Systematic Evaluation of Hematologic Parameters and Blood Smear Findings in Patients With SARS-CoV-2 vs Other Viral Respiratory Infections

Abstract

Objectives: We evaluated and compared the peripheral blood findings in patients with acute COVID-19 vs other viral respiratory infections. Methods: We retrospectively reviewed peripheral blood counts and smear morphology in patients with a positive viral respiratory panel (VRP) or SARS-CoV-2 test. Results: A total of 97 peripheral blood samples (COVID-19 infection, 53; VRP positive, 44) from 50 patients (mean [SD] age, 45.8 [20.8] years; females 52%) were reviewed. There were no statistically significant differences in the demographic characteristics between the 2 groups. The most common peripheral blood abnormalities were anemia, thrombocytopenia, absolute lymphopenia, and reactive lymphocytes. The following peripheral blood findings were significantly associated with other viral respiratory infections compared with COVID-19 infection: low red blood cell count, low hematocrit, high mean corpuscular volume, thrombocytopenia, low mean platelet volume, high red cell distribution width, band neutrophilia, and toxic granulation in neutrophils. Conclusions: Our study showed that there are several peripheral blood count and morphologic abnormalities seen in patients with COVID-19, but most of these findings lack specificity as they are also seen in the other viral respiratory infections.