Analytical Methods Comparison for the Determination of Bilirubin in Blood Samples of Neonates

摘要

Analytical methods comparison for the determination of bilirubin in blood samples of neonates was compared to facilitate reliable clinical decision, detect hyperbilirubinemia (neonatal jaundice) or kernicterus in neonates. Details of analytical features such as accuracy, speed, sensitivity, specificity, the robustness of the methodologies/techniques compared are not well presented in some cases. In this prospective study carried out at Neonatal Special Care Unit (NSCU) of Nisa Premier Hospital Abuja, two methods: Total Serum Bilirubin (TSB) determination by direct spectrophotometry and Transcutaneous Bilirubinometry (TcB) by Jaundice Meter were compared using paired data of blood samples analysed respectively from 245 neonates<36 weeks. Data analysis was performed using Analyse-it? version 4.6 method validation software for Microsoft Excel. The overall mean value obtained by TcB (10.64±2.97mg/dl) was higher than the TSB (10.22±2.80 mg/dl), which was significantly different (ANOVA, p<.000). Bland-Altman analysis demonstrated a good agreement between TcB and TSB measurements (r = 0.976) but with an overestimation by TcB compared with evaluation with TSB (calculated by TcB-TSB), which was 2.95±17.84 mg/dl (95% CI = -0.85mg/dl to 1.70mg/dl). Relevant cut-off values were assessed and revealed that at 15mg/dl TcB provided 100% sensitivity (Area under the Curve - AUC = 99.6%) and 80% specificity. However at 13mg/dl TcB provided 98% sensitivity (AUC = 98.6%) and 66% specificity. It can be concluded that the use of TcB for bilirubin measurement in clinically jaundiced neonates is a rapid analytical methodology and the suitable alternative of TSB. However for safest clinical decisions bilirubin measurement by HPLC remains the gold standard methodology and is advocated.