Comparing Basophil Activation Test and Specific IgE Assay in the Diagnosis of Allergy to Penicillin G and Ibuprofen

The risks associated with in vivo tests in the diagnosis of immediate drug hypersensitivities result in evaluating alternative in vitro tests, such as the Basophil Activation Test (BAT). This pilot study aimed to set up a BAT and compare it with a specific Immunoglobulin E (sIgE) assay for penicillin G and Ibuprofen in patients with immediate hypersensitivity to β-lactams or nonsteroidal anti-inflammatory drugs (NSAIDs). Eleven subjects with a clear history of immediate hypersensitivity to one of the β-lactams (n=5), the NSAIDs (n=3), or both (n=3) entered this study. BAT and sIgE assays were performed regarding the patient's history. The most frequent manifestations were angioedema, shortness of breath, urticaria, and nausea. Eight patients had anaphylactic reactions. The results presented a positive BAT for penicillin G and one for Ibuprofen. Moreover, three patients with a history of the β-lactams reaction demonstrated positive sIgE to β-lactams in the ImmunoCAP. Despite a lack of agreement between the positive results of the BAT and sIgE assay, five patients were identified by one of these methods. Despite positive BAT and sIgE results in two and three patients, respectively, the risks, high cost, and time-consuming nature of drug challenges render these tests valuable for reducing the number of patients who are candidates for a drug challenge.