Neonatal alloimmune thrombocytopenia: two different neonatal manifestations of the same disease


  • Miguel P. Pereira Department of Pediatrics and Neonatology, CUF Descobertas Hospital, Lisbon, Portugal
  • Marta Pinto Department of Obstetrics and Gynecology, CHUC, Coimbra, Portugal
  • Mafalda Lucas Department of Pediatrics and Neonatology, CUF Descobertas Hospital, Lisbon, Portugal
  • Ana P. Domingues Department of Obstetrics and Gynecology, CUF Descobertas Hospital, Lisbon, Portugal
  • Cristina Matos Department of Pediatrics and Neonatology, CUF Descobertas Hospital, Lisbon, Portugal
  • Jorge Lima 3Department of Obstetrics and Gynecology, CUF Descobertas Hospital, Lisbon, Portugal 4Comprehensive Health Research Centre, CEDOC, NOVA Medical School, Universidade Nova de Lisboa, Lisbon, Portugal



Neonatal alloimmune thrombocytopenia, Neonatal stroke, Prenatal screening, Antenatal management


Fetal and neonatal alloimmune thrombocytopenia is a rare disorder in which maternal alloantibodies cross the placenta and cause fetal thrombocytopenia. Most cases are mild but can be potentially fatal if there is an intracranial haemorrhage. Usually, the mother is asymptomatic during pregnancy and no screening is routinely recommended unless there is obstetric or family history. After birth, prompt identification is crucial so that the newborn is closely monitored and treatment is given, if needed, to prevent serious complications. In this article we present two clinical cases of fetal and neonatal alloimmune thrombocytopenia in first-born children, after uneventful pregnancies, with different outcomes and discuss the obstetric management and follow-up in future pregnancies.


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