Abstracts: This study was carried out to identify which allergens are found more frequently in dogs with atopic dermatitis in Mexico City. 250 cases, in which intradermal skin testing was performed, were reviewed. 175 dogs (70%) had positive reactions. The most important allergens were American cockroach (Periplaneta americana) (51.72%), Dermatophagoides pteronyssinus (51.72%) and Dermatophagoides farinae (41.37%).
Atopic dermatitis is a chronic inflammatory skin disease caused by environmental antigens that in nonatopic animal create no disease. It has been considered that atopy may affect around 10% of the canine population. Hyposensitization is the mainstay of therapy in canine atopic dermatitis and intradermal skin testing is preformed to select the allergens to be used.
There are several studies about the frequency of allergens in dogs and humans, but the frequency varies among authors, this is because there is a wide variability in vegetation and climatic conditions.
There are not studies in Mexico that determine which allergens are important in dogs with atopic dermatitis. Even though, there are studies in Mexico in human medicine, it has been seen that allergens of importance in atopic humans may not be an accurate reflection of allergens of importance in dogs.
Identify which allergens are found more frequently in dogs with atopic dermatitis in Mexico City.
Material and Methods
The cases of atopic dogs, in which intradermal skin testing was performed, were reviewed and the frequency of positive reactions to each allergen was determined. 71 allergens were tested in each dog (19 grass pollens, 18 tree pollens, 12 weed pollens, 16 molds, 3 insects, 2 dust mite and house dust).
Results
Intradermal skin testing was performed in 250 cases, 175 cases (70%) had positive reactions.
As a group, grass pollens were responsible of 24.59% of positive reactions, weed pollens of 18.18%, tree pollens of 17.64%, insects and dust mite of 14.43%, molds of 8.55% and house dust of 2.14%.
As individual allergens, American cockroach (Periplaneta americana) y Dermatophagoides pteronyssinus caused positive reactions in 51.72% of the cases, German cockroach (Blatella germanica) and Australian pine (Casuarina equisetifolia) 24.13%, castorbean (Ricinus communis), sorghum (Sorghum vulgare) and smooth pigweed (Amaranthus hybridus) 20.68%, ant (Formica sp), carless weed (Amaranthus palmeri), (Bromus carinatus) y Hungarian brome (Bromus inermis) 17.24%, orchard grass (Dactylis glomerata), side oats grama (Bouteloua sp), field mustard (Brassica campestris) y house dust 13.79%, perennial ragweed (Ambrosia psilostachya), pigweed rough (Amaranthus retroflexus), rye grass (Festuca elatior), Kentuky bluegrass (Proa pratensis), (Secale cereale), white ash (Fraxinus americana), black willow (Salix nigra), hickory (Carya sp), Rhizopus, Puccina y Pullularia en el 10.34%.
31 allergens were positive in less than 10% of the cases and 13 allergens were negative.
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