Research on Clinical Characteristics, Plasma Interleukin – 6 Concentrations, and Cytokine Storm Scores in COVID-19 Patients

Abstract

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus, originating in Wuhan, China in December 2019, and rapidly spreading worldwide. The main cause of the severe condition of COVID-19 is identified as the onset of a cytokine storm, with a key indicator being elevated levels of interleukin-6 (IL-6). Assessing the clinical severity as well as monitoring cytokine concentrations such as IL-6 and cytokine storm scores (CSs) play an important role in monitoring, treatment, and prognosis, helping to reduce the mortality rate of the disease. This study was conducted on 190 COVID-19 patients divided into two groups, including 169 severe patients and 21 mild patients. The results revealed that plasma IL-6 concentrations were higher in the severe group compared to the mild group at admission and after 5 - 7 days of treatment. An IL-6 threshold higher than 19.99 pg/ml had a prognostic value for severe clinical progression, with a sensitivity of 68.0% and specificity of 71.4%. There was no difference in cytokine storm scores between the severe and mild groups at admission. After 5 - 7 days of treatment, positive CSs were significantly higher in the severe group compared to the mild group, with CSs ≥ 2 being valuable in assessing disease severity, showing a sensitivity of 97.6% and specificity of 50.0%. Elevated plasma IL-6 levels were significantly correlated with positive CSs in severe COVID-19 patients.