Evaluation of Serum Zinc Levels in Hyperbilirubinemic Neonates Before and After Phototherapy

Abstract

BackgroundThe existing therapeutic methods for neonatal jaundice are costly, time-consuming and potentially risky. Zinc salts can reduce phototherapy duration by precipitating unconjugated bilirubin in the intestine (bilirubin and zinc can form a complex in physiologic pH); however, zinc toxicity is an issue that must be considered since theoretically bilirubin reduction by phototherapy may increase serum zinc levels, making additional zinc supplementation the potential cause of zinc toxicity.ObjectivesSo, our purpose was evaluating the serum zinc level alterations before and after phototherapy, in hyperbilirubinemic newborns.Materials and MethodsA prospective cohort study was performed at the children’s medical center of Tehran University of Medical Sciences from 2012 to 2014. Healthy, full-term exclusively breast fed newborns with non-hemolytic jaundice were enrolled in the study. Participants were divided into two groups based on serum bilirubin levels (TSB < 18 mg/dL and TSB ≥ 18 mg/dL) at admission. Pre- and post-phototherapy total serum zinc level was measured before and 12 - 24 hours after termination of phototherapy.ResultsPhototherapy was associated with a significant increase in the serum zinc level in neonates with severe hyperbilirubinemia (TSB ≥ 18 mg/dL) but not in those with mild-moderate hyperbilirubinemia (TSB < 18 mg/dL). In addition, phototherapy caused a significant increase in the rate of zinc with potentially toxic levels (zinc > 200) in only neonates with severe hyperbilirubinemia.ConclusionsPhototherapy increases serum zinc level by reducing bilirubin level so that additional supplementation of this element can lead potentially to zinc toxicity.

Effect of Phototherapy on Serum Zinc Level in Neonatal Jaundice

“…In addition, our analysis showed that the duration of phototherapy was 2.4 ± 0.5 days, which is similar to Mosayebi et al (14) and Saravanan and Raghuram (15) where the duration was 2.4 ± 0.6 days in both studies.…”

“…Concerning the type of phototherapy, there were a statistically significant higher proportion of patients who underwent intensive phototherapy (59% intensive versus 41% conventional phototherapy), which is coincident with Mosayebi et al (14) who showed that 51% underwent intensive phototherapy. The current evidence indicates that aggressive implementation of phototherapy results in a clinically significant rate of bilirubin decrease, and that neonate with severe hyperbilirubinemia needs more excessive photo to reduce the need for exchange transfusion and possibly reduce the severity of bilirubin neurotoxicity (18) .…”

“…Previous reports have shown that the average age of admission was approximately three and half days in patients with severe hyperbilirubinemia (13) . Mosayebi et al (14) in their study of serum zinc levels in hyperbilirubinemic neonates before and after phototherapy showed that the average age of admission was 5.7 ± 2.9 days in patients with severe hyperbilirubinemia.…”

Effect of Phototherapy on Zinc Status in Term Neonates With Indirect Hyperbilirubinemia

“…One cohort study revealed that zinc and bilirubin levels are inversely correlated in neonates with marked hyperbilirubinemia. Additionally, phototherapy caused a marked elevation in the rates of neonates with potentially toxic zinc levels (zinc > 200 µgm/dl) among neonates with marked hyperbilirubinemia, while no significant change was reported amongst those with mild to moderate cases (Mosayebi et al, 2016).…”

Atualizações sobre fototerapia em neonatos a termo e pré-termo com icterícia não-hemolítica

“…Outros efeitos mais ambíguos na literatura são: nevos; danos ao DNA e ao sistema imunológico, convulsões, epilepsia, estresse oxidativo, e câncer. A gravidade e a incidência destes variam muito com a severidade da icterícia, idade, peso, e até mesmo sexo do neonato (5,9,(30)(31)(32)(33)(34)(35)(36).…”