Significant changes in Complete Blood Count (CBC) and blood coagulation in SARS-CoV-2 infection: A retrospective study

Introduction: The aim of this work is to explore all the abnormalities of the hemogram and hemostasis tests in patients with severe COVID disease.
Methods: A cohort of patients with COVID-19 admitted to Avicenna military hospital in Marrakech during the 6 months from April to October 2020 was retrospectively analyzed. The baseline data of laboratory tests, including complete blood count (CBC) and coagulation tests.
Results: A total of 218 individuals were enrolled, with 82 patients meeting the criteria for severe covid and admitted to the intensive care unit, and 136 considered stable and admitted to the medicine departments.
The average age of patients with severe covid is significantly higher than non-severe patients (65.21 ± 5.71 versus 49.13 ± 7.81, p = 0.038).
Between the groups with severe and non-severe COVID-19: only platelets, lymphocytes and D-dimer showed statically significant difference (P= 0.0001, 0.003 and 0.0001 respectively). But the differences were relatively small for the other parameters.
The calculated parameters NLR, d-NLR, and LMR did not differ statistically between the two study groups with the exception of PLR, which was positively correlated with the severity of COVID (P= 0,007).
The ROC analysis showed that the best area under the curve (AUC) was obtained with platelet rate, D-dimer and PLR (0.86, 0.73 and 0.69 respectively) with the best cut-offs (250 g/L, 0.5mg/l and 300 correspondingly).
Conclusion: Thrombocytopenia, lymphopenia, increased PLR and D-dimers are often encountered during severe Covid and can be used as a predictive marker for the severity of the disease.