Efficacy of subcutaneous allergen immunotherapy in atopic dogs: A retrospective study of 664 cases

Background Canine atopic dermatitis (cAD) is an allergic skin disease affecting approximately 10% of dogs. allergen‐specific immunotherapy (ASIT) is currently the only treatment option able to induce tolerance to the causative allergens. Objective To retrospectively establish the efficacy of ASIT in atopic dogs. Animals Client‐owned (n = 664) dogs with cAD presented between 2008 and 2018 to two dermatology referral clinics. Materials and Methods Clinical records of atopic dogs were reviewed to obtain information including the results of the intradermal skin test and/or allergen‐specific immunoglobulin (Ig)E serological results, the allergens included in the ASIT, concurrent symptomatic medications, and ASIT efficacy after at least 9 months. Results Excellent (ASIT alone controlled clinical signs), good (≥50% reduction of clinical signs) and poor (50% improvement in 69.3% and 55.4% of the dogs, respectively). Dogs treated with ASIT and concomitant systemic glucocorticoids showed a significantly poorer response (success rate of >50% improvement of 38.5%). Conclusions and clinical importance In 59.9% of atopic dogs, subcutaneous ASIT can improve clinical signs by ≥50%. The beneficial effect of ASIT is higher if dogs are re‐examined regularly and if systemic long‐term corticosteroids are avoided, at least during the first 9 months of ASIT. Résumé Contexte – La dermatite atopique canine (DAC) est une maladie cutanée allergique qui touche environ 10 % des chiens. L'immunothérapie allergénique (ASIT) est actuellement la seule option thérapeutique capable d'induire une tolérance aux allergènes responsables. Objectif – Établir rétrospectivement l'efficacité de l'ASIT chez les chiens atopiques. Animaux – Chiens de clients (n = 664) atteints de DAC présentés entre 2008 et 2018 à deux cliniques de référé en dermatologie. Méthodes ‐ Les dossiers cliniques des chiens atopiques ont été examinés pour obtenir des informations, notamment les résultats du test cutané intradermique et / ou les résultats sérologiques de l'immunoglobuline (Ig) E spécifique d’allergène, les allergènes inclus dans l'ASIT, les médicaments symptomatiques concomitants et l'ef