Neonatal sepsis is a systemic infection in newborns, accompanied by a pronounced inflammatory response. Early clinical signs are often nonspecific, complicating timely diagnosis and leading to high mortality. IL-6 is a proinflammatory cytokine secreted by macrophages and other immune cells in response to infection. Its blood concentration rises earlier than classic inflammatory markers such as C-reactive protein (CRP), making IL-6 a promising tool for early diagnosis and assessment of sepsis severity in newborns.
aim of this study was to evaluate the diagnostic value of interleukin-6 in neonatal sepsis and to study its correlation with disease severity, based on clinical and laboratory parameters. Additionally, the goal was to determine IL-6 thresholds that differentiate mild, moderate, and severe sepsis in neonates.
Materials and Methods:
The study was conducted in a neonatal unit where 60 newborns aged up to 28 days were observed. Patients were divided into three groups: 1) confirmed sepsis (n=20), 2) suspected sepsis (n=20), 3) a control group of healthy newborns (n=20). All children underwent:
• clinical examination with assessment of signs of infection and severity of the condition;
• venous blood sampling to determine IL-6 levels using enzyme-linked immunosorbent assay (ELISA);
• parallel measurement of C-reactive protein and leukocytosis;
• statistical processing using correlation analysis between the level of IL-6 and the severity of clinical manifestations (APGAR scale, presence of septic shock, organ dysfunction).
IL-6 levels were significantly higher in neonates with confirmed sepsis compared to the control group ( p< 0.001). The mean IL-6 level was 150±35 pg /ml in patients with severe sepsis, 85±20 pg /ml in patients with moderate severity , and 42±15 pg /ml in patients with mild sepsis . Correlation analysis showed a strong association between IL-6 levels and disease severity (r=0.78; p< 0.001). An increase in IL-6 was observed earlier than an increase in CRP, confirming its value as an early marker.
The results confirm that IL-6 is a sensitive biomarker for the early detection of neonatal sepsis and correlates with the severity of clinical manifestations. Its use allows for the identification of patients with a high probability of severe disease and prompt initiation of intensive therapy. Combining IL-6 with other inflammatory markers and clinical parameters improves diagnostic accuracy and outcome prediction. A limitation of the study is the small sample size, requiring further multicenter studies to refine IL-6 thresholds.
Interleukin-6 is a valuable biomarker for neonatal sepsis, enabling early detection and assessment of disease severity. Incorporating IL-6 measurement into diagnostic protocols facilitates timely initiation of therapy, reduces the risk of complications, and improves the prognosis for newborns. To improve diagnostic accuracy, integrating IL-6 with other laboratory and clinical parameters is recommended.
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