Correlation between Prolonged Hyperbilirubinemia and Serum Zinc Level in Term Neonates

Prolonged hyperbilirubinemia is defined as jaundice persisting more than two and three weeks of life in term and preterm neonates, respectively. In total, 15-40% of jaundiced neonates became prolonged. The most common causes of prolonged hyperbilirubinemia are breastfeeding, infection, hypothyroidism, and continued hemolysis. Given the fact that no study was conducted on the association between the serums zinc level and prolonged hyperbilirubinemia, this study aimed to compare the healthy neonates with newborns suffering from prolonged hyperbilirubinemia in terms of serum zinc level.

This cross-sectional analytical descriptive study with a control group included all neonates who had a history of hospital admission and phototherapy due to hyperbilirubinemia at Amirkola Children’s Hospital, Babol, Iran. After discharge, on the 14th day of birth, all neonates followed up at the outpatient clinic. The serum bilirubin was checked and the neonates were assigned into the case (with prolonged hyperbilirubinemia) and control (without prolonged hyperbilirubinemia) groups. Both groups were matched regarding confounding factors. Serum zinc level was measured using the colorimetric method and the two groups were compared in this regard.

In total, 60 neonates in the case (n=30) and control (n=30) groups were investigated in this study. The serum zinc levels in the case and control groups were 83.7±35.35 and 92.73±38.13 μg/dl, respectively. There was no significant difference between the two groups in terms of the serum zinc level (P=0.34).

There is no statistically significant correlation between the serum zinc level and prolonged hyperbilirubinemia in term neonates who had been treated with phototherapy.