Procalcitonin, Presepsin, Endocan, and Interleukin-6 in the Early Diagnosis of Neonatal Sepsis—A Prospective Study

<b>Background/Objectives</b>: Neonatal early-onset sepsis (EOS) is a life-threatening condition, and numerous efforts have been invested in identifying the most promising biomarkers for its detection. In this prospective cohort study, we aimed to determine the diagnostic accuracy and optimal cut-off values of procalcitonin (PCT), presepsin, endocan, and interleukin (IL)-6 determined from the neonatal serum (0-12, 24-48, and 72-96 h), and umbilical blood cord for the diagnosis of EOS. <b>Methods</b>: A total of 122 patients were included in this study and were divided into two groups: group 1 (sepsis, n = 68 patients) and group 2 (without sepsis, n = 54 patients). Maternal and neonatal characteristics were assessed using descriptive statistics. Logistic regressions were used to evaluate the association between various biomarkers and the presence of EOS and to adjust for potential confounders. Using sensitivity analysis and Youden's index from the ROC curve, the biomarkers' diagnostic accuracy and optimal cut-off values were obtained. <b>Results</b>: PCT at 0-12 and 24-48 h of life exhibited the best diagnostic performance, with sensitivities (Ses) of 75% and 76.5% and specificities (Sps) above 74%. Presepsin demonstrated excellent performance at 24-48 h, with Ses of 68.42%, and Sps of 88.89%. IL-6 and endocan achieved modest results for the detection of EOS. <b>Conclusions</b>: PCT and presepsin measured at early neonatal timepoints demonstrated high diagnostic accuracy and favorable sensitivity-specificity balance for predicting EOS.