Table 2.

Serum levels of IgA, normalized and total autoantigen (Gd-IgA1), IgG, normalized and total IgG autoantibody, and normalized and total IgA autoantibody in controls (healthy, diseased, and combined) and in IgAN patients

Healthy ControlsDiseased ControlsP Value(t and U Tests)Combined ControlsAll IgAN PatientsP Value (t and U Tests)
Patients (n)30306097
IgA (mg/ml)2.20 (0.76)2.01 (0.81)NS2.10 (0.78)2.88 (1.38)0.0001
2.09 (0.75–4.12)1.98 (0.79–3.85)NS2.03 (0.75–4.12)2.68 (0.49–8.01)0.0003
Gd-IgA1 (% HAA)31.3 (9.1)36.1 (15.3)NS33.7 (12.7)33.1 (12.4)NS
29.5 (15.4–57.0)31.3 (15.9–86.5)NS30.8 (15.4–86.5)31.5 (10.0–76.5)NS
Gd-IgA1 (U/ml)68.2 (26.0)71.5 (41.1)NS69.9 (34.1)92.6 (49.4)0.002
65.4 (16.7–112.3)62.0 (25.3–184.3)NS63.4 (16.7–184.3)84.4 (10.0–267.5)0.003
IgG (mg/ml)11.01 (2.64)9.94 (4.05)NS10.47 (3.43)10.32 (3.79)NS
10.54 (6.69–18.41)9.81 (4.88–21.58)NS9.92 (4.88–21.58)10.00 (1.33–25.77)NS
IgG autoantibody (OD/0.5 µg)1.172 (0.242)1.300 (0.304)NS (0.08)1.236 (0.280)1.483 (0.643)0.006
1.195 (0.85–1.54)1.272 (0.76–2.00)NS1.255 (0.76–2.00)1.490 (0.63–3.01)0.07 (NS)
IgG autoantibody (U/ml)25.60 (7.28)25.16 (10.58)NS25.38 (9.01)30.79 (19.04)0.04
24.34 (14.88– 41.96)24.55 (12.04–60.97)NS24.40 (12.04–60.97)26.03 (5.72–91.62)NS
IgA autoantibody (OD/1 µg)0.549 (0.234)0.770 (0.638)NS (0.08)0.660 (0.489)0.748 (0.451)NS
0.458 (0.29–1.13)0.556 (0.24–2.84)NS0.493 (0.24–2.84)0.589 (0.21–2.31)NS (0.06)
IgA autoantibody (U/ml)1.29 (0.91)1.55 (1.37)NS1.42 (1.16)2.33 (2.02)0.002
0.93 (0.28–3.45)0.90 (0.19–5.99)NS0.91 (0.19–5.99)1.78 (0.12–10.63)0.002
  • Data are mean (SD) or median (range). NS, not statistically significant.