Fig. 1

sP-selectin as a marker of COVID-19 severity and a predictor of intubation and death. a Soluble P-selectin was measured in plasma from patients from COVID-19 patients from Cohort 1 and plotted according to severity grade (moderate, severe or critical disease) or from non-COVID-19 septic shock patients. Groups: mild-to-moderate (n = 35), severe (n = 10), critical (n = 15), non-COVID-19 septic shock (n = 29). *p < 0.05 (Kruskal–Wallis test followed by Dunn’s post-test). b, c, sP-selectin correlation with CRP levels (b) or platelet counts (c). r and p values were determined using Spearman’s correlation test. d, e, sP-selectin normalized to platelet counts as a predictor of intubation (d) or death (e). ROC curves with area under the curve (AUC) and associated p values are shown. Optimal threshold was determined by maximization of Youden’s index, and represented by a dashed line. Bar graphs indicate the number of patients in each group depending on normalized sP-selectin levels with respect to the optimal threshold. Groups: no intubation (n = 31), intubation (n = 29), no death (n = 43), death (n = 17)