The state of the cytokine system in patients with severe COVID-19

COVID-19 infection is one of the most actual problems of modern healthcare. Despite the progress made in understanding of the pathogenesis of this infection, there are currently no prognostic criteria for aggravation and death. A number of authors propose to consider interleukins 1, 6, 10 (IL-1, IL-6, IL-10) as markers of the prognosis of a severe course. We analyzed the clinical and laboratory characteristics of patients with severe COVID-19, including the interleukin 1, 6, 10 levels. We observed 49 patients with a severe form of COVID-19 aged 18 to 90 years, hospitalized in the intensive care unit of the Infectious Hospital. The diagnosis of Covid-19 was confirmed by the detection of SARS-CoV-2 RNA by PCR in nasopharyngeal and oropharyngeal smears. 47 patients had a burdened premorbid background. The most frequent complaints on admission were fever, shortness of breath, and dry cough. Bilateral polysegmental pneumonia was diagnosed at admission in all patients, but severe form (CT-3/4) was observed only in 32,7% of patients. Analysis of the studied cytokines (IL-1, IL-6, IL-10) in the blood serum of patients with severe Covid-19 revealed that IL-6 was elevated in more than 75% cases, while an increase in the level of IL-10 was noted in less than half of the patients (46,9%), and the IL-1 index above the baseline was recorded in less than a third of patients (12,2%).) We analyzed the clinical and laboratory characteristics of patients with severe COVID-19, depending on the outcome of the disease by the comparison groups: group 1 – survivors and group 2 – lethal. An increase of the concentration of IL-6 in group 1 was observed in 73,9% of the subjects, IL-1 – only in 4,3% of cases, and IL-10 – in 21,7% of patients. Elevated concentrations of IL-6 were detected in group 2 (with a fatal outcome) in 96,2% of patients, IL-10 in 69,2% of cases and IL-1 in 21,7% of patients. A simultaneous increase in the three cytokines studied was observed only in 12,2% of patients – all of them belonged to group 2. Thus, the cytokines studied can be considered as potential lethal markers for patients with severe COVID-19.

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