Secretory IgA are elevated in both saliva and serum of patients with various types of primary glomerulonephritis.

Secretory immunoglobulin A (IgA) was determined by means of an enzyme-linked immunosorbent assay (using as capture antibody an MoAb specific for secretory component) in saliva and serum from 46 patients with IgA mesangial nephritis (IgAGN), 36 with an idiopathic nephrotic syndrome (INS), 30 with an idiopathic membranous nephropathy (MGN) and 40 healthy controls. Secretory IgA levels were elevated in both saliva and serum of patients with primary glomerulonephritis (P 0.05; Mann-Whitney test). We conclude that the mucosal immune system is activated in forms of glomerulonephritis other than IgAGN.