INFLAMMATORY MARKERS IN NEONATAL SEPSIS

Abstract

Background: There is still an urgent medical need for the diagnosis of hyperinflammation associated with sepsis in the
newborn. In the case of neonatal sepsis, everything is complicated by many factors that affect the biomarker analysis: a
large variability in the degree of maturity at birth, features of the functioning of all organs and systems, and especially the
immune system.
Aim: Our research is devoted to the study of biomarkers of inflammation in early neonatal sepsis.
Materials and methods: Observational cohort study. In the study up to 75 newborns treated in intensive care units are
included. The criterion for defining a case of "sepsis" was a positive blood culture. The control group consisted of children
with negative blood culture, who were treated in the intensive care unit. We used bacteriological and immunological research
methods (flow cytometry for cell markers, immunofluorescence analysis of cytokines)
Statistical analysis was performed using the non-parametric Kruskal-Wallis test, Mann-Whitney test with Holm correction
(R statistics). Categorical data were calculated using the Chi-square test.
Results: C reactive protein showed a good applicability in the case of early neonatal sepsis, in contrast to procalcitonin,
which demonstrates an excellent specificity, has a low sensitivity and high variability.
Neither leukocytosis, leukopenia, leukocyte subpopulations showed reliable discriminatory characteristics. However, a
simple and publicly available neutrophil-lymphocyte index presented 80% specificity and generally proved to be a reliable
index. The basic immune status is characterized only by a decrease in CD8 lymphocytes. Cytokines are standard markers of
inflammation; however, it is difficult to obtain meaningful differences due to the abundance of cofactors that affect their
levels. But at the same time, sCD40 and IL-17a, which have not been sufficiently studied in neonatal sepsis, should be
recognized as extremely promising.
Conclusions: The study of inflammation markers of early neonatal sepsis showed that hyperinflammatory syndrome
prevails in the pathogenesis of neonatal sepsis. Significant variation in serum markers of newborns, including the classic
ones (CRP, PCT, NRL, interleukins 6, 8), suggests that they should be used with caution for diagnosis. There is a need to
study new new diagnostic targets based on markers of inflammation. According to the results of our study, sCD40 and IL17a, which were previously insufficiently studied in neonatal sepsis, should be recognized as such targets as extremely
promising markers.