IL-6 Gene (174G/C) Single Nucleotide Polymorphism as an Indicator of COVID-19 Severity in Egyptian Patients

Abstract

Background: The viruses' direct damage plays a part in the disease's beginning, the cytokine storm brought on by COVID-19 is crucial to the emergence of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). This study aimed to investigate the correlation between IL-6 and its IL- 6 gene (174G/C) single nucleotide polymorphism with the pathogenesis of COVID-19 severity in Egyptian patients.
 Materials & Methods: Egyptian patients proved to be COVID-19 positive were classified into three groups; Group 1 (mild cases), Group 2 (moderate cases) and Group 3 (severe and critical cases). Complete blood count, liver function tests, renal function tests, CRP, and coagulation profile, serum ferritin, D-dimer, procalcitonin, lactate dehydrogenase and detection of serum interleukin 6 levels, and IL-6 gene polymorphism were investigated for all enrolled 135 patients.
 Results: There was a significant decrease of platelets count of group II & III as compared to group I. There was a significant increase of total leucocytic count, CRP, ferritin, D – dimer, procalcitonin, blood urea and IL6 of group III as compared to group I & II. There was significant decrease of relative lymphocyte counts % of group III as compared to group I & II. There was significant increase of LDH of group II & III as compared to group I. There were no statistically significant differences were found as regards hemoglobin, SGPT, SGOT, serum creatinine and I.N.R & interleukin-6 174G/C distribution of the different studied groups.
 There were positive correlations between serum interleukin 6 levels and CORAD scores, ferritin count, LDH, and D- dimer, and blood urea, and only a negative correlation with relative lymphocyte count %.
 Conclusion: interleukin-6 plays an important role in the pathogenesis of COVID-19. In addition, it reveals that serum IL6 can be used as a predictor of disease severity in COVID-19 patients, but interleukin-6 174G/C genotype distribution cannot be used as a predictor of disease severity in COVID-19 Egyptian patients.