Immunoglobulin E antibodies to rocuronium: a new diagnostic tool

Area of Science:

• Allergy and Immunology
• Pharmacology
• Clinical Diagnostics

Background:

• Diagnosing allergies to neuromuscular blocking agents like rocuronium can be complex.
• The study aimed to evaluate the diagnostic value of immunoglobulin E (IgE) quantification using ImmunoCAP for rocuronium allergy.
• It also investigated the predictive capability of IgE inhibition tests for cross-reactivity between neuromuscular blocking agents.

Purpose of the Study:

• To assess the utility of ImmunoCAP for quantifying specific IgE against rocuronium.
• To determine if IgE inhibition tests can predict clinical cross-reactivity among neuromuscular blocking agents.
• To explore the impact of elevated total IgE on diagnostic accuracy.

Main Methods:

• Inclusion of 25 patients with confirmed rocuronium allergy and 30 control individuals.
• Analysis of sera for specific IgE to rocuronium, suxamethonium, morphine, and pholcodine.
• Assessment of cross-reactivity using IgE inhibition and skin tests, with special analysis for sera containing high total IgE (>1,500 kU/l).

Main Results:

• Specific IgE testing showed high sensitivity for morphine (88%) and pholcodine (86%), and good sensitivity for rocuronium (68%) and suxamethonium (60%).
• Specificity was excellent (100%) for suxamethonium, morphine, and pholcodine, and high (93%) for rocuronium.
• Adjusted thresholds via ROC analysis improved sensitivity significantly (e.g., rocuronium 92%) while maintaining specificity; elevated total IgE levels were found to interfere with assay specificity.
• IgE inhibition tests did not reliably predict clinical cross-reactivity.

Conclusions:

• The rocuronium ImmunoCAP assay is a dependable method for diagnosing rocuronium allergy when an appropriate, assay-specific decision threshold is employed.
• IgE assays targeting ammonium epitopes are validated as reliable tools for diagnosing rocuronium allergy.
• High levels of total IgE can negatively influence the specificity of these diagnostic assays.