Study of the Variability of Transcutaneous Bilirubin Determinations Between Different Ethnic Groups.

Background: Pathological hyperbilirubinemia often leads to hospital readmission within the first week of life, with increased risk of neurological damage if untreated. Transcutaneous bilirubin (TcB) measurement was integrated into neonatal screening to estimate total serum bilirubin (SB) concentrations. Despite TcB and SB generally correlating well, discrepancies can occur based on race/ethnicity. Falsely elevated TcB readings may be obtained in darker skin pigmentation.

Aims: This study compared TcB and SB across different ethnic groups to assess correlation patterns and identify the best TcB measurement method in neonates.

Methods: Term and late preterm neonates delivered at the University Hospital of Vic were included. Each newborn underwent TcB assessment (in the forehead, sternum, and both sites simultaneously) concomitantly with SB measurement. The correlations between both parameters were analyzed.

Results: A total of 148 neonates were categorized as White/Caucasian (58), Chinese (3), Indian (17), Black/African (22), Latino (11), Arab (25), or mixed (12). The groups were homogeneous, with statistical differences in delivery and feeding ( = 0.032 and < 0.001). Differences between TcB and SB were -0.19 for White/Caucasian, 0.90 for Chinese, 1.12 for Indian, 2.47 for Black/African, 0.42 for Latino, and -0.08 for Arab ( < 0.001). A high association between TcB and SB was obtained with all measurement methods: r = 0.836 in forehead, r = 0.869 in midsternum, and r = 0.863 when both locations were combined ( < 0.001).

Conclusions: TcB correlated well with SB, but accuracy varied among ethnic groups. An individualized interpretation of TcB based on skin pigmentation is supported. Mid-sternum determination was the best TcB measurement method.