Basophil sensitisation in idiopathic nephrotic syndrome.

The degranulation of basophils in the presence of a specific allergen (human basophil degranulation test, HBDT) is an index of IgE-dependent cellular response and it was tested in 46 unselected idiopathic nephrotic syndrome (INS) patients with or without atopic manifestations. 28 of the INS patients had "minimal change" nephrotic syndrome (MCNS) and 18 had focal segmental glomerular sclerosis (FSGS). 29 patients with different types of primary glomerulonephritis (GN) and 11 healthy donors acted as controls. The HBDT was positive in 16 (57%) of 28 MCNS and in 14 (77.8%) of 18 FSGS patients. Only 5 (17.2%) of 29 GN and 1 (6%) of 11 blood donors exhibited positive HBDT. House dust was the commonest allergen to which MCNS and FSGS subjects were sensitive, whereas sensitivity to grass pollen, moulds, and animal danders was less common. 8 MCNS and 8 FSGS subjects were sensitive to house dust plus another allergen. 4 MCNS and 1 FSGS patient had fewer than 5/microliters basophils; 4 of these 5 patients were having a relapse of their nephrotic syndrome at the time. The demonstration of enhanced IgE-basophil sensitisation in INS patients suggests than an anaphylactic process plays a part in the pathogenesis of INS.