Natural History of the Hymenoptera Venom Sensitivity Reactions in Adults: Study Design.

BACKGROUND: Allergic reactions to Hymenoptera stings can have varying levels of severity, according to the Müller grading system. METHODS: By an epidemiological concept, this is a retrospective cohort study. The observed cohort was represented by patients referred to the University Clinic Golnik due to Hymenoptera allergic reaction in the period from 1997 to 2015. From the immunological database of the University Clinic Golnik, we obtained laboratory data (sIgE, skin tests and basophil activation test). The clinical characteristics of patients were obtained from BIRPIS. With the help of a questionnaire, which was sent to each patient in the period from May 2019 to April 2021, we obtained epidemiological data. For the assessment of the association between the severity of allergic reaction for the observed outcome, the severity of the first allergic reaction after Hymenoptera sting was used. Other variables were grouped according to risk factors. DISCUSSION: We will identify the risk factors that could play an important role in a severe systemic reaction: the aetiology of the Hymenoptera sting, sex, age, history and severity of previous systemic reactions, being re-stung in an interval of two months, the frequency of re-stings, atopy, genetic predisposition, preventive medication use, other medication use, beekeeping or living next to beehives and why immunotherapy was not taken. Laboratory data will also be analysed to determine if there is any association with laboratory tests and the severity of the allergic reactions after Hymenoptera stings. CONCLUSIONS: Several new approaches are introduced in the study design. The most important is that the protocol covers epidemiological data gained from the questionnaire, as well as clinical data gained from the Immunological database and BIRPIS database. We expect to obtain significant results that will explain the risk factors for the natural history of Hymenoptera sting allergic reactions and will help allergologists, as well as general doctors, when facing those patients allergic to Hymenoptera venom without immunotherapy.