RESULTS: Patients with secondary IgAN presented with higher plasma
Gd-IgA1 levels compared to healthy controls (median, 354.61 U/ml; interquartile range [IQR], 323.93, 395.57 U/ml vs. median, 303.17 U/ml; IQR, 282.24, 337.92 U/ml, P < 0.001) or patients with other
kidney diseases (median, 314.61 U/ml; IQR, 278.97, 343.55 U/ml, P < 0.001). A similar trend was observed in plasma
IgA/
IgG immune complexes or
IgA1. There were no differences between secondary and primary IgAN in plasma
Gd-IgA1 levels (median, 378.54 U/ml; IQR, 315.96, 398.33 U/ml, P = 0.700) and IgA1-IgG complex levels (median, 18.76 U/ml; IQR, 14.51, 22.83 U/ml vs. median, 19.11 U/ml; IQR, 13.21, 22.37 U/ml, P = 0.888). Co-localized
IgA1 and
Gd-IgA1 of both secondary and primary IgAN indicated that they both share the feature of
Gd-IgA1 deposits on the glomerular mesangium.
CONCLUSION: