AZU1 and COVID-19: Among the common neutrophil activation signatures that is shared by COVID-19 patients and those with other acute inflammatory states, 11 genes (ARG1, AZU1, CD177, CEACAM8, CTSG, DEFA4, ELANE, LCN2, MCEMP1, MMP8, and OLFM4) commonly dysregulated in COVID-19 and HLH specifically stratified COVID-19_ICU from COVID-19_nonICU patients.