Background and aims The American Academy of Paediatrics recommends the hour-specific evaluation of either skin (SB) or total serum bilirubin as screening tool for neonatal jaundice. However, serum bilirubin is not a good predictor of kernicterus, while SB represents a molecular specie already extravasated and passed into a tissue. Circulating unbound bilirubin (UB) is actually related to the neurotoxicity, being the portion of bilirubin capable to freely pass from circulation to the tissues. We aimed at exploring the relationship between SB and UB.
Methods Simultaneous measurements of SB (using 2nd generation transcutaneous devices) and UB were performed in 35 term jaundiced neonates.
Results In term neonates (mean GA: 38 weeks; BW 3095 g; postnatal age 74,8 h; TSB 250.8 µmol/L (SD 63); UB 0.48 (SD 0.2) µg/dL), a positive correlation was found between SB and UB (r = 0.70; p < 0.001; Figure 1). This correlation remained significant after adjustment for birth weight, gestational or postnatal age (partial correlation r = 0.68, p < 0.001; r = 0.69, p < 0.001; r = 0.64, p < 0.001).