tetano
Editor, Senior Moderator
Ann Lab Med
. 2025 Oct 13.
doi: 10.3343/alm.2025.0209. Online ahead of print. Peripheral White Blood Cell Dynamics as a Biomarker of Coronavirus Disease Severity
Joung Ha Park[SUP] 1 [/SUP], Hyemin Chung[SUP] 1 [/SUP], Min-Chul Kim[SUP] 1 [/SUP], Seong-Ho Choi[SUP] 2 [/SUP], Jin-Won Chung[SUP] 2 [/SUP], Hye Ryoun Kim[SUP] 3 [/SUP]
Affiliations
Background: Despite widespread vaccination efforts against severe acute respiratory syndrome coronavirus 2, variants with increased transmissibility or immune evasion continue to emerge, posing a considerable challenge. Understanding the immunological factors associated with coronavirus disease (COVID-19) progression is essential for improving patient management and treatment strategies. We explored the dynamic changes in the peripheral white blood cell (WBC) profile, including T lymphocyte subsets, to assess their potential as predictors of disease severity and progression.
Methods: Two hundred fifty-eight patients hospitalized for confirmed COVID-19 were classified into four sub-cohorts based on changes in disease severity over 7 days. WBC parameters, including absolute neutrophil, total lymphocyte, and T cell subset counts, and the neutrophil-to-lymphocyte ratio (NLR) were assessed at admission and after 7 days.
Results: Patients with persistent mild-to-moderate illness exhibited a marked increase in the lymphocyte count and a decrease in the NLR over time. In contrast, patients with sustained severe-to-critical illness showed an increasing WBC count without a corresponding increase in the lymphocyte count, in addition to a marked elevation in the NLR. Patients whose condition improved from severe-to-critical to mild-to-moderate illness showed increased cluster of differentiation (CD)3[SUP]+[/SUP] and CD4[SUP]+[/SUP] T cell counts and an elevated CD4/CD8 ratio, whereas the NLR did not significantly change.
Conclusions: The early-phase dynamics of T cell subsets may serve as a useful biomarker of disease severity and recovery in patients with COVID-19. Monitoring these immunological changes may help support clinical decision-making and inform the timing of therapeutic interventions.
Keywords: Biomarkers; COVID-19; Immunological factors; Leukocyte count; T lymphocyte subsets.
. 2025 Oct 13.
doi: 10.3343/alm.2025.0209. Online ahead of print. Peripheral White Blood Cell Dynamics as a Biomarker of Coronavirus Disease Severity
Joung Ha Park[SUP] 1 [/SUP], Hyemin Chung[SUP] 1 [/SUP], Min-Chul Kim[SUP] 1 [/SUP], Seong-Ho Choi[SUP] 2 [/SUP], Jin-Won Chung[SUP] 2 [/SUP], Hye Ryoun Kim[SUP] 3 [/SUP]
Affiliations
- PMID: 41077959
- DOI: 10.3343/alm.2025.0209
Background: Despite widespread vaccination efforts against severe acute respiratory syndrome coronavirus 2, variants with increased transmissibility or immune evasion continue to emerge, posing a considerable challenge. Understanding the immunological factors associated with coronavirus disease (COVID-19) progression is essential for improving patient management and treatment strategies. We explored the dynamic changes in the peripheral white blood cell (WBC) profile, including T lymphocyte subsets, to assess their potential as predictors of disease severity and progression.
Methods: Two hundred fifty-eight patients hospitalized for confirmed COVID-19 were classified into four sub-cohorts based on changes in disease severity over 7 days. WBC parameters, including absolute neutrophil, total lymphocyte, and T cell subset counts, and the neutrophil-to-lymphocyte ratio (NLR) were assessed at admission and after 7 days.
Results: Patients with persistent mild-to-moderate illness exhibited a marked increase in the lymphocyte count and a decrease in the NLR over time. In contrast, patients with sustained severe-to-critical illness showed an increasing WBC count without a corresponding increase in the lymphocyte count, in addition to a marked elevation in the NLR. Patients whose condition improved from severe-to-critical to mild-to-moderate illness showed increased cluster of differentiation (CD)3[SUP]+[/SUP] and CD4[SUP]+[/SUP] T cell counts and an elevated CD4/CD8 ratio, whereas the NLR did not significantly change.
Conclusions: The early-phase dynamics of T cell subsets may serve as a useful biomarker of disease severity and recovery in patients with COVID-19. Monitoring these immunological changes may help support clinical decision-making and inform the timing of therapeutic interventions.
Keywords: Biomarkers; COVID-19; Immunological factors; Leukocyte count; T lymphocyte subsets.