Diagnosis of immediate-type beta-lactam allergy in vitro by flow-cytometric basophil activation test and sulfidoleukotriene production: a multicenter study

• Published in: Journal of investigational allergology & clinical immunology Vol. 19; no. 2; pp. 91 - 109
• Main Authors: De Week, A L, Sanz, M L, Gamboa, P M, Aberer, W, Sturm, G, Bilo, M B, Montroni, M, Blanca, M, Torres, M J, Mayorga, L, Campi, P, Manfredi, M, Drouet, M, Sainte-Laudy, J, Romano, A, Merk, H, Weber, J M, Jermann, T M
• Format: Journal Article
• Language: English
• Published: Spain 2009
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Basophil Degranulation Test; beta-Lactams - administration & dosage; beta-Lactams - immunology; Cell Separation; Drug Hypersensitivity - blood; Drug Hypersensitivity - diagnosis; Drug Hypersensitivity - immunology; Drug Hypersensitivity - physiopathology; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Humans; Immunoglobulin E - blood; Leukotrienes - immunology; Leukotrienes - metabolism; Male; Middle Aged; Sensitivity and Specificity; Skin Tests; Sulfides - immunology; Sulfides - metabolism
• ISSN: 1018-9068

This multicenter study aimed to evaluate the diagnostic value of 2 cellular tests based on basophil reactivity--the basophil activation test (BAT, Flow-CAST) and the sulfidoleukotriene release assay (CAST-ELISA)--in immediate-type beta-lactam allergy, particularly in patients with a clinical history of allergy and a negative skin test result. In a multicenter study encompassing 10 European centers, 181 patients with a history of immediate-type beta-lactam allergy, and 81 controls, we evaluated the diagnostic efficiency of specific IgE determinations and of 2 cellular tests based on basophil reactivity, the BAT and the sulfidoleukotriene release assay. With Flow-CAST, sensitivity varied for individual beta-lactam allergens from 16% for penicilloyl-polylysine to 33% for amoxicillin, reaching 50% when all 5 allergens were considered. In beta-lactam-allergic patients with negative skin test results (22.8%), Flow-CAST showed positive results for at least 1 of the 5 allergens in 37%. Specificity varied from 89% to 97%, depending on the allergens used. In CAST-ELISA, the overall sensitivity in skin test-positive patients was 41.7%; in patients with negative skin test results it was 27.9%. Both tests were not absolutely correlated, so that when all the results were considered together, sensitivity increased to 64.3% and specificity varied for both tests combined from 73% to 92%. In contrast, specific IgE determinations in the same population yielded a lower sensitivity (28.3%). A diagnostic algorithm including skin tests and specific IgE, followed by cellular tests in negative patients and controlled challenge enabled us to confirm beta-lactam allergy in 92% of cases. This procedure would also allow us to avoid two-thirds of the required controlled challenges.