C3 and systemic lupus erythematosus: Notably, 36.0% of the SLE patients tested positive for anti-dsDNA antibodies, 74.7% were positive for antinuclear antibodies (ANA), 30.0% exhibited decreased levels of complement component C3, 50.7% showed decreased levels of complement component C4, 38.0% had elevated erythrocyte sedimentation rates (ESR), 13.3% presented with increased high-sensitivity C-reactive protein (hs-CRP) levels, and 56.6% had rash, and 51.6% had nephritis.