Correlates of the SARS-CoV-2 Ag or Total Ig antibody levels with hematological parameters in Greek hospitalized COVID-19 patients

Abstract

Introduction: COVID-19 patients present with hematological changes. Data regarding the relation between SARS-CoV-2 Ag or Total Ig antibody levels and hematological profile in Greek COVID-19 patients are limited.

Aims: To identify probable correlates between SARS-CoV-2 antibody titers and hematological parameters in a cohort of hospitalized patients in the COVID-19 Unit of the University of Thessaly in Greece from November to December 2020.

Methods: Nasopharyngeal swabs and whole blood specimens were obtained every two days from admission to discharge or death. The SARS-CoV-2 nucleocapsid protein and the IgA, IgM, IgG spike protein-specific antibodies were quantitatively determined in each patient by lateral flow assays (Prognosis Biotech, Larissa, Greece). Hematological parameters were recorded at the same time points.

Results: 40 Greek COVID-19 patients (31 male, 9 female) with a median age of 59.50±16.21 years were enrolled in the study. The median time from symptom onset to hospitalization was 8.0±4.19 days. All patients had pneumonia on chest computed tomography. A significant negative correlation was found between the SARS-CoV-2 Ag and Total Ig levels (ρ=-0.489/p<0.001). SARS-CoV-2 Ag levels were inversely correlated with white blood cell (WBC) (ρ=-0.227/p=0.002), platelet (ρ=-0.327/p<0.001) and lymphocyte counts (ρ=-0.216/p=0.004). Total Ig levels were positively correlated with WBC, neutrophils, platelets and lymphocytes (ρ=0.257/p=0.001; ρ=0.259/p=<0.001; r=0.262/p=<0.001 and r=0.161/p=0.031, respectively).

Conclusions: Our results indicate an association between SARS-CoV-2 Ag or Total Ig antibody responses with altered blood parameters.