• Athina L Van Gasse, Jessy Elst, Chris H Bridts, Christel Mertens, Margaretha Faber, Margo M Hagendorens, Luc S De Clerck, Vito Sabato, and Didier G Ebo.
• Department of Immunology, Allergology, Rheumatology, Faculty of Medicine and Health Sciences, University of Antwerp - Antwerp University Hospital, Antwerp, Belgium; Department of Paediatrics, Faculty of Medicine and Health Sciences, University of Antwerp -Antwerp University Hospital, Antwerp, Belgium.
• J Allergy Clin Immunol Pract. 2019 Mar 1; 7 (3): 998-1003.

BackgroundThe neuromuscular blocking agent (NMBA) rocuronium is a relevant cause of perioperative hypersensitivity (POH) with a significant risk of diagnostic error. Recently, it has been suggested to reclassify hypersensitivity to NMBA as type A reactions resulting from off-target occupation of the nonimmune MRGPRX2 receptor.ObjectiveTo investigate whether basophil activation experiments can benefit diagnosis and add to the insights in the pathomechanisms of rocuronium hypersensitivity.MethodsA total of 140 patients with a suspected POH to rocuronium in whom peak tryptase was available had complete diagnostic workup for all potential culprits including triple confirmatory testing with skin tests, basophil activation test (BAT), and quantification of specific IgE (sIgE) antibodies to rocuronium and morphine. To further analyze the clinical relevance of sIgE antibodies, quantitative basophil inhibition experiments were performed by coincubation of the cells with rocuronium and morphine, an opiate known to harbor a substituted ammonium structure.ResultsDiagnosis of rocuronium hypersensitivity was established in 72 of 140 patients (51.4%), of whom 65 (90.3%) demonstrated mast cell activation. Of the 72 patients, 64 displayed a positive skin test, 8 (11.1%) had their diagnosis documented only by BAT. Coincubation of morphine and rocuronium induced a dose-dependent inhibition of BAT with rocuronium that was restricted to 4 of 6 patients with IgE reactivity to rocuronium and/or morphine.ConclusionsBAT can benefit diagnosis of rocuronium hypersensitivity. As basophils barely express MRGPRX2 and BAT rocuronium can be inhibited by morphine, we believe that hypersensitivity to rocuronium still mainly results from IgE/high-affinity receptor for sIgE (FcεRI)-dependent effector cell activation. However, it cannot be excluded that in a few patients rocuronium hypersensitivity results from off-target occupation of the MRGPRX2 receptor.Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

34 keywords...

hide…