Effect of Phototherapy Treatment on Urinary Calcium Excretion in Neonates with Jaundice in Zahedan, Iran

Background: One of the recognized symptoms of phototherapy in neonates is hypocalcemia and hypercalciuria, and its etiology has not been identified yet. The present study investigated the recurrence of hypercalciuria among neonates with jaundice treated with phototherapy. Methods: This cross-sectional diagnostic examination was conducted on 100 newborns with jaundice treated with phototherapy in Ali-ibn-Abi-Talib hospital in Zahedan, Iran, during 2013 and 2014. In the present study, the subjects were collected in an accessible way after agreement and considering exclusion criteria. Calcium and creatinine (Ca/Cr) proportion in urinary tests of the neonates was estimated at the baseline and 24 h after the onset of phototherapy. The information was analyzed utilizing paired t-test. Results: The mean of gestational age was 38.5±2.5 weeks. Out of 100 cases, 53 newborns (53%) were male and 47 (47%) were female. The mean scores of birth weight was 2.52±0.59 kg and neonatal serum bilirubin level was 16.5±0.92 mg/dl. Ca/Cr ratios in neonates with jaundice were 0.28±0.21 and 0.40±0.34 before and after the phototherapy, respectively. Regarding that, the increase in Ca/Cr ratio was statistically significant (P 0.001). Hypercalciuria was not observed in the neonates before the phototherapy; however, it was noticed in 13 neonates after the phototherapy. Ca/Cr ratios in neonates with hypercalciuria and other newborns were 1.16±0.19 and 0.29±0.18, respectively. Furthermore, the difference between the two groups was statistically significant (P 0.001). Conclusion: Based on the results of this study, it was suggested that the neonates undergoing the phototherapy were at risk of hypercalciuria and the increased amount of urinary calcium excretion by means of phototherapy.