Elevated bilirubin in newborns with Down syndrome has been previously reported but the frequency has not been well-described. A recent retrospective report (TM Bahr J Pediatr 2020; 219; 140-5) compared 357 neonates with Down syndrome to 377,368 controls.
- Compared with control subjects, neonates with Down syndrome had 4.7 times the risk of having an initial total serum bilirubin exceeding the 95th percentile (23.5% vs 5.0%), 8.9 times the need for phototherapy (62.2% vs 7.0%) and 3.6 times the readmission rate for jaundice (17.4 vs 4.8 per 1000 live births).
The authors note that the basis for the increased risk of hyperbilirubinemia may be early hemolysis related to “neocytolysis” which is due to destruction of RBCs following a change from low to high oxygen exposure. Other factors could include slower bilirubin conjugation/elimination and poor feeding.
My take: This study indicates that infants with Down syndrome have a substantial risk of hyperbilirubinemia. And, while you are checking a bilirubin, it is worthwhile to obtain a direct bilirubin as cholestasis is increased in infants with Down syndrome too; the latter is often transient and/or associated with other organ involvement.
Related blog post: Neonatal cholestasis and Down syndrome