ABSTRACT
SARS-CoV-2 is a systemic infection that has a significant impact on the hemostasis and hematopoietic system. Lymphopenia may be considered a cardinal laboratory finding, with prognostic potential. The study aimed to determine the differential leukocyte count in SARS-CoV-2 among Sudanese patients, during the period from March to December 2020. A total of 787 subjects were enrolled 487 patients with COVID-19 and 300 healthy volunteers as a control group;their ages ranged from 29 to 89 years. 3 ml of EDTA venous blood samples were collected from each participant standard for CBC investigation and then analyzed by SPSS version 21 (Mean and Standard deviation). A significant association between leukocyte count among ICU, ER group, and control with (P. value 0.000), in addition, a significant association was revealed among mild group and control group in differential neutrophil count, differential lymphocyte count, and absolute neutrophil count (p. value 0.000), however non-significant in TWBC absolute mixed cell count, absolute lymphocyte count, and differential mixed cells count (value 0.7,0.2, 0.19) respectively. The study concluded that leukocytosis with neutrophilia and lymphopenia is associated with the severity of SARS-CoV-2 infection, and should be implicated as predict for a serious course of the disease as well as mortality.