The severity of netosis in patients with neonatal sepsis

Objective. To evaluate the severity of spontaneous netosis in peripheral blood in neonatal children with sepsis.

Characteristics of children and research methods. The researchers have studied the severity of spontaneous netosis in 12 neonates with sepsis who were hospitalized in the neonatal intensive care unit of the City Children’s Hospital No.1 in Kazan. The diagnose was based on a systemic inflammatory response syndrome, an increase in the concentration of C-reactive protein in the blood of more than 1 mg/dL, the presence of one or more foci of infection, the development of organ dysfunction, and the presence of a microorganism in venous blood.

Results. It was found that the initial period of neonatal sepsis proceeds against the background of activation of netosis, which was manifested by neutrophil extracellular traps in the peripheral blood. Their quantity and percentage was significantly higher compared to the indicators of the control group (p=0.02 and p=0.0007 accordingly). The highest levels of neutrophils in the state of netosis (67% and 70%) were found in 2 neonates with septic shock and leukopenia (2.7·10⁹/L and 2.8·10⁹/L, respectively). Only one neonate with septic shock developed absolute neutropenia (less than 2•10⁹/L) and leukopenia (less than 5·10⁹ / L). Thrombocytopenia was noted in 5 of 12 neonates with sepsis, which was less than 100•10⁹/L in every fourth child. At the same time, there were no clinical cases of hemorrhagic syndrome and blood clotting disorders.

Conclusion. The formation of neutrophilic extracellular traps is one of the most important mechanisms of anti-infective protection aimed at arresting the inflammatory process and clearing the internal media of the body.

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