IL6 and COVID-19: Izcovich et al.’s systemic review identified the following potential risk factors for the severity and mortality in COVID-19 with high and moderate certainty of evidence: age, CKD, diabetes, obesity, neoplasia, creatinine level, LDH activity, procalcitonin concentration, D-dimer level, CRP concentration, etc.; related to IL-6 and ESR levels, there was no strong evidence of certainty (similar to our results) [30].