Leukocyte activation patterns in hospitalized children: comparing SARS-CoV-2, bacterial infections, and inflammatory pathologies

J Leukoc Biol. 2024 Oct 1;116(4):830-837. doi: 10.1093/jleuko/qiae093.

Abstract

In adults, monocytes and neutrophils play important roles in the hyperinflammatory responses characteristic of severe forms of SARS-CoV-2 infection. We assessed leukocyte activation in 55 children attending the emergency department for acute fever between March 2020 and September 2021. The following markers were analyzed by flow cytometry: CD169 and HLA-DR on monocytes, CD64 and CD16 on neutrophils, and CD38 on lymphocytes TCD8. Fifteen of the children had SARS-CoV-2 infection, 15 had bacterial infections, and 15 had inflammatory diseases. We observed overexpression of CD169 on monocytes and CD38 on T lymphocytes in all patients with a diagnosis of SARS-CoV-2, while overexpression of CD64 on neutrophils was observed with bacterial infections and inflammatory diseases. There was a decrease in the expression of HLA-DR on monocytes in the bacterial infection and inflammatory pathology groups. Leukocyte analysis identifies distinct activation patterns in children during SARS-CoV-2 infections, bacterial infections, and inflammatory diseases.

Keywords: SARS-CoV-2; biomarkers; child; leukocyte activation.

Publication types

  • Comparative Study

MeSH terms

  • ADP-ribosyl Cyclase 1 / metabolism
  • Adolescent
  • Bacterial Infections* / immunology
  • COVID-19* / immunology
  • COVID-19* / pathology
  • Child
  • Child, Hospitalized
  • Child, Preschool
  • Female
  • HLA-DR Antigens / immunology
  • HLA-DR Antigens / metabolism
  • Humans
  • Infant
  • Inflammation* / immunology
  • Leukocytes / immunology
  • Male
  • Monocytes / immunology
  • Neutrophils / immunology
  • Receptors, IgG / immunology
  • Receptors, IgG / metabolism
  • SARS-CoV-2* / immunology

Substances

  • HLA-DR Antigens
  • Receptors, IgG
  • ADP-ribosyl Cyclase 1

Grants and funding