Evaluation of the human basophil degranulation test using the commercially available Baso-kit as a test of immediate-type hypersensitivity in hay-fever sufferers.

The basophil degranulation test (BDT) has failed to gain popular acceptance as a test of immediate-type hypersensitivity since its introduction in clinical medicine in 1961. Recent modification of this technique, however, seemed to have increased its reliability. We have studied a group of twenty-five hay-fever sufferers and a similar age- and sex-matched group of healthy controls to compare the sensitivity of a newly available commercial BDT kit (Baso-kit, Laboratoire des Stallergenes) with specific serum IgE levels and skin-prick tests to meadow-grass pollen. A quantitative correlation was found between the positive BDT (greater than 30% degranulation) and the skin tests, whereas only a qualitative relationship was obtained with specific IgE concentrations. The BDT also identified two subpopulations of responders and non-responders among a third group of hay-fever subjects who had previously been hyposensitized to mixed grass pollen. We conclude that the modified BDT provides a worthwhile addition to the in vitro testing of immediate-type hypersensitivity states.