Maternal Anti-PF4 Antibodies as Cause of Neonatal Stroke

This correspondence reports a case of neonatal stroke caused by transplacentally transferred maternal anti–platelet factor 4 (PF4) antibodies. A female neonate developed seizures and was diagnosed with cerebral venous sinus thrombosis, thrombocytopenia, and arterial infarctions. The mother had a history of thrombophilia and monoclonal gammopathy. Laboratory evaluation confirmed the presence of platelet-activating anti-PF4 antibodies in both mother and child, consistent with a VITT-like immune response. The case suggests a novel mechanism of neonatal stroke and highlights the importance of anti-PF4 antibody screening in pregnant women with thrombotic histories.

This correspondence reports a case of neonatal stroke caused by transplacentally transferred maternal anti–platelet factor 4 (PF4) antibodies. A female neonate developed seizures and was diagnosed with cerebral venous sinus thrombosis, thrombocytopenia, and arterial infarctions. The mother had a history of thrombophilia and monoclonal gammopathy. Laboratory evaluation confirmed the presence of platelet-activating anti-PF4 antibodies in both mother and child, consistent with a VITT-like immune response. The case suggests a novel mechanism of neonatal stroke and highlights the importance of anti-PF4 antibody screening in pregnant women with thrombotic histories.