Sensitization to environmental allergens by skin test in dogs with atopic dermatitis in Ourinhos/SP, Brazil, and region1

Abstract

ABSTRACT: Canine atopic dermatitis (CAD) is a hereditary and multifactorial disease caused by an immediate hypersensitivity response to one or more allergens, leading to a specific and chronic immune response. Pruritus and inflammatory conditions are frequently observed, ranging from moderate to severe. Clinically relevant allergens include house dust mites and grass pollens. Currently, the skin prick test is used as a method to identify immune-specific allergic reactions mediated by immunoglobulin E. Therefore, the present study aimed to identify the incidence of sensitization to environmental allergens by skin prick test in 200 dogs with atopic dermatitis in Ourinhos (SP, Brazil) and the region. The study had a retrospective character and analyzed data collected from 2022 to 2024, selecting atopic dogs that lived exclusively indoors and underwent the skin prick test. Of these, 53% (106/200) were sensitized for Dermatophagoides farinae (Df), 53.50% (107/200) for Dermatophagoides pteronyssinus (Dp), 54% (108/200) for Blomia tropicalis (Bt), 31.50% (63/200) for Cynodon dactylon (Cd), 26.50% (53/200) for Lolium perenne (Lp), and 27.50% (55/200) for Paspalum notatum (Pn). Regarding mosquitoes (Culex sp. and Aedes aegypti), 45% (90/200) showed sensitization, and 55% (110/200) showed absence of sensitization. The results demonstrated a higher frequency of sensitization to house dust mites, suggesting relevance in the sensitization profile of dogs in this region. However, these findings reflect sensitization and do not indicate a clinically relevant allergic condition. Environmental control measures to reduce exposure to house dust mites may be considered in clinical management, although further studies are required to determine the impact on disease expression.