This systematic review identified several biomarkers that may potentially identify cases at risk for severe disease or death. 

Researchers conducted a review of studies reporting on laboratory abnormalities in patients with COVID-19. They focused on two outcomes, severity and mortality. They identified 21 studies, totaling 3377 patients and 33 laboratory parameters. Eighteen of them compared laboratory findings between patients with severe and non-severe cases, and three compared survivors and
non-survivors.

Patients with severe and fatal disease had significantly increased WBC, and decreased lymphocyte and platelet counts. Biomarkers of inflammation, cardiac injury, muscle injury, liver function, kidney function, and coagulation measures were also elevated. Interleukins 6 (IL-6) and 10 (IL-10) and serum ferritin were strong indicators of severe disease.