Abstract: Objective To analyze the relationship between urinary angiotensinogen(AGT) and the formation of crescent in IgA nephropathy(IgA N) patients. Methods Between March 2011 and June 2013, 45 patients who were diagnosed with IgA nephropathy by renal biopsy in the Peking University Third Hospital were chosen in the study. Enzyme linked immunosorbent assay ( ELISA ) was applied to detect the levels of urinary AGT. Crescent index was calculated and correlation analysis was processed between urinary AGT and crescent index. Results T he urinary level of AGT in IgA N group increased significantly compared with that of control group (212.3±276.1 vs. 6.6 ± 4.9 μg/g, p<0.05). The level of urinary AGT in IgA N patients with crescent formation increased compared with that of non crescent group (272.3±329.7 vs.143.6±187.2μg/g, p<0.05).The level of urinary AGT of index o f crescent≥10% group increased compared with that of the index of crescent <10% group (375.8±391.9 vs. 201.3±186.3 μg/g, p<0.05). T he level of urinary AGT was positively correlated with index o f crescent(r=0.483，p=0.001) and 24-h urine protein (r=0.618, p=0.000), and negatively correlated with serum albumin(r= - 0.535, p=0.000).Conclusion The levels of urinary AGT may reflect the renal tissue of crescent formation in IgA N patients.

Key words: IgA nephropathy, Crescent, Proteinuria, Urinary angiotensinogen, renin angiotensin system