Cord Blood Albumin and Cord Blood Bilirubin in Early Detection of Neonatal Hyperbilirubinemia

Introduction: During the neonatal period, metabolism of bilirubin is in transition from the fetal stage to the adult stage1. Uridine diphosphoglucuronyl transferase (UDPGT), an important liver enzyme for conjugation and excretion of bilirubin, is detectable at 18 – 20 weeks of gestation. UDPGT levels in full term neonates are usually less than 0.1% of adult values. Adult value of this enzyme activity is demonstrable only by 6–14 weeks of postnatal life2. Synthesis of albumin appears at approximately the 7th-8th wk. in the human fetus and increases in inverse proportion to that of α-fetoprotein. Albumin concentrations are low in a neonate (∼2.5 g/dL), reaching adult levels (∼3.5 g/dL) after several months.3 Albumin has been described as “the body’s tramp steamer, shuttling cargo of various kinds between ports of call”. Its load includes bilirubin, free fatty acids, calcium, etc.4 Bilirubin binds to albumin in an equimolar ratio. Free bilirubin is anticipated when the bilirubintoalbumin (B: A) ratio is > 0.8. Around 8.5mg of bilirubin will bind tightly to 1 g of albumin.3 Neonatal Hyperbilirubinemia (NH) is commonest abnormal physical finding during the first week of life. Serum bilirubin over 15 mg% is found in 3% of normal term neonates.3 Neonatal Hyperbilirubinemia (NH) is the most common cause for readmission during the early neonatal period (6.5%).5 American Academy of Pediatrics (AAP) recommends that neonate discharged within 48 hours should have a follow-up visit after 48 to 72 hours for any significant jaundice and other problems.6 This recommendation is not appropriate for our country due to poor access to health care facility. NH which may be over looked or delay in recognition by parents, because lack of knowledge. Concern of pediatrician regarding the early discharge is bilirubin encephalopathy sequel occurring in healthy term infants even without hemolysis. 7, 8 Physical examination is not a reliable measure of the serum bilirubin. By predicting the neonates at risk for significant NH early at birth, we can design and implement the follow-up programme in these risk groups, cost effectively. There are studies to predict NH by measuring cord albumin and cord bilirubin individually. The present study is carried out comparing these two variables. Hence the objectives of the study are: Comparing Cord Serum Albumin level (CSA) with Cord Serum Bilirubin (CSB) in predicting neonatal hyperbilirubinemia and to know the sensitivity, specificity, Positive predictive value and negative predictive value of CSA and CSB in predicting neonatal jaundice in term neonates. Objective: 1. Comparing Cord Serum Albumin level (CSA) with Cord Serum Bilirubin (CSB) in predicting neonatal hyperbilirubinemia. 2. To know the sensitivity, specificity, Positive predictive value and negative predictive value of CSA and CSB in predicting neonatal jaundice in term neonates. Method: Prospective study was performed on 750 healthy term neonates. Relevant maternal history is collected. Cord blood was collected from the healthy term neonates at birth, CSA and CSB measured. Neonate was assessed clinically every day. Total Serum Bilirubin (TSB) and blood group were assessed in neonate during 72-96 hours of life. TSB value ≥15mg/dl is considered Neonatal Hyperbilirubinemia (NH) which requires intervention like phototherapy (PT) or Exchange transfusion (ExT). Result: Study cohort is grouped in Group 1 and group 2 based on Cord Serum Albumin level ≤2.5g/dl and ≥2.5g/dl, respectively. Based on CSB, study cohort divided into neonates with CSB ≤ 4.5mg/dl and CSB ≥ 4.5mg/dl. Statistical analysis done for correlation of CSA and CSB with NH. Statistical significance is seen for both CSA and CSB. Conclusion: Both CSA and CSB are equally effective in predicting NH at birth. These study variables can be considered as neonatal screening tool for NH for term neonates.