Abstract
The aim of this study is to evaluate the potential of lymphocytes as biomarkers to predict the decline of coronavirus disease 2019 (COVID-19). Lymphocytes were counted in 164 moderate COVID-19 patients in Shenzhen, China. Among the moderate infected patients, 12.2% (20/164) progressed to severe cases after admission. Compared with the stable patients, the counts of lymphocytes, both total T lymphocytes and CD4+ T lymphocytes, in the severe patients, were lower. The aggravation of moderate infected patients was significantly associated with lymphocyte count (hazard ratio [HR] = 0.91; 95% confidence interval [CI]: 0.84-0.99), total T lymphocyte count (HR = 0.91; 95% CI: 0.84-0.99), and CD4+ T lymphocyte count (HR = 0.91; 95% CI: 0.85-0.98). Total T lymphocytes and CD4+ T lymphocytes could be important biomarkers to evaluate the risk of aggravation for moderate infected COVID-19 patients. The patients with low percentages of total T lymphocytes and CD4+ T lymphocytes need more attention.