A Comparison of Transcutaneous and Total Serum Bilirubin in Newborn Hispanic Infants at 35 or More Weeks of Gestation

Introduction: Transcutaneous bilirubin (TcB) measurement in newborns has been studied extensively in the non-Hispanic population, but its usefulness in the Hispanic population remains unclear. We evaluate the accuracy of TcB measurements in assessing jaundice in Hispanic neonates by using total serum bilirubin (TSB) measurements as the reference standard and determine the TcB level that can be used to identify neonates at risk for clinically significant jaundice (above the 95th percentile). Methods: A total of 192 Hispanic neonates were enrolled. TcB measurements were performed within 30 minutes of obtaining the TSB measurement. The linear relationship between TcB and TSB was measured by using the Pearson correlation coefficient (r). We calculated sensitivity, specificity, and positive and negative predictive values by using a TcB level above the 75th percentile to identify neonates with a TSB level above the 95th percentile. Results: TSB ranged from 1.7 to 13.9 mg/dL, with 62% falling below the 75th percentile. TcB correlated well with TSB in Hispanic neonates (r 0.87). A TcB level above the 75th percentile detected all infants with a TSB level above the 95th percentile, sensitivity 100%, and specificity 66%. Conclusions: In Hispanic newborns, the TcB level correlated well with the TSB level. TcB monitoring is a useful clinical screening tool to evaluate for the risk of clinically significant jaundice. (J Am Board Fam Med 2007;20:266‐271.)