Serum IL-6: A potential biomarker of mortality among SARS-CoV-2 infected patients in Mexico.

BACKGROUND: The first case of SARS-CoV-2 in Mexico was reported in February 2020, since then, high rates of mortality due to COVID-19 have been found. Cytokine storm is linked to the severity and decreasing the survival among infected patients by COVID-19. The serum levels of Interleukin 6 (IL-6) have been correlated to mortality in COVID-19 cases and could be used as indicator of mortality in COVID-19 cases. The aim of this study was to determine levels of IL-6 and assess its usefulness as indicator of mortality among COVID-19 patients from Mexico. METHODS: A cohort study among 38 adults (28 men, 10 women) was carried out in the Regional High Specialty Hospital of the Yucatan Peninsula in Merida, Yucatan, Mexico. Demographic and clinical biochemistry data were collected. The serum levels of IL-6 were measured in each patient by specific immunoassays. RESULTS: High frequency of mortality (36.84%) was found in the sample. The average age of individuals that non-survive was significantly higher (59.71 ± 13.83 years) than the survival group (43.29 ± 11.80 years). Serum levels of IL-6 were significantly higher in patients that did not survive. A correlation between IL-6 levels with lymphocyte count, LDH, CRP and procaciltonin was found. The optimal cutoff value of IL-6 was 30.95 pg/mL with high sensitivity and specificity. CONCLUSION: Our findings demonstrate that level of IL-6 is an indicator of mortality among hospitalized COVID-19 patients in Mexico.

IL-17A and TNF-α as potential biomarkers for acute respiratory distress syndrome and mortality in patients with obesity and COVID-19.

Coronavirus disease 2019 (COVID-19) was declared a pandemic and international health emergency by the World Health Organization. Patients with obesity with COVID-19 are 7 times more likely to need invasive mechanical ventilation than are patients without obesity (OR 7.36; 95% CI: 1.63-33.14, p = 0.021). Acute respiratory distress syndrome (ARDS) is one of the main causes of death related to COVID-19 and is triggered by a cytokine storm that damages the respiratory epithelium. Interleukins that cause the chronic low-grade inflammatory state of obesity, such as interleukin (IL)-1ß, IL-6, monocyte chemoattractant peptide (MCP)-1, and, in particular, IL-17A and tumour necrosis factor alpha (TNF-α), also play very important roles in lung damage in ARDS. Therefore, obesity is associated with an immune state favourable to a cytokine storm. Our hypothesis is that serum concentrations of TNF-α and IL-17A are more elevated in patients with obesity and COVID-19, and consequently, they have a greater probability of developing ARDS and death. The immunobiology of IL-17A and TNF-α opens a new fascinating field of research for COVID-19.