A literature review outlined the main risk factors for severe clinical progression and adverse outcomes in COVID-19 patients, which included coagulation disorders, leukocytosis, lymphopenia, decreased eosinophils, and elevated levels of aspartate aminotransferase, BUN creatine kinase, troponin I, CRP, PCT, and Interleukin-6. This evidence concerns the gene IL6 and lymphopenia.