Blood IL-6 levels as a Predictor of the Clinical Course Severity in COVID-19 Infection: data from the Republic of Armenia

Patients with severe cases of COVID-19 infection can develop acute respiratory distress syndrome, septic shock, multiple system organ failure, bleeding, and coagulation dysfunction. Severe forms of COVID-19 are characterized by viral pneumonia patterns and are frequently associated with elevated serum levels of pro-inflammatory cytokines forming a “cytokine storm”. Among the mediators of cytokines release syndrome, interleukin-6 is one of the key cytokines. Tocilizumab, a monoclonal antibody against interleukin-6 receptor, may provide clinical benefit for selected COVID-19 patients with high inflammatory biomarkers. In this prospective study, we aimed to correlate the blood levels of interleukin 6, C-reactive protein, procalcitonin and other biomarkers to the clinical course and outcome of COVID-19 patients in our study cohort.
Our study shows that several biomarkers and in particular serum interleukin-6 levels differ according to disease severity in COVID-19 infection. Serum interleukin-6 levels were also significantly increased in non-survivors and could raise the potential benefit of tocilizumab for selected cases of COVID-19 infection. Data about the efficacy of tocilizumab are conflicting. However, our data about tocilizumab may suggest a potential benefit, and is in-line with previous data about the absence of significant risk of super-infection. The early short-term administration of methylprednisolone in a 250-500mg/daily dosage revealed good results with and without concurrent tocilizumab therapy.