Diagnostic and Prognostic Biomarkers of Coronavirus Disease 2019 in Children.

Predictors of early diagnosis and severe infection in children with coronavirus disease 2019 (COVID-19), which has killed more than 4 million people worldwide, have not been identified. However, some biomarkers, including cytokines and chemokines, are associated with the diagnosis, pathogenesis and severity of COVID-19 in adults. We examined whether such biomarkers can be used to predict the diagnosis and prognosis of COVID-19 in pediatric patients. Eighty-nine children were included in the study, comprising three patient groups of 69 patients (6 severe, 36 moderate and 27 mild) diagnosed with COVID-19 by real-time polymerase chain reaction observed for 2-216 months and clinical findings and 20 healthy children in the same age group. Hemogram, coagulation, inflammatory parameters and serum levels of 16 cytokines and chemokines were measured in blood samples and were analyzed and compared with clinical data. Interleukin 1-beta (IL-1β), interleukin-12 (IL-12) and interferon gamma-induced protein 10 (IP-10) levels were significantly higher in the COVID-19 patients (p = 0.035, p = 0.006 and p < 0.001). Additionally, D-dimer and IP-10 levels were higher in the severe group (p = 0.043 for D-dimer, area under the curve = 0.743, p = 0.027 for IP-10). Lymphocytes, C-reactive protein and procalcitonin levels were not diagnostic or prognostic factors in pediatric patients (p = 0.304, p = 0.144 and p = 0.67). Increased IL-1β, IL-12 and IP-10 levels in children with COVID-19 are indicators for early diagnosis, and D-dimer and IP-10 levels are predictive of disease severity. In children with COVID-19, these biomarkers can provide information on prognosis and enable early treatment.