Serum Cytokine Levels As Critical Parameters in Early Diagnosis of Disease Progression in COVID-19: A Pilot Study


Background: The severity of Coronavirus disease 2019 (COVID-19) has been proposed to be associated with cytokine dysregulation. A significant number of patients become serious and need intensive care in hospitals.

Methods: The concentrations of cytokines interleukin (IL-6, IL-10) and tumor necrosis factor (TNF) were estimated using enzyme-linked immunosorbent assay (ELISA) in serum samples of 60 adult patients infected with SARS-CoV-2 along with 50 healthy controls of the same age. The mean age of the subjects was 50-52 years and included an equal number of males and females. The patients were further grouped as severe (38 patients) and non-severe cases (22 patients).

Results: The mean serum cytokine levels were significantly higher in the COVID-19 patients than in the healthy controls. IL-6 was excessively elevated in comparison to IL-10 and TNF. Comparative analysis of severe versus non-severe cases revealed only slight alterations in the cytokine levels: IL-6 being the most elevated in severe cases. The concentration of the liver enzyme ALT was higher than AST in both severe and non-severe cases. The mean concentration of serum electrolytes (Na, K, and Ca) did not vary much between the patients and healthy controls.

Conclusion: There was a significant positive correlation between the levels of cytokines serum biomarkers in COVID-19 patients. It may be suggested that early detection of cytokines, especially IL-6 and serum biomarkers can help predict disease prognosis and severity in COVID-19 patients.


COVID-19, Cytokines, disease severity, diagnosis, liver function, kidney function

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