Predictive Role of NLR, dNLR, PLR, NLPR, and Other Laboratory Markers in Diagnosing SIRS in Premature Newborns

Abstract

Background: Premature newborns are at a significant risk for Systemic Inflammatory Response Syndrome SIRS, a condition associated with high morbidity and mortality. This study aimed to evaluate the predictive and diagnostic capability of laboratory markers like Neutrophil to Lymphocyte Ratio (NLR), derived Neutrophil to Lymphocyte Ratio (dNLR), Platelet-to-Lymphocyte Ratio (PLR), and Neutrophil-to-Lymphocyte-to-Platelet Ratio (NLPR) in diagnosing SIRS in premature newborns. Methods: Premature newborns with and without SIRS were evaluated in a prospective design during a one-year period. Among 136 newborns, early and 72 h post-birth analyses were performed. Results: At 24 h, NLR’s cutoff value was 8.69, yielding sensitivity and specificity rates of 52.77% and 83.47% (p = 0.0429), respectively. The dNLR showed a cutoff of 5.61, with corresponding rates of 63.27% and 84.15% (p = 0.0011), PLR had a cutoff of 408.75, with rates of 51.89% and 80.22% (p = 0.1026), and NLPR displayed a cutoff of 0.24, with rates of 75.85% and 86.70% (p = 0.0002). At 72 h, notable sensitivity and specificity improvements were observed, particularly with NLPR having a cutoff of 0.17, showing sensitivity of 77.74% and specificity of 95.18% (p < 0.0001). NLR above the cutoff indicated a 33% increase in SIRS risk, with a hazard ratio (HR)of 1.33. The dNLR was associated with a twofold increase in risk (HR 2.04). NLPR demonstrated a significant, over threefold increase in SIRS risk (HR 3.56), underscoring its strong predictive and diagnostic value for SIRS development. Conclusion: Integrating these findings into clinical practice could enhance neonatal care by facilitating the early identification and management of SIRS, potentially improving outcomes for this vulnerable population.