C4A and systemic lupus erythematosus: Previous studies among SLE patients have also reported the strong association of urine NGAL [19–21] and serum C3 complement in active LN [28, 29], but data from the Aspreva Lupus Management Study (ALMS) study indicated that only baseline C4 complement level, and early normalization of complement but not C3 complement independently predicted renal response to therapy at 6 months [30].