The Clinical Importance of Component-Based Diagnostic Test in Patients Planned for Venom Immunotherapy

INTRODUCTION: Venom immunotherapy (VIT) is the most effective treatment approach for preventing severe systemic reactions caused by hymenoptera stings. In some cases, the detection of specific immunoglobulin E (IgE) positivity for both honeybee and wasp venoms can create diagnostic and therapeutic challenges. In this study, we aimed to evaluate the effectiveness of the Immulite 2000 3g Allergy component-based diagnostic test (CBDT) in determining true sensitization in patients with dual venom positivity who were scheduled for VIT. METHODS: In this prospective study, 66 patients who presented to the Immunology and Allergy Diseases outpatient clinic between January 2019 and December 2024 with a history of systemic reaction following a bee sting and who were indicated for VIT were evaluated. RESULTS: The mean age of the patients was 46.3 ± 12.9 years, with a male predominance. Honeybee stings were the most common (50%). Forty-two patients had single-venom sensitization, while 22 had specific IgE positivity for both Apis mellifera and Vespula vulgaris. According to the CBDT results, 6 of the 22 patients had dual sensitization, while 7 patients had sensitization only to Vespula. Patients with indeterminate venom sensitization had higher Api m 1/Ves v 5 specific IgE ratios. CONCLUSION: In our study, using the Immulite 2000 3g Allergy CBDT results, venom sensitization could not be clearly determined in 41% of patients with dual sensitization to venom allergens, and true double sensitization was identified in only 27% of these patients. Therefore, we suggest that including additional species-specific antigens (especially Ves v 1) alongside in the Immulite 2000 3g Allergy CBDT panel could improve the detection of true sensitization. Furthermore, when supported by accurate and reliable clinical history, a specific IgE Api m 1/Ves v 5 ratio greater than 5 can represent a significant and useful hypothesis. However, further studies are needed to confirm this hypothesis.