- D1.515 - Occupational Exposure of Patients Allergic to Hymenoptera Venom

Hymenoptera venom allergy is a significant health risk that can occur in the workplace. This study aims to characterize the demographic, clinical, and therapeutic profile of patients who suffer allergic reactions to stings at work.

We performed a retrospective descriptive study of patients allergic to hymenoptera venom who attended the HUFA Allergy Unit between 2021 and 2025. Patients who had suffered an allergic reaction in the workplace were selected, and demographic and occupational data, personal history, clinical manifestations, etiological diagnosis, and therapeutic management were analyzed.

A total of 75 patients were included, most of whom (86.8%) were allergic to wasps. Of these, 12 patients (16%) were stung in the workplace.

In the occupational exposure group (n=12), the median age was 44.8 years (IQR: 39.04-48.35), and there was a marked predominance of males (83.3%) with significant differences compared to the non-occupational group (p=0.04).

The professions most involved included agriculture/livestock/forestry (33.3%), services (25%), and maintenance/construction (16.7%).

The most frequent clinical manifestations were cutaneous (58.3%) and cardiovascular (58.3%). Regarding severity, 65.7% of patients suffered a severe reaction (Mueller grades 3 and 4). Of these, four patients (33.3%) had mastocytosis.

Regarding diagnosis, Table 1 shows the IgE and tryptase values. After the study, 9 patients (75%) were diagnosed with sensitization to Polistes dominula, 1 (8.3%) to Vespula spp., and 1 (8.3%) to Apis mellifera. The remaining patient did not complete the diagnosis, but the causative insect was a wasp. Venom Immunotherapy (VIT) was initiated in 10 patients (83.3%), 9 with a Polistes extract and 1 with Vespula. An IT dropout rate of 30% was recorded. After starting immunotherapy, 5 patients suffered spontaneous stings and 3 patients underwent sting challenge test, with tolerance in all cases.

Our study shows that wasps can cause occupational allergies and that beekeepers are not the only ones affected by this problem. Venom immunotherapy is essential for the management of these patients. The high prevalence of mastocytosis in our group entails an additional risk to occupational exposure. It is important to contact the appropriate occupational health supervisors to report this problem.