Hymenoptera Venom Immunotherapy in Dogs: Safety and Clinical Efficacy

SIMPLE SUMMARY: Insect venom allergy is a potentially life-threatening allergic reaction following a bee, wasp, or ant sting. The only treatment to prevent further systemic sting reactions is venom immunotherapy (VIT), with an efficacy of up to 98% in humans. Prospective clinical data on VIT efficacy in dogs are currently lacking. In this investigation, 10 dogs with severe allergic reactions to either bee or wasp stings were treated with VIT. All dogs tolerated the therapy without adverse effects and the dogs which were re-stung tolerated the sting. This means that VIT is not only safe, but also efficacious in these patients. Furthermore, it was also shown that in addition to skin testing, two serum allergen-specific IgE tests were reliable to identify the underlying patients’ insect sensitization pattern. ABSTRACT: Hymenoptera allergens are the main triggers for anaphylaxis in susceptible dogs and humans. Hymenoptera venom specific immunotherapy (VIT), the only disease-modifying treatment, has the potential to prevent future life-threatening reactions in human patients. Prospective clinical data on VIT efficacy in dogs are currently lacking. Therefore, the aim of this study was to show that VIT is not only safe but also efficacious in preventing anaphylaxis in dogs allergic to Hymenoptera. This uncontrolled prospective clinical trial included 10 client-owned dogs with a history of anaphylaxis following repeated Hymenoptera stings. The sensitization to bee and wasp allergens was demonstrated by intradermal testing (IDT) and allergen-specific IgE serology. For VIT induction (induction phase), dogs received a shortened rush immunotherapy protocol with aqueous allergens, which was then followed by monthly injections of 100 µg of alum-precipitated allergen (maintenance phase). VIT efficacy was determined by observing patients’ clinical reactions to re-stings. No systemic adverse events were seen during the induction and maintenance phases. From the seven re-stung dogs, only one developed a mild angioedema at the site of the sting; the remaining dogs were asymptomatic. These results show that VIT represents a safe and effective treatment option for Hymenoptera-allergic dogs.