Zhang W, Li L, Liu J, et al. The characteristics and predictive role of lymphocyte subsets in COVID-19 patients [published online ahead of print, 2020 Aug 3]. Int J Infect Dis. 2020;S1201-9712(20)30514-2. doi:10.1016/j.ijid.2020.06.079

Objective: To investigate the characteristics and predictive roles of lymphocyte subsets in COVID-19 patients.

Method: We evaluated lymphocyte subsets and other clinical features of COVID-19 patients and analysed their potential impacts on COVID-19 outcomes.

Results: 1. Lymphocyte subset counts in the peripheral blood of patients with COVID-19 were significantly reduced, especially in patients with severe disease. 2. In patients with non-severe diseases, the time from symptom onset to hospital admission was positively correlated with total T cell counts. 3. Among COVID-19 patients who did not reach the composite endpoint, lymphocyte subset counts were higher than in patients who had reached the composite endpoint. 4. The Kaplan-Meier survival curves showed significant differences in COVID-19 patients, classified by the levels of total, CD8+ and CD4+ T cells at admission.

Conclusion: Our study shows that the total, CD8+ and CD4+ T cell counts in patients with COVID-19 were significantly reduced, especially in patients with severe disease. T lymphocyte subsets were significantly associated with a higher occurrence of composite endpoint events. These subsets may help identify patients with a high risk of composite endpoint events.