[Value of basophil studies in the diagnosis of drug allergies]

Mastocytes and basophils are the two cell populations involved in the reactions seen during drug allergies. The testing of basophils is the only and simplest way of studying sensitization in the IgE system by a drug antigen, especially when the skin tests cannot be carried out. This study is carried out in two steps: straight after the drug-induced accident, where a basophil count will give an idea of its allergic origin; and some time after the accident, where the human basophil degranulation test (H.B.D.T.) helps to identify in over 50 p. 100 of cases the responsible drug. The basophil count and H.B.D.T. techniques are then described. The authors present their own results. In a study by H.B.D.T. of 908 patients with a drug allergy, 53.2 p. 100 had positive test; 57.6 p. 100 of 33 cases who presented an anaesthetic accident had a positive H.B.D.T.