Abstract: Objective To observe the relationship between serum Gd-IgA1 level and clinicopathological features as well as hormone response in patients with IgA nephropathy. Methods The perspectively review identified 40 patients with IgAN were confirmed by renal biopsies as experimental group, and these patients have been treated with hormones therapy in our department. And 20 patients with membranous kidney disease and 20 normal healthy controls in physical examination center of our hospital were regarded as control groups. The level of Gd-IgA1 in all serum samples and the general data of patients, renal function, 24 h urinary protein quantity and IgA level were statistically analyzed. The pathological sections of IgA nephropathy were graded by Haas, and the results of grading were statistically analyzed. Results Compared with normal group (3.56±0.30) mg/L and disease control group (3.40±0.41) mg/L, the level of serum Gd-IgA1 in patients with IgA nephropathy（9.44±0.74）mg/L was higher, and was positively correlated with 24 h urinary protein quantity and renal pathological grade, and the difference was statistically significant （P<0.05）. After 1 month of hormonal therapy, the level of Gd-IgA1 in IgAN patients was lower than before（P<0.05）. Conclusion The level of serum Gd-IgA1 was positively correlated with the severity of IgA nephropathy, and decreased after hormone treatment, suggesting that serum-Gd-IgA1 could serve as a predictor of renal outcomes in IgAN. Thus, Gd-IgA1 could be significant biomarker for patients with IgAN.

Key words: IgA nephropathy, Galactose-deficient IgA1(Gd-IgA1), Corticosteroid therapy, Biomarker