Benefits of venom immunotherapy: How soon can they be expected

Introduction/Objective. Allergic reactions to insect stings are medical emergencies that could be prevented by venom immunotherapy (VIT). The main purpose of VIT is to prevent fatal or life-threatening reactions. We aimed to show the rapidity with which patients experience the benefits of VIT and estimate the number of emergency treatments that are prevented. Methods. We reviewed the medical files of patients who started VIT between 2010 and 2014. We calculated the costs of treatment of the sting reactions, the costs of immunotherapy, and estimated the costs of prevented allergic reactions. Results. In a cohort of 514 patients (40.9% female, age 47.2 ? 14.4 years), the cost of treatment of the index sting reaction was 180.4 ? 166.8 euros. During VIT, 195 patients experienced 446 field stings. In 86.3% of patients, stings were well tolerated, and only one patient experienced a severe reaction (grade III, according to Mueller). A total of 20.4% of VIT treated patients were stung during the first year of VIT and 57% during five years of VIT. The expenditure for five years of VIT was 2,886 euros per patient, which corresponded to an average of 16 emergency treatments for systemic reactions. Conclusion. Emergency situations are prevented in a substantial number of venom-allergic patients and a beneficial effect was already observed during the first year of VIT.