Neonatal sepsis remains a leading cause of morbidity and mortality in newborns, particularly due to the non-specificity of its early clinical signs. The limitations of conventional biomarkers like C-reactive protein and blood cultures have spurred the search for more rapid and reliable diagnostic tools. Procalcitonin and the analysis of cytokine profiles have emerged as promising biomarkers for the early identification of systemic infection. This review aims to evaluate the diagnostic significance of Procalcitonin and cytokine profiles, both individually and in combination, for the early detection of neonatal sepsis. A comprehensive literature review was conducted, analyzing recent studies and meta-analyses that investigate the use of Procalcitonin and various cytokines, including Interleukin-6, Interleukin-8, Interleukin-10, and Tumor Necrosis Factor-alpha, in diagnosing culture-proven and clinical neonatal sepsis. Their diagnostic accuracy, kinetics, and comparative performance were assessed. Procalcitonin demonstrates high sensitivity and specificity, with levels rising within two to four hours of infection and peaking at six to twelve hours, making it a valuable early marker. Among cytokines, Interleukin-6 shows the most promise as an early indicator due to its rapid elevation. However, the combination of a rapid-response marker like Interleukin-6 with a more stable and specific marker like Procalcitonin significantly improves diagnostic accuracy over any single biomarker. Multi-parameter models incorporating Procalcitonin, Interleukin-6, and clinical data show the highest predictive value.The integrated use of Procalcitonin and cytokine profiling, especially Interleukin-6, provides a superior approach for the early diagnosis of neonatal sepsis. This strategy enables timely intervention, reduces unnecessary antibiotic exposure, and has the potential to improve clinical outcomes. Future research should focus on standardizing assay cut-offs and validating point-of-care testing for widespread clinical implementation.

Neonatal Sepsis, Procalcitonin, Cytokines, Interleukin-6, Early Diagnosis, Biomarker, Diagnosis, Newborn, Infection.

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