IL6 and COVID-19: Moreover, there were significant differences in NC, LC, CRP and IL-6 between the mild group and the severe group, which was consistent with findings reported by Liu Y et al., suggesting that patients infected with COVID-19 may suffer from multiple organ dysfunction.10,11 Previous studies have shown that increased serum levels of pro-inflammatory cytokines were associated with lung inflammation and lung injury in patients.12-14 Our study found that the level of IL-6 in the severe group was significantly higher than that in the mild group.