Evaluation of endothelial glycocalyx components levels in late-onset newborn sepsis

ABSTRACT Armağan Yalvaç S, Evaluation of Endothelial Glycocalyx Component Levels in Late-Onset Neonatal Sepsis, Eskişehir Osmangazi University Faculty of Medicine, Department of Pediatrics, Medical Specialization Thesis, Eskişehir, 2024. Neonatal infections continue to be a significant cause of morbidity and mortality in the first month of life. The diagnosis of neonatal sepsis is challenging due to the lack of specific signs and symptoms, the possibility of it being confused with non-infectious clinical conditions, and the absence of a perfect marker. On the surface of healthy endothelial cells, there is a dynamic glycocalyx layer that is in direct contact with blood and contains proteoglycans, glycoproteins, and glycosaminoglycan chains. The endothelial glycocalyx (EG) is one of the first targets of the inflammatory response during sepsis and is exposed to an early "cytokine storm." This study aims to investigate the relationship between the levels of EG components, Syndecan-1, Hyaluronan, and Heparan Sulfate, and septic shock and sepsis-associated disseminated intravascular coagulation (DIC) in neonates. The study included 39 neonates with an average gestational age of 32.77±4.25 weeks diagnosed with sepsis and 39 control group patients with an average gestational age of 32.62±3.94 weeks. In the study group, 14 patients developed septic shock. No significant difference was found in the levels of EG components between patients who developed septic shock and those who did not (p>0.05). When the relationship between the levels of EG components and sepsis-associated DIC was evaluated, it was found that the level of heparan sulfate was significantly correlated negatively with PLT (r=-0,439, p=0.005) and positively with d-dimer (r=0.536, p<0.001). The level of Syndecan-1 was found to be negatively correlated with PLT (r=-0.32, p=0.047). The ROC analysis performed to evaluate the diagnostic performance of the biomarkers showed that the AUC value for hyaluronan was 0.675, indicating a moderate level of diagnostic accuracy (p=0.008, 95% confidence interval 0.555-0.796). The ROC analysis results for Syndecan-1 and heparan sulfate did not show significant diagnostic capacity. These findings suggest that only the hyaluronan biomarker may be a potential indicator for the early diagnosis of sepsis in neonates. Key Words: Endothelial Glycocalyx, Heparan Sulfate, Hyaluranon, Newborn, Syndecan-1, Sepsis.