Is the serological bee/vespula venom-specific IgE ratio supplemented by component-resolved diagnostics a reliable alternative to skin testing for hymenoptera venom allergy?

Background A reliable diagnosis of hymenoptera venom allergy is based on medical history, skin tests, and serological immunoglobulin E (IgE) determination. Over the past 10 years, component-resolved diagnostics (CRD) have gained in importance, and new strategies for interpreting serological double sensitization have been introduced with the bee/vespula venom-specific IgE ratio. Objectives The aim was to examine whether the bee/vespula venom-specific IgE ratio supplemented by CRD can be a reliable alternative to skin testing. Methods In a student project, the guideline algorithm for serological diagnostics was supplemented with the sIgE ratio (≥ 5:1) and tested in a simulation using anonymized data from a retrospective study (Fischer et al.). A partial data set of 375 cases with complete CRD and documented prick and intradermal test results was selected for the simulation. The performance of the algorithm was evaluated by a post hoc comparison of the algorithmic therapy recommendations with the allergen immunotherapies (AIT) actually implemented in the clinic. Results The simulation yielded 48.5% monosensitizations and 49.9% double sensitizations. In 56.3% of the double sensitizations, the ratio ≥ 5:1 indicated a dominant sensitization, which was classified as a mono-allergy. The therapies suggested by the algorithm corresponded to the clinically implemented AIT in 91% of cases; overall, the correspondence was 89.7%. While the algorithm predicted double AIT in 10% of cases, this was only clinically implemented in 2.7% of cases, with anamnestic details on sting circumstances and diagnostic certainty influencing the decision. Conclusion Standardized serological diagnostics with bee/vespula venom-specific IgE ratio and CRD provide high diagnostic precision and comprehensively demonstrate the progress made over the last 10 years. Skin tests remain a medically useful and valuable part of diagnostics, especially in cases of double sensitization.