CONCENTRAÇÕES ELEVADAS DAS CITOCINAS ASSOCIADAS À RESPOSTA Th17 E DESFECHOS DESFAVORÁVEIS EM PACIENTES COM COVID-19 ADMITIDOS À UNIDADE DE TERAPIA INTENSIVA

Abstract

COVID-19 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is now understood that the immune response plays a crucial role in modulating the severity and outcome of this disease. In this context, the Th17 response has been receiving increasing attention due to its ability to modulate inflammation. A prospective inclusion of 56 COVID-19 patients admitted to the Intensive Care Unit (ICU) of the General Hospital of Vitória da Conquista (HGVC) in Bahia, Brazil, was conducted. All included patients had SARS-CoV-2 infection confirmed through real-time polymerase chain reaction (RT-PCR) of nasopharyngeal swab samples. Serum samples were collected from all participants to determine the concentration of Th17-associated cytokines (IL-1β, TGF-β, IL-6, IL-17, and IL-23) using enzyme-linked immunosorbent assay (ELISA). The Shapiro-Wilk test assessed the normality of data distribution, and Levene's test verified variance homogeneity. Student's t-test was employed for mean comparisons, and chi-square independence tests (2x2) examined associations between categorical variables. Lastly, Spearman correlation evaluated associations between cytokines and the mortality outcome variable. It was initially demonstrated that male patients had a higher likelihood of mortality compared to female patients. Deceased patients exhibited higher levels of IL-1β and IL-6 compared to those discharged, while TGF-β levels in deceased patients were substantially elevated. Although statistically significant differences were not observed, there was a trend of higher levels of IL-17 and IL-23 in patients who succumbed to mortality. IL-1β and TGF-β showed a significant strong correlation with the mortality outcome, while IL-6 presented a moderate correlation. Strong significant correlations were found between IL-1β and TGF-β, as well as between IL-6 and IL-17, and IL-6 and IL-23, with a moderate correlation observed between IL-6 and TGF-β. Finally, IL-17 and IL-23 exhibited a significant correlation with each other. Based on our analysis, we conclude that elevated levels of cytokines IL-1β, TGF-β, and IL-6 are significantly associated with an unfavorable outcome in SARS-CoV-2 patients, irrespective of comorbidities. These cytokines may play a crucial role in the pathogenesis of the disease and serve as useful indicators for assessing the severity and prognosis of SARS-CoV-2-infected patients.