C4A and systemic lupus erythematosus: Mean SCr of SLE patients was 0.89 ± 0.17 mg/dL, eGFR was 81 ± 19 mL/min/1.73 m2, Uprot 680 ± 5.600 mg/24 h, and C3 and C4 levels at time of evaluation were 74.65 (29.9–127) mg/dL and 15.7 (3.86–27.2) mg/dL, respectively.