Immune Cell Composition and Its Impact on Prognosis in Children with Sepsis

Given the critical role of immune cells and their responses in sepsis pathogenesis, this study aimed to evaluate the prognostic significance of various immune cell ratios in septic children through the collection and analysis of clinical data. Clinical data were collected from septic children admitted to the pediatric intensive care unit (PICU) of Shenzhen Children’s Hospital between January 2019 and September 2021. The peripheral blood immune cell ratios included the neutrophil to lymphocyte ratio (NLR), the derived neutrophil to lymphocyte ratio (dNLR), the neutrophil to lymphocyte and platelet ratio (NLPR), the monocyte to lymphocyte ratio (MLR), and the platelet to lymphocyte ratio (PLR). To investigate the associations between these immune cell ratios and mortality, we utilized the locally weighted scatterplot smoothing (LOWESS) method, receiver operating characteristic (ROC) analysis, and Kaplan‒Meier (K‒M) analysis. A total of 230 septic children were enrolled in the study. When comparing the immune cell ratios between the deceased and surviving groups, all ratios except for the PLR were elevated in the deceased group. Using the LOWESS method, we observed that the MLR, NLR, dNLR, and NLPR exhibited an approximately linear association with in-hospital mortality. Among the various immune cell ratios, the NLPR exhibited the highest AUC of 0.748, which was statistically comparable to that of the Pediatric Critical Illness Score (PCIS) (0.748 vs. 0.738, P = 0.852). The NLR (0.652), MLR (0.638), and dNLR (0.615) followed in terms of AUC values. K‒M analysis revealed that children with elevated MLR, NLR, dNLR, and NLPR exhibited increased 30-day mortality. The predictive capacity of the NLPR is comparable to that of the PCIS, suggesting that the NLPR has potential as a robust prognostic indicator for septic children.