Within EONP, salivary PTX3, calprotectin, and IL-8 correlated with systemic indices and modestly enriched for blood-culture-positive bacteremia (combined model AUC 0.707).<h4>Conclusions</h4>Noninvasive salivary PTX3, calprotectin, and IL-8 are substantially elevated in early-onset neonatal pneumonia and mirror systemic inflammation. This evidence concerns the gene CXCL8 and bacterial infectious disease with sepsis.