IL6 and COVID-19: Recently, among blood biomarkers measured from 187 patients admitted at hospital with diagnosis of COVID-19, also including IL-6, Krebs von den Lungen 6, troponin, ferritin, lactate dehydrogenase, B-type natriuretic peptide, PCT, and CRP, the strongest association with negative outcomes, defined as noninvasive ventilation or ICU admission, was the high levels of soluble urokinase plasminogen activator receptor (suPAR) and IL-6 [28].