Familial Hyperbilirubinemia in ABO-Incompatible Neonates

To the Editor.—

We read with interest the report of Sarici et al¹ on their success in predicting subsequent hyperbilirubinemia by performing first- day serum bilirubin determinations in ABO-incompatible neonates. Although the incidence of hyperbilirubinemia of 21.3% is perhaps not surprising in an ABO-incompatible cohort, the authors also note that, in a previous study in the same population group, the incidence of hyperbilirubinemia in their general neonatal population was as high as 12.05%.² Of note was the observation that a significant risk factor for hyperbilirubinemia among the ABO-incompatible neonates was a sibling with neonatal jaundice.

It is surprising that although in both studies glucose-6-phosphate dehydrogenase (G-6-PD) deficiency was screened for routinely, the results of this screening were not provided. G-6-PD deficiency may result in an incidence of neonatal hyperbilirubinemia several times higher that of G-6-PD-normal counterparts.³ Furthermore, G-6-PD deficiency may result in rates of neonatal bilirubin production …