Urinary Melatonin Metabolite in Premature Infants with Extremely and Very Low Birth Weight

Abstract

The aim. Determination of daily urinary 6-sulfatoxymelatonin in premature infants with extremely and very low birth weight. Materials and methods. A non-invasive, descriptive, single-centered study involving data of 96 premature infants with weight less than 1500 g : 46 infants with extremely and 50 infants with very low birth weight. The study included a detailed scrutiny of history and objective examinations, data from medical records, anthropometric measurements, and daily urine collection. Determination of 6 - SM in the 24-hours urine collection from premature infants was performed by enzyme immunoassay on the analyzer “Labline-90” (Austria) using a commercial test system manufactured by “LDR” (LABOR DIAGNOSTIKA NORD GmbH & Co.KG, Germany) according to the provided instruction. 166 portions of urine were collected during the examination in time intervals: 96 portions of urine in premature infants at 1st day of life and 70 portions at 10th – 14th day of life. Results. Ante- and intranatal periods for the infants enrolled in the study were characterized by conditions: premature rupture of membranes 37 (38.5%), multiple pregnancy 16 (16.6%), preeclampsia 15 (15.6%), isthmic-cervical insufficiency 11 (11.5%), placental abruption 8 (8.3%), extra corporal fertilization 5 (5.2%), chorioamnionitis 4 (4.2%); caesarean section urgent 33 (34.4%) and planned 24 (25.0%). There was no any significant difference in frequency of ante – and intranatal pathology between ELBW and VLBW. Antenatal administration of corticosteroids for reduce the severity of neonatal respiratory distress syndrome occurred in all mothers of infants enrolled in the study. There was significant low urinary 6-sulfatoxymelatonin level in extremely low birth weight infants (median 120.0 pg /mL) on the 1st day of life compared with very low birth weight (median 348.5 pg / mL). There was no difference at 10 – 14th days. The predictive level of lethal outcome in infants with extremely low birth weight is ≤ 84 pg / mL with sensitivity 84.62% and specificity 70.0%. Conclusion. In infants with extremely and very low birth weight the determining the urinary 6-sulfatoxymelatonin is a non-invasive method. The significant decrease level of urinary 6-sulfatoxymelatonin in infants with extremely low birth weight on the first day of life was found. The measurement of urinary 6-sulfatoxymelatonin will allow to establish the prediction of perinatal outcomes. Its levels <87 pg / mL is associated with lethal outcomes. Authors speculate than it will the way for future supplement of melatonin to premature infants and study of its effect on perinatal outcomes