatal alloimmune thrombocytopenia (FNAIT), platelet destruction in newborns can be described as acute or chronic, and each type has its own challenges.
Acute disease, also known as severe thrombocytopenia, is sudden and more often requires rapid medical intervention to treat bleeding and avoid dangerous consequences. Chronic thrombocytopenia occurs more slowly and consistently, with less severe bleeding.
Close monitoring of babies suspected of FNAIT is essential to differentiating between the two types and ensuring the most appropriate medical approach.
What is FNAIT?
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a rare but serious condition in which a pregnant mother’s immune system produces antibodies against the platelets of her fetus. This occurs when a fetus inherits platelet antigens from the father that are not compatible with the mother, typically involving a protein called human platelet antigen (HPA). The mother’s immune system recognizes the fetal platelets as foreign, attacking and destroying them, leading to low platelet levels (thrombocytopenia) in the fetus or newborn.
What is acute platelet destruction?
Acute platelet destruction becomes evident in newborns when there is a rapid and intense onset of FNAIT-related symptoms. Platelet levels can drop suddenly post-delivery, when the newborn is still experiencing the effects of a high level of maternal antibodies.
It leads to platelets being destroyed more quickly, with the risk of severe bleeding and severe symptoms, including intracranial hemorrhage (ICH).
Learn more about FNAIT signs and symptoms
Treating acute platelet destruction in newborns and fetuses
Acute thrombocytopenia symptoms include a very low platelet count on the first post-delivery blood test, unexplained bleeding, bruising, skin discoloration called purpura or petechiae, cephalohematoma and ICH. The newborn may also exhibit lethargy, fussiness and poor feeding.
Acute platelet destruction is treated with urgent platelet transfusions, intravenous immunoglobulin (IVIG) with or without steroids and close monitoring through imaging to guide treatment. Infants should be treated as quickly as possible to ensure the best outcomes.
What is chronic platelet destruction in FNAIT?
Chronic platelet destruction is a milder and more consistent form of FNAIT, characterized by low platelet levels in the newborn, which can persist for days or weeks. Newborn platelet levels will improve as the maternal antibodies in the newborn’s blood start to dissipate.
In most cases, chronic platelet destruction does not result in long-term consequences for the infant.
Treating chronic platelet destruction in newborns suspected of FNAIT
The progressive drop in platelet levels over time or platelet levels that stay consistently low are key to identifying chronic platelet destruction. Associated symptoms can include unexplained bleeding, bruising, purpura and petechiae and a low platelet count. However, unlike the acute version, the newborn may seem otherwise healthy.
When treating chronic platelet destruction, the focus is on long-term protection. Platelet transfusions will be administered until platelet levels begin to rise. Close monitoring of symptoms and blood tests to track the evolution of platelet counts can help guide treatment. Ongoing care following discharge from the hospital can be continued on an outpatient basis until platelet levels return to normal levels.
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.
