COVID-19 infection induces readily detectable morphological and inflammation-related phenotypic changes in peripheral blood monocytes, the severity of which correlate with patient outcome

Dan Zhang; Rui Guo; Lei Lei; Hongjuan Liu; Yawen Wang; Yili Wang; Tongxin Dai; Tianxiao Zhang; Yanjun Lai; Jingya Wang; Zhiqiang Liu; Aili He; Michael O'Dwyer; Jinsong Hu

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03. 24.20042655 doi: medRxiv preprint 8 into the lungs and other affected organs. While morphological examination of peripheral blood films revealed somewhat larger, atypical, vacuolated monocytes, these findings are not very specific. We have shown that simple assessment of FSC by flow cytometry in the context of COVID-19 infection can rapidly identify those patients with an increasing proportion of large, activated, IL-6 and TNF secreting monocytes, who have severe disease and are at greatest risk of ICU admission. In contrast, patients with a high proportion of normal monocytes have better prognosis with earlier recovery and discharge from hospital. These findings appear to be relatively specific for COVID-19 as we have not seen a similar pattern in patients with other viral illnesses, such as H1N1 influenza, HIV, or Hantaanvirus.