CRP and COVID-19: Low fT3 values were also correlated with increased levels of inflammation (high-sensitivity CRP), tissue damage (LDH, ferritin, high-sensitivity cardiac troponin I) and coagulation (prothrombin time, fibrinogen, D-dimer) serum markers, as well as with higher radiological scores of disease severity (Lung Immune Prognostic Index, Sequential Organ Failure Assessment Score and Tomographic severity score), clearly indicating that reduced fT3 levels can be considered as a prognostic biomarker of COVID-19 [92].