- D1.516 - Compliance with hymenoptera venom inmunotherapy (VIT)

Hymenoptera venom immunotherapy (VIT) is a highly effective treatment for preventing future systemic reactions in patients allergic to hymenoptera venom. However, therapeutic compliance is not always optimal, which can pose a risk to patients.

A retrospective descriptive study was conducted of patients allergic to hymenoptera venom who attended the HUFA Allergy Unit between 2021 and 2025. Patients who, despite having an indication, did not start immunotherapy or did not complete treatment were included. Demographic, clinical, diagnostic, and VIT treatment data were analyzed in this group of patients.

A total of 76 patients were recruited. Of these, 19 (25%) showed poor compliance with VIT: 57.9% abandoned VIT, and 42.1% did not start it. 

The median age of patients with poor compliance (n=19) was 50.56 years (IQR: 33.16-55.20). In terms of gender, 52.6% were men. Most were at high risk of exposure (84.2%). Regarding occupation,  62.5% of patients were actively employed, mainly in the service sector (25.0%), while 18.8% were students and 18.8% were retired. 

In terms of the reaction to the sting, the most frequent clinical manifestations were cutaneous (57.9%) and respiratory (52.6%), 84.2% experienced a severe reaction (Mueller grades 3-4) and 4 patients (22.2%) were diagnosed with mastocytosis. 

Table 1 shows the specific IgE levels. The final diagnosis was allergy to Polistes dominula (63.2%), Vespula spp (10.5%), Vespula and Polistes (10.5%), and Apis mellifera (10.5%). 

The median duration of VIT in the group that discontinued treatment was 620 days (IQR: 267-959).  

No significant differences were found between patients with poor compliance and those who complied with treatment in variables such as age, sex, work activity, severity of reaction, or causative insect.

The percentage of patients who do not comply with venom immunotherapy is high. In this study, it was not possible to establish a demographic or clinical profile of non-compliant patients. It is essential to closely monitor patients undergoing VIT treatment to prevent dropouts and ensure adequate protection.