C3 and lupus nephritis: Categorical variables and adverse event data were presented as N and percentage (%), N: number, BMI: body mass index, LN: lupus nephritis, CRP: C reactive protein, ESR: erythrocyte sedimentation rate, C3: complement C3, dDNA: double stranded DNA, HCQ: hydroxy chloroquine, MMF: mycophenolate mofetil, MPA: mycophenolic acid, SLEDAI: SLE Disease Activity Index