The underlying changes and predicting role of peripheral blood inflammatory cells in severe COVID-19 patients: a sentinel?

•Lymphopenia and eosinopenia might be predictors of disease severity in COVID-19.•Lymphopenia and eosinopenia might be predictors of disease progression in COVID-19.•Clinical classification-severe type is the dependently risk factor for alteration of PBICs.•PBICs might be a sentinel, and it deserves attention during COVID-19 management.