The Value of Neutrophil to Lymphocyte Ratio and Platelet to Lymphocyte Ratio for Detecting Early-onset Neonatal Sepsis.

Objective: The purpose of this study was to investigate the relationship between neonate early-onset sepsis (EOS) and the neutrophil to lymphocyte ratio (NLR) and the platelet to lymphocyte ratio (PLR) of term neonates.

Materials And Methods: This prospective observational study was conducted with term neonates diagnosed with EOS compared with 44 healthy controls. Exclusion criteria were prematurity, postmaturity, small or large for gestational age according to week of pregnancy, preeclampsia, gestational diabetes mellitus, chorioamnionitis, congenital major anomalies, and cyanotic congenital heart disease.

Results: A total of 122 term neonates were included in the study. Of these, 78 were diagnosed with EOS and 44 were healthy controls. Tachycardia and apnea with bradycardia were the most common clinical signs of the onset of EOS in neonates in the EOS group. This group had significantly higher neutrophil counts, axillary temperatures, NLRs, PLRs, C-reactive proteins, and procalcitonin levels compared with the control group. There was a positive association between neutrophil counts, NLR, and PLR in the EOS group. An NLR of 6.76 was determined as the predictive cutoff value of neonate EOS (sensitivity 97.4%; specificity 100%; area under the receiver-operating characteristic curve 0.99; P=0.001). A PLR of 94.05 was determined as the predictive cutoff value of neonate EOS (sensitivity 97.4; specificity 100%; area under the receiver-operating characteristic curve 0.93; P=0.001).

Conclusions: NLRs and PLRs were positively correlated with EOS in term neonates, and these ratios can be used as diagnostic adjunct tests for neonate EOS workups.