As has been reported for other COVID-19 patients (31), this COVID-19 cohort presented with a clinical inflammatory syndrome. C reactive protein (CRP) was elevated in over 90% of subjects and LDH and D-dimer were increased in the vast majority, whereas ferritin was above normal in ~75% of COVID-19 patients (Fig. 1B and fig. S1B). Similarly, troponin and NT-proBNP were increased in some patients (fig. S1B). In a subset of patients where it was measured, IL-6 levels were normal in 5 patients, moderately elevated in 5 patients (6-20 pg/ml), and high in 31 patients (21-738 pg/ml) (fig. S1B). Although white blood cell counts (WBC) were mostly normal, individual leukocyte populations were altered in COVID-19 patients (Fig. 1B). A subset of patients had high PMN counts (fig. S1B) as described previously (8, 32) and in a companion study (33). Furthermore, approximately half of the COVID-19 patients were clinically lymphopenic (ALC <1 THO/ul, Fig. 1B). In contrast, monocyte, eosinophil, and basophil counts were mostly normal (Fig. 1B and fig. S1B).