Introduction: During the COVID19 pandemic researchers struggled to find biomarkers that
could reliably distinguish COVID19 from bacterial pneumonia. Some of them relied on
determining the relationship between ferritin and procalcitonin (PCT) called (F/P) ratio. Aim:
The purpose of this research was to find out if the F/P could be reliable biomarker in the rapid
distinguish COVID19 from bacterial pneumonia due to arrival of other results. Methods: This
research included 81 patients with pneumonia, 58 caused by COVID19 and 23 caused by
bacterial infection. Patients under the age of 18, with sepsis comfirmed by positive blood culture,
pregnant women, death on admission, missing baseline data, cancer patients and all patients with
bacterial/fungal co-infection during COVID19 were excluded from this research. Control group
were patients with bacterial pneumonia and negative results of rapid antigen test and/ or
polymerase chain reaction (PCR) test. Results: We found the F/P level was
significantly higher in COVID-19 compared with bacterial pneumonia patients ((F/P?877
(86.21% vs 65.21%; p=0.038) and F/P?2348.57 (60.34% vs 26.09%; p=0.005)). Conclusion:
F/P ratio could be used as one of the biomarkers for distinguish COVID from bacterial
pneumonia.

Keyword: ferritin, procalcitonin, COVID19, bacterial, pneumonia