Correlation analysis showed that plasma CFH levels inversely correlated with initial serum creatinine, Birmingham Vasculitis Activity Score (BVAS), proportion of total crescents and cellular crescents in renal specimens, and circulating levels of C3a, C5a and Sc5b-9, meanwhile positively correlated with estimated glomerular filtration rate (eGFR), hemoglobin levels and circulating levels of C3. Here, C3 is linked to vasculitis.