Clinical Value of Hematological Inflammatory Indices in the Early Diagnosis of Neonatal Pneumonia.

Background: Neonatal pneumonia is a common and serious infectious disease in the neonatal period, particularly affecting preterm, low birth weight, and immunodeficient neonates, and poses a significant threat to their life and health. Finding convenient, reliable, and minimally invasive biomarkers is a key focus of clinical research. This study investigated the clinical value of the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic inflammatory index (SII) in the early diagnosis of neonatal pneumonia.

Methods: In this study, we retrospectively analyzed the clinical data of 322 patients with neonatal pneumonia diagnosed at our hospital from January through December 2023 and selected 80 healthy neonates from the same period as a control group. The severity of pneumonia was assessed using the Downes score, and general data and laboratory findings of the patients were collected and compared. Spearman's correlation analysis was used to explore the relationship between disease severity and each index, while multifactorial logistic regression analysis was employed to investigate the influencing factors. The value of NLR, PLR, and SII in the early diagnosis of neonatal pneumonia was evaluated using the receiver operating characteristic curve.

Results: Neutrophil count (NEU), platelet count (PLT), C-reactive protein (CRP), interleukin-6 (IL-6), NLR, PLR, and SII were significantly higher in the pneumonia group compared to the control group (p < 0.05). Correlation analysis showed that the Downes score positively correlated with NEU, PLT, NLR, PLR, SII, CRP, and IL-6 (p < 0.05). Multivariable logistic regression analysis indicated that PLR, CRP, and IL-6 were independent risk factors for the development of neonatal pneumonia (p < 0.05). The area under the curve (AUC) for diagnosing neonatal pneumonia was 0.770 for NLR, 0.805 for PLR, and 0.807 for SII.

Conclusions: PLR and SII have high diagnostic efficacy in the early diagnosis of neonatal pneumonia, while PLR, CRP, and IL-6 may be independent risk factors for neonatal pneumonia.