IgG3 levels in patients with chronic membranoproliferative glomerulonephritis.

In patients with membranoproliferative glomerulonephritis a higher proportion of the serum IgG was IgG3 than in normal subjects, patients with other types of renal disease, or patients with non-renal diseases. Though having a lower mean serum IgG than normal their mean serum IgG3 was raised. This tendency was more pronounced in the hypocomplementaemic patients with the disorder than in those with a normal level of serum complement.