Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 17 2 2023 04 17 89 99 Farhad Shahi Breast Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran Reza Safaee Department of Medical Oncology, Tehran University of Medical Sciences, Tehran, Iran Saba Fekrvand Tehran University of Medical Sciences, School of Medicine, Tehran, Iran Fatemeh Fathi Tehran University of Medical Sciences, School of Medicine, Tehran, Iran Mohammad Reza Dabiri Department of Medical Oncology, Tehran University of Medical Sciences, Tehran, Iran Alireza Abdollahi Department of Pathology, School of Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran Hanieh Hosseini Department of Internal Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran 2022 07 26 2023 03 15 Background: Since 2019, Coronavirus has been a highly contagious disease. The COVID-19 outbreak was declared a pandemic by the World Health Organization in March 2020. Variable laboratory findings are reported in COVID-19 patients, among which elevated levels of D-dimer, lactate dehydrogenase, as well as lymphopenia, have been reported to be associated with increased severity of disease symptoms requiring ventilator support, intensive care unit admission, and mortality. Materials and Methods: In the current study, inclusion criteria were: patient age above 18 years and hospitalization in the Imam Khomeini hospital with COVID-19 disease confirmed with nasopharyngeal swab polymerase chain reaction tests. Levels of white blood cells, neutrophils, lymphocytes, hemoglobin, platelets, D-dimer, C-reactive protein, LDH, and ferritin were measured and their correlation with the final patients’ outcome was evaluated. Results: A total of 208 patients were included in the present study. Higher neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte, LDH, platelet to lymphocyte ratio, ferritin, and D-dimer were significantly related to O2 dependency. Neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte and LDH were significantly related to higher rates of mortality. Higher Hb and lymphocyte count were significantly related to higher rates of survival. Conclusion: Hematological parameters including neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte, LDH, platelet to lymphocyte ratio, ferritin, D-dimer, Hb, and lymphocyte count were significantly related to the prognosis of patients with COVID-19 disease. This could help decide which COVID-19 patients have priority for hospitalization and intensive medical care, particularly when the pandemic disease causes limitations in healthcare service. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/1883 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/1883/968