Comparison of transcutaneous bilirubin with serum bilirubin measurements in neonates at tertiary care center in western part of India

Background: Noninvasive transcutaneous bilirubin measurement is an attractive option for jaundice evaluation in newborns. But variable accuracy had been reported in different studies. The aim of the study was to find out the correlation and agreement between TcB and TSB measurements in neonates.Methods: Prospective analytic study carried out in neonatal unit of tertiary care center. Newborns up to 10th postnatal DOL with visually found jaundice were enrolled in study. TcB was measured over forehead with Dragor JM 103 device. Simultaneous TSB measurements were done for all readings. Pearson’s correlation coefficient calculation and Bland Altaman analysis were done. ROC curve of mean TcB at different TSB level were constructed.Results: Total 160 newborns with male: Female ratios of 1.3:1 were enrolled. Mean values: gestational age 38.23±2.01; birth weight 2.403±0.61; age in hour at first reading 83.76±26.62; TSB11.65±4.58 mg/dl and TcB 11.73±3.53 mg/dl. A strong, positive and significant correlation was found between TcB and TSB measurements (r=0.836, r2=0.69, p <0.001). The average error in evaluating hyperbilirubinemia with TcB as compared to TSB was 0.856 with limits of agreement between -3.41 to +5.48. The AUOC at three TSB levels (>10mg/dl, >12 mg/dl, >15 mg/dl) of TcB were 0.899, 0.937 and 0.963 respectively. ROC analysis showed good sensitivity for all. Specificity was found to fall with increasing TSB concentration.Conclusions: In our study TcB correlated well with TSB measurements and showed good sensitivity and satisfactory specificity, thus validating its use as a screening tool for evaluation of jaundice in newborns.