Parmaksız et al. demonstrated a prognostic relationship between uric acid levels and COVID-19.16 In their study, Toori et al. showed that the neutrophil-lymphocyte ratio (NLR) could be a biomarker associated with disease severity and mortality in COVID-19.17 Considering these results, PSA should also be considered as a potentially useful prognostic marker in COVID-19. Here, KLK3 is linked to COVID-19.