Study of relationship between total Magnesium and total bilirubin levels in neonate's sera before and after phototherapy

Binding indirect bilirubin to neuronal membranes receptors such as N-methyl-D-aspartate (NMDA) causes permanent injuries. Magnesium (Mg) ion is proposed to be one of the most important antagonistic regulators of this receptor. We studied relationship between serum levels of total magnesium and total bilirubin before and after phototherapy in term neonates to find new therapeutic and management techniques and the best time for discharge. In this semi-experimental, we evaluated icteric neonates whom admitted to Zahedan Imam Ali hospital from March 2009 to March2010. Neonates with symptoms in favor of sepsis, hemolysis and with administration of magnesium sulfate in their mother were not included in this study. The collected data were analyzed by paired sample t-test, and Analysis of Variance via SPSS software. 90 patients with icterus were studied. Hyperbillirubinemia frequencies before phototherapy included Mild (14-16mg/dl) 28.8%, Moderate (16-18) 33.3% and, Severe (≥18 (37.7% Hyperbillirubinemia. Means of billirubin levels were 18.38mg/dl before and 12.99 mg/dl after phototherapy (p<0.0001 T= 19.44). Mg levels were also 2.669 before phototherapy, and 2.03 afterwards (p< 0.001 T= 5. 13). Levels of magnesium in neonates with severe hyperbilirubinemia were higher than mild hyperbilirubinemia group (p= 0.03) before phototherapy. ANOVA- test results showed significant differences between total magnesium levels just in severe hyperbilirubinemia and bilirubin below 14 groups after phototherapy (p= 0.016) respectively. There was a correlation between total magnesium and total bilirubin levels before (r= 0.315, p= 0.001) and after phototherapy (r= 0.314 p = 0.004). It is concluded that phototherapy can decline total magnesium and total bilirubin serum levels in the same direction.