The results showed that the AUC of ESR, dsDNA, IgG, C3 and C4 were all greater than 0.7, and the AUC of IgG was 0.891 (P< 0.01), which proved that it has good diagnostic value for SLE hematological system involvement (Table 3 and Figure 1). Here, C4A is linked to systemic lupus erythematosus.