Haem degradation products in the feces (rneconiurn and stools) of jaundiced and normal newborn infants

Abstract

Summary Background: Meconium (the first stool passed by the newborn infant), accumulates continuously in the fetal intestine. Analysis of this postnatally excreted material i.e. meconium yields important information of intrauterine metabolism. Meconium has a characteristic black-green color whereas the stools of the neonate are pale yellow due to high intake of milk. The pale golden yellow stools therefore gradually replace the black green color as milk is added to the newborn infants diet. Data on total bilirubin in faeces obtained by diazo method are available; however these methods do no1 allow individual bilirubins to be studied quantitatively. Objectives: The aim of this study was to quantify the total bilirubin in the first meconium of the newborn infant. To relate the bilirubrn in rneconium with the clinical parameters and neurological outcome. The study identified haem degradation product (bilirubin) in the meconium of the newborn infant admitted at the neonatal care of CHK. Methods: 45 newborn infants of various gestational ages were included in this study. Random sampling from the neonatal unit was done. 2 newborns being included every week 37 newborns were finally included as 8 expired before passage of meconium. Meconiurn was collected carefully and stored at -- 20 C, protected by aluminium foil. Samples were defrosted. Vortex mixed with equal amount of dimethyl-sulfoxide, centrifuged, and submitted to analysis by Hiqh-pressure liquid chromatography using newly developed methods. Results: Unconjugated Bilirubin-IXα and Bilirubin-IXβ were identified and quantitative estimation of Bilirubin Ixα was done. Bilirubin IXβ was the predominant pigment greater than 50% of the total, in the first meconium of the newborn. The amount of bilirubin excreted in the meconiurn was 29.2 -- 90.8 rng (0.051 – 0.155 µrnol) per sample of meconium passed. The amount was 9.7 mg / Kg of body weight in the term newborn and 12 mg / kg in the preterm. In some newborns (2 samples) the amount of bilirubin excretion was increased to 20 mg Conclusion: The estimation of bilirubin can easily be done quantatively in both HEJ / SIUT, both of which have the personnel and facilities like the HPL.C. This procedure highlights the importance of bilirubin as a perinatal marker and reflects fetal development in terms of maturity. As the preterm tends to pass more bilirubin and of the IX beta variety. Key words: Pakistani newborn, Bilirubin, HPLC