- D1.518 - Patient Phenotypes in Prolonged Immunotherapy for Hymenoptera Venom

Venom Immunotherapy (VIT) is an effective treatment for preventing anaphylaxis in patients with a history of systemic reactions and confirmed sensitization. The aim of this review is to analyze data from patients undergoing VIT for more than 5 years. According to international guidelines, VIT is prolonged in patients with a history of more severe reactions, beekeepers, and those who experience systemic reactions during therapy.

We conducted a review of the medical records of 228 patients who underwent VIT at the Allergy Department of Laiko Hospital from November to December 2024.

A total of 135 patients were included who had undergone VIT for more than 5 years. The median age was 61.5 (17-87) years and 105 were male. The vast majority (119 patients, 88.8%) had a history of more severe reactions (Mueller III/IV), of whom 81 (68,1%) were sensitized to bee venom and 98 (82,4%) to common wasp venom, with this difference being statistically significant (p≈0.02). Thirty-six patients (26.9%) had a relationship with beekeeping, either professional or amateur, with a statistically significant predominance (p<0.01) of bee sensitization (34 patients, 94.4%) compared to common wasp sensitization (20 patients, 55.6%). The venom used for immunotherapy was bee venom in 71 patients (53%) and common wasp in 70 patients (52.2%). Systemic reactions during the initiation or maintenance of VIT occurred in 34 patients (25.4%), most of whom were receiving bee VIT (26 patients, 76.5%) while 30 patients had a history of more severe reactions (88.2%). Sensitization to common wasps was more frequent (105 patients, 78.4%), followed by bee (94 patients, 70.1%) without a statistically significant difference (p>0.05), while 72 patients were sensitized to both.

The results of this study population are consistent with international literature data, specifically the more frequent bee sensitization among beekeepers and the association of bee immunotherapy and/ or history of more severe reactions with reactions during VIT. An exception is the association of common wasp sensitization with a history of more severe reactions.