PROGNOSTIC VALUE OF BIOMARKERS FOR THE DURATION OF INPATIENT TREATMENT IN CHILDREN WITH COVID-19, ПРОГНОСТИЧНА ЦІННІСТЬ БІОМАРКЕРІВ ЩОДО ТРИВАЛОСТІ СТАЦІОНАРНОГО ЛІКУВАННЯ ДІТЕЙ ІЗ COVID-19

<jats:p>Introduction. COVID-19 in children usually has a mild or moderate course, but in some patients, it is associated with a prolonged clinical course and requires longer hospitalization. Identification of early prognostic biomarkers may improve clinical assessment and prognostic stratification of the disease. Aim. The aim of the study was to determine the prognostic significance of the biomarkers NSE, S100, IFABP, NGAL, and E-selectin for the duration of inpatient treatment in children with COVID-19 to facilitate individualized treatment strategies. Materials and methods. This retrospective comparative observational study included 88 children with laboratory-confirmed COVID-19 who were hospitalized in 2022-2023. Patients were divided into two groups according to the duration of hospitalization: ≤5 days (n=47) and &gt;5 days (n=41). Serum levels of NSE, S100, IFABP, NGAL, and E-selectin were determined by ELISA during hospitalization. Statistical analysis was performed using the licensed statistical software EZR (version 1.54), including the Mann–Whitney U test, Pearson’s χ² test, Spearman’s correlation analysis, and ROC analysis with determination of the area under the curve (AUC), sensitivity, and specificity. The statistical significance level was set at p&lt;0.05. Results. Children hospitalized for more than 5 days had higher levels of IFABP and NGAL than those with a shorter hospital stay (p&lt;0.05). According to the ROC analysis, the highest predictive value for prolonged hospitalization was demonstrated by IFABP (AUC=0.791) and NGAL (AUC=0.719), whereas E-selectin showed moderate predictive performance (AUC=0.663), and NSE and S100 showed limited predictive performance (AUC=0.591 and AUC=0.582, respectively). Correlation analysis confirmed statistically significant positive associations between the duration of hospitalization and the levels of IFABP (ρ=0.623; p=0.009), NGAL (ρ=0.611; p=0.01), and E-selectin (ρ=0.408; p=0.004). Conclusions. IFABP and NGAL are the most informative predictors of the duration of inpatient treatment in children with COVID-19. E-selectin has additional moderate prognostic value, whereas NSE and S100 have limited prognostic value. Elevated levels of IFABP, NGAL, and E-selectin are associated with longer hospitalization and may potentially serve as predictors of a prolonged disease course; however, these findings require further confirmation in prospective multicenter studies.</jats:p>