Neonatal sepsis biomarkers: where are we now?

Given that neonatal sepsis remains an important factor contributing to mortality and morbidity in neonates, identification of accurate biomarkers to aid in its timely and accurate diagnosis is critical. In this review, we discuss the current evidence behind the use of biomarkers commonly used in clinical practice, as well as presenting recent developments in this area of research. Besides summarizing information regarding "traditional" biomarkers (eg, hematological indices, CRP, and other acute-phase reactants, cytokines), we provide the latest clinical status on some relatively "newer" biomarkers (eg, PCR- and "-omic" technology-based, biophysical biomarkers) in the diagnosis of neonatal sepsis. We believe that certain biophysical (RALIS, core-peripheral temperature differences) in combination with selective biochemical (procalcitonin, nCD64, presepsin) markers offer the best likelihood of being adopted for clinical use in the detection of neonatal sepsis in the near future. In addition, serial measurements of selective biochemical markers (procalcitonin, nCD64) offer promise in the decision to initiate and/or control the duration of antibiotic therapy. It is important to conduct adequately powered prospective multicenter studies to continue to establish the accuracy and safety of utilizing such biomarkers of neonatal sepsis so that appropriate and adequate therapy is tailored to each infant for optimal outcomes.