Our data confirmed that baseline HE4 level demonstrated a moderate but statistically significant positive correlation with general inflammatory markers, such as CRP, IL-6, and WBC counts, certain prognostic markers of COVID-19, e.g., total LDH activity, ferritin, and serum ACE2 activity [19] and finally some important clinical parameters including the SOFA score and the degree of lung manifestation based on chest CT scanning (Table 2). The gene discussed is ACE2; the disease is COVID-19.