Hyperferritinemia has been associated with increased illness severity and adverse outcomes, including COVID-19. Elevated ferritin levels due to secondary haemophagocytic lympho- histiocytosis (sHLH) and cytokine storm syndrome have been reported in severe COVID-19 patients. In one of the studies, Ferritin is found to be elevated in non-survivors compared to survivors throughout the clinical course and increase with illness deterioration in COVID-19. This is proved to be an efficient biomarker used to help to track disease severity and mortality. It is used as first screening step for cytokine storm syndrome in COVID-19 patients with high fever.