The usefulness of ferritin as a biomarker in evaluating the severity of disease in wave one and wave two of COVID-19 patients – A comparative retrospective study

Background: Serum ferritin was found to be a positive acute phase protein and it was linked to a hyperinflammatory process, cytokine storm, and multiple organ damage in coronavirus disease (COVID-19). Objective: The objective of this study was to establish whether ferritin could be utilized as a biomarker to evaluate disease severity in COVID-19 waves one and two in hospitalized patients. Materials and Methods: It was an observational, retrospective study. A total of 2093 patients' data with confirmed reverse transcriptase-polymerase chain reaction positive for COVID-19 disease were reviewed. Serum ferritin values on the day of hospital admission were compared in both waves among different grades of clinical severity correlated in terms of survival and death. Results: Survivors in wave one were 92.5% and 85.4% in wave two. In waves one and two, the nonsurvivor rate was 7.5% and 14.6%, respectively, with statistically significant P values of 0.001. Analysis of the receiver operating curve (ROC) showed the ideal ferritin cutoff point for death is 687.6 ng/mL (sensitivity: 70%; specificity: 57.3%), with an Area under curve (AUC) of 0.67, suggesting that ferritin was a better marker of mortality and severity in the first wave. In the second wave, the cutoff for severity is 583.9 ng/mL (sensitivity of 85.1%, specificity of 54.8%). AUC 0.74 suggested a marker of severity in the second wave. Conclusion: Elevated serum ferritin levels in the first wave indicated severity and mortality with exaggerated cytokine storm and early organ damage and severity in the second wave, indicating reduced inflammation and better treatment plan.