HPA-1 carrier status and thrombocytopenia in preterm infants with a birth weight below 1500 grams.

OBJECTIVE

In cohorts of infants with proven neonatal alloimmune thrombocytopenia (NAIT) an unusual high rate of preterm infants has been reported, raising the question of whether NAIT contributes to the high rate of intracranial hemorrhage in preterm infants.

METHODS

We genotyped the HPA-1-allele in a large cohort of term (n = 205) and very low birth weight infants (VLBW-infants, n = 299) with polymerase-chain-reaction and restriction enzyme digestion.

RESULTS

HPA-1a/b is the only fetal HPA-1-genotype in which alloimmunization and NAIT could occur. Genotype distribution did not differ between term and VLBW-infants (p = 0.26). Furthermore, neither HPA-1a/b genotype nor platelet count at birth were of significant prognostic value in predicting subsequent intracranial haemorrhage or death in VLBW-infants (p = 0.93 and p = 0.19 respectively).

CONCLUSION

Our data did not support the hypothesis that routine screening of preterm infants or their mothers for HPA-1-genotype is of additional value in the care of these infants.