ABSTRACT
OBJECTIVES: To assess the accuracy of transcutaneous bilirubin (TcB) measurements at 5 different body sites in Japanese very low birthweight (VLBW) infants and to determine a cut-off value of TcB to detect total serum/plasma bilirubin (TB) levels ≥10 mg/dL (171 µM). STUDY DESIGN: In a prospective multicenter study, 85 Japanese VLBW infants were enrolled from 5 neonatal intensive care units during the study period. A total of 383 blood samples from infants not receiving phototherapy or ≥24 hours postphototherapy were analyzed. TcB was measured at the forehead, sternum, upper back, lower abdomen, and waist within 1 hour of blood collection. Linear regression analysis and Bland-Altman plots were used to compare TcB values at each site with TB levels. The TcB cut-off value for detecting TB ≥10 mg/dL was determined by receiver operating characteristics curve analysis. RESULTS: TcB significantly correlated with TB, but the coefficient of determination varied among the sites (forehead: 0.5294, sternum: 0.6488, upper back: 0.6321, lower abdomen: 0.5430, waist: 0.7396). At a TcB value ≥8, the sensitivity was 100% at the sternum and upper back, 85% at the waist, 84% at the forehead, and 64% at the lower abdomen to detect TB ≥10 mg/dL. CONCLUSIONS: In Japanese VLBW infants, the accuracy of TcB measurements varies according to body site. TcB ≥8 on the sternum or upper back is more reliable than that on the forehead, lower abdomen, or waist to detect TB levels ≥10 mg/dL.