Verzögerte intrakranielle Blutung bei einem Neugeborenen mit Alloimmunthrombozytopenie nach seriellen pränatalen Thrombozytentransfusionen

Abstract

Delayed Intracranial Hemorrhage in a Newborn with Alloimmune Thrombocytopenia after Intensive Prenatal Treatment with Serial Platelet Transfusions Background: Fetal alloimmune thrombocytopenia (FAIT) is caused by maternal immunization against a fetal platelet antigen, most frequently HPA-1a (Zw^a, Pl^A1), and subsequent transplacental transfer of maternal IgG antibodies into the fetal circulation. The fetus and the neonate are threatened by severe bleeding, particularly intracranial hemorrhage (ICH), which occurs in 10–20% of all cases. We describe a case of FAIT due to immunization against HPA-1a. Patients, Materials and Methods: At the beginning of pregnancy, the previously diagnosed HPA-1a antibody was confirmed by monoclonal antibody-specific immobilization of platelet antigen (MAIPA). Fetal blood specimens were obtained by umbilical venipuncture. Fetal platelet counting and umbilical blood sampling, first in the 22nd week of gestation, were combined with intrauterine platelet transfusion of HPA-1a-negative platelet concentrates of maternal or high-dose donor platelet concentrates. The thrombocytopenic fetus was treated by nearly weekly intrauterine platelet transfusions of maternal or donor platelet concentrates and delivered by caesarean section in the 35th week of gestation. Results: Our observations suggest that frequent platelet transfusions in short intervals may be necessary to increase platelet counts in thrombocytopenic fetuses. The platelet count at birth was 145,000/µl. The newborn did not show any signs of cutaneous bleeding. Postpartal ultrasonic examination of the child’s head revealed no signs of ICH. The platelet counts were examined daily during a 14-day period. Platelet counts reached a nadir of 70,000/µl at day 4. The child was discharged at day 14 with 150,000 platelets/µl and without any hemorrhagic symptoms. Neurologic examination at the age of 6 months revealed subtle signs of a developmental disturbance. Upon ultrasonic examination a parieto-occipital posthemorragic cyst was detected. Conclusion: Delayed ICH may occur in newborns with FAIT. It remains to be elucidated whether this complication is a specific problem in children who had been treated with serial intrauterine platelet transfusions for FAIT. However, for the early recognition of such delayed ICH, short-term postpartal examinations during the first months of life are necessary.