Association between serum inflammatory parameters and the disease severity in COVID-19 patients

J Clin Lab Anal. 2022 Jan;36(1):e24162. doi: 10.1002/jcla.24162. Epub 2021 Dec 7.

Abstract

Objective: Most patients infected with the novel coronavirus (SARS-CoV-2), as the causative agent of COVID-19 disease, show mild symptoms, but some of them develop severe illness. The purpose of this study was to analyze the blood markers of COVID-19 patients and to investigate the correlation between serum inflammatory cytokines and the disease severity.

Methods: In this prospective cross-sectional study, 50 patients with COVID-19 and 20 patients without COVID-19 were enrolled. According to ICU admission criteria, patients were divided into two groups of non-severe and severe. Differences in the serum levels of C-reactive protein (CRP), IL-6, and TNF-α, as well as erythrocyte sedimentation rate (ESR), lymphocytes (LYM) count, and neutrophils (NEU) count between the two groups were determined and analyzed.

Results: Out of the 50 patients with COVID-19, 14 were diagnosed as severe cases. There was no significant difference between the two groups of COVID-19 patients in terms of gender and age. Blood tests of COVID-19 patients showed a significant decrease and increase in NEU and LYM counts, respectively. There were significant differences in the serum levels of IL-6, TNF-α, and CRP between the severe and non-severe groups, which were higher in the severe group. Also, there was a significant correlation between the disease severity and CRP with ESR (r = 0.79), CRP with IL-6 (r = 0.74), LYM with NEU (r = -0.97), and ESR with TNF-α (r = 0.7).

Conclusion: The findings of this study, as the first study in Iran, suggest that the levels of IL-6, TNF-α, ESR, and CRP could be used to predict the severity of COVID-19 disease.

Keywords: COVID-19; CRP; IL-6; SARS-CoV-2; TNF-α; cytokines.

MeSH terms

  • Adult
  • Aged
  • Biomarkers / blood*
  • Blood Sedimentation
  • C-Reactive Protein / analysis
  • COVID-19 / blood
  • COVID-19 / etiology*
  • Case-Control Studies
  • Cross-Sectional Studies
  • Female
  • Humans
  • Inflammation / blood*
  • Inflammation / virology
  • Interleukin-6 / blood
  • Lymphocyte Count
  • Male
  • Middle Aged
  • Prospective Studies
  • Severity of Illness Index
  • Tumor Necrosis Factor-alpha / blood
  • Young Adult

Substances

  • Biomarkers
  • IL6 protein, human
  • Interleukin-6
  • Tumor Necrosis Factor-alpha
  • C-Reactive Protein