A score combining early detection of cytokines accurately predicts COVID-19 severity and intensive care unit transfer

Int J Infect Dis. 2020 Dec;101:342-345. doi: 10.1016/j.ijid.2020.10.003. Epub 2020 Oct 9.


Objectives: We aimed to explore cytokine profile in patients as it relates to Coronavirus Disease 2019 (COVID-19) severity, and to establish a predictive cytokine score to discriminate severe from non-severe cases and provide a prognosis parameter for patients that will require intensive care unit (ICU) transfer.

Methods: Serum samples of 63 patients diagnosed with SARS-CoV-2 infection were collected early after hospital admission (day 0-3). Patients were categorized in five groups based on the clinical presentation, the PaO2/FiO2 ratio and the requirement of mechanical ventilation.

Results: Three cytokines, IL-6, IL-8 and IL-10, were markedly higher in severe forms (n = 44) than in non-severe forms (n = 19) (p < 0.005). A score combining levels of these three cytokines (IL-6*IL-8*IL-10) had the highest performance to predict severity: sensitivity of 86.4% (95% CI, 72.4-94.8) and specificity of 94.7% (95% CI, 74.0-99.9) for a cutoff value of 2068 pg/mL. Elevated levels of IL-6, IL-8 and IL-10 were also found in critically ill patients. The combination of IL-6*IL-10 serum levels allowed the highest predictability for ICU transfer: AUC of 0.898 (p < 0.0001).

Conclusion: The combinatorial IL-6*IL-8*IL-10 score at presentation was highly predictive of the progression to a severe form of the disease, and could contribute to improve patient triage and to adapt therapeutic strategy within clinical trials more accurately and efficiently.

Keywords: COVID-19; Disease severity; IL-6; Inflammatory cytokines; Intensive care unit; Prediction.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • COVID-19 / blood*
  • COVID-19 / diagnosis
  • COVID-19 / therapy
  • COVID-19 / virology
  • Cytokines / blood*
  • Female
  • Hospitalization
  • Humans
  • Intensive Care Units / statistics & numerical data
  • Interleukins / blood
  • Male
  • Middle Aged
  • Pandemics
  • Prognosis
  • Respiration, Artificial
  • SARS-CoV-2 / genetics
  • SARS-CoV-2 / physiology
  • Severity of Illness Index
  • Young Adult


  • Cytokines
  • Interleukins