The strong pro-inflammatory response known as cytokine storm is said to play an important role in the pathophysiology of a severe variant of covid-19. But researchers at Radboudumc University (Matthijs Kox et al.) doubt that.
In a small-scale study published in JAMA, they argue that many studies look at different cytokines and do not make a comparison with other syndromes. That is why they took a different approach. Kox et al measured the concentrations of tumor necrosis factor alpha (TNF-α) and the interleukins 6 and 8 (IL-6, IL-8) in different patients in the ic: patients with covid-19 who met the criteria of the acute respiratory distress syndrome (ARDS), patients with bacterial septic shock (with and without ARDS) and in patients who ended up in the ICU after cardiac arrest or serious trauma.
The concentrations of all these cytokines were found to be significantly less elevated in covid-19 patients than in patients with septic shock and ARDS. And compared to septic shock patients without ARDS, covid-19 patients had lower IL-6 and IL-8 levels.
While TNF levels in patients with covid-19 were higher than in trauma patients, the researchers found no differences between patients with covid-19 and patients with cardiac arrest or trauma for IL-6 and even lower levels for IL-8. in patients with covid-19 compared to patients with cardiac arrest and no differences from the trauma patients.
All in all, sufficient reason for Kox et al. To doubt whether the increased concentrations of cytokines could explain the severe variant of covid-19 seen on the IC.