IL2 and systemic lupus erythematosus: The baseline median disease activity index of SLEDAI-2K (Systemic Lupus Erythematosus Disease Activity Index 2000) of IL-2 group was higher than that of non-IL-2 group (5 v.s. 2 points, P-value < 0.001), in line with a higher frequency of active lupus nephritis (LN) in IL-2 group (33.3%, 73/219) than non-IL-2 group (12.3%, 55/446) (P-value < 0.001) (Table 1).