A comparative study of transcutaneous bilirubin measurement and total serum bilirubin in neonatal hyperbilirubinemia

Objectives: (1) To compare the accuracy of TCB with TSB in neonates with hyperbilirubinemia. (2) To compare the accuracy of TCB levels with conventional TSB levels. Material and Methods: In this cross-sectional study, a total of 189 neonates were diagnosed with jaundice. The study was performed in the Department of Paediatrics, SNR District Hospital, Kolar, Karnataka, from August 2023 to November 2024. TCB and TSB levels were measured before phototherapy (PT), during treatment and after PT. The Pearson correlation coefficient was used to evaluate the correlation between the two methods. Results: Before PT, TCB and TSB showed a strong agreement (r = 0.9355). During PT, TCB readings slightly underestimated TSB (r = 0.9250). After PT, correlation also decreased (r = 0.9305). Bilirubin levels were significantly lower with TSB than TCB before, during and after PT (all P < 0.05). Bland-Altman plot analysis revealed good agreement between the two methods before initiating PT (mean difference of 0.0175 units), while the agreement was moderate during (mean difference of 0.1129 units) and after PT (mean difference of 1.2090 units). Conclusion: While TCB is a reliable non-invasive method for monitoring bilirubin levels, its accuracy is influenced by the timing of measurements and the phase of PT.