Hymenoptera Venom Immunotherapy in Dogs: Safety and Clinical Efficacy

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.

Keywords: Hymenoptera allergy; anaphylaxis; angioedema; dogs; urticaria; venom immunotherapy.

Figure 1

Skin testing procedure. The sequence and allergen concentrations for the skin testing (a), skin prick testing procedure (b), and intradermal testing procedure (c). All allergens were injected simultaneously.

Figure 2

Presentation of the in-clinic challenge with a bee. Patients are closely monitored during in-clinic challenge (a), the insect is gently grabbed by forceps and brought to the skin in the inguinal area (b,c). In case of bee stings, their stinger is removed after a few minutes. At the stung area, a well-defined erythematous wheal (arrow) should appear (d). If no reaction is observed, the procedure is repeated with a new insect. Finally, the remaining insects are transported back and freed into their natural environment (e).

Figure 3

The correlation between PAX^® and Allercept^®-derived bee-specific IgE levels by Pearson’s correlation coefficient.