INCREASED SERUM LEVELS OF INTERLEUKINS IL-6, IL-10, IL-17, AND IL-18 AS PREDICTORS OF ADVERSE OUTCOMES IN COVID-19-RELATED ACUTE RESPIRATORY DISTRESS SYNDROME

Abstract

Objective: The study evaluated the dynamics of interleukin (IL-6, IL-10, IL-17, and IL-18) levels in the serum of patients with acute respiratory distress syndrome (ARDS) during severe and critical COVID-19 to determine their prognostic significance. Methods: Seventy participants were examined: 50 patients with COVID-19 (mean age 45.5 years) and 20 healthy volunteers (mean age 42.5 years). Patients were divided into two subgroups: 1 – severe course (n=30, survivors) and 2 – critical course (n=20, non-survivors). Serum levels of IL-6, IL-10, IL-17, and IL-18 were measured on days 3, 5, 7, 10, and 16 using ELISA. The respiratory index (RI) and its correlation with interleukin levels were also assessed. Results: COVID-19 patients showed a statistically significant increase in IL-6, IL-10, and IL-17 levels, peaking on day 10: IL-6 (29.9±1.1 pg/mL in subgroup 2), IL-10 (26.3±1.3 pg/mL), and IL-17 (33.1±1.3 pg/mL); p<0.001 for all. Non-survivors showed a negative correlation between RI and interleukin levels. ROC analysis indicated that IL-6 levels >22.2 pg/mL on day 7 serve as an early prognostic marker of mortality. Conclusion: Early in the disease, elevated levels of IL-6, IL-10, and IL-17 are associated with ARDS and a high risk of mortality; furthermore, an IL-6 level >22.2 pg/mL on day 7 may serve as an early predictor of prognosis.