Serum ferritin-procalcitonin ratio as a predictor of outcomes in hospitalized patients with COVID-19 pneumonia

Abstract Background To identify the correlation between the ferritin-procalcitonin ratio and clinical outcomes including inhospital mortality and the requirement for mechanical ventilation in patients hospitalized with COVID-19. Methods This is a prospective observational cohort study, conducted on 60 patients diagnosed with COVID-19 admitted to the intensive care units of Kasr Al Ainy University Hospital. All patients had positive PCR results for COVID-19. All patients were assessed regarding the following inflammatory markers (CRP, ferritin, procalcitonin) and also the serum-ferritin procalcitonin ratio on days 1, 3, and 7 after hospital admission. Results There was no statistically significant difference between survivors and non-survivors regarding age, gender, and clinical presentations, but there was a statistically significant difference between the two groups regarding respiratory rate, oxygen saturation, initial FIO2 support ( P -value 0.028, < 0.001, < 0.001, respectively), and CRP and ferritin at day 3 ( P -value 0.007). Also, regarding platelets, lymphocytes and neutrophil/lymphocyte ratio ( P -value 0.034, 0.008, 0.002, respectively). As regards procalcitonin at day 3, there was a statistically significant difference between the two groups ( P -value 0.002). Although the median ferritin-procalcitonin ratio (FPR) levels were lower in non-survivors’ patients than survivors at day 1 and day 3, there was no statistical significance between the two groups at day 1 and day 3. By using ROC for the prediction of mortality using ferritin and PCT at day 1, in ferritin at day 1, the best cutoff value was 640 ng/mL with sensitivity = 73.7% and specificity = 60%, while, in procalcitonin at day 1, the best cutoff value was 0.181 ng/mL with sensitivity = 8 0% and specificity = 66.7%. Conclusions FPR, which is a simple analysis, can be used to predict disease severity and prognosis of COVID-19. It could be used as an alarming sign of high-risk mortality patients as FPR is inversely proportionate to COVID-19 severity. Procalcitonin is a good predictor for mechanical ventilation and mortality in COVID-19 patients. Ferritin is a poor predictor for mechanical ventilation and a good predictor for mortality in COVID-19 patients. D-dimer, IL-6, and neutrophil–lymphocyte ratio were good predictors, while CRP was a bad predictor for mortality in COVID-19 patients.