Results of intradermal tests in horses without atopy and horses with atopic dermatitis or recurrent urticaria.
OBJECTIVE
To compare results of intradermal tests (IDT) for environmental allergens at 30 minutes and 4, 6, and 24 hours after injection in horses without atopy and horses with atopic dermatitis (AD) or recurrent urticaria (RU).


METHODS
22 horses without atopy, 10 horses with RU, and 7 horses with AD.


METHODS
In all horses, medical history was obtained, and results of physical examination, hematologic examination, serum biochemical analyses, examination of bronchoalveolar lavage fluid, and IDT with 73 allergens were examined.


RESULTS
Horses with AD or RU had a significantly greater mean number of positive reactions for IDT, compared with horses without atopy. Horses with AD had a significantly greater number of positive reactions than horses without atopy in every allergen group at all time periods, except for molds at 4 and 24 hours. Horses with RU had a significantly greater number of positive reactions than horses without atopy in every allergen group, except for molds at 30 minutes and 4 and 6 hours, trees at 4 and 6 hours, and grasses at 4 hours.


CONCLUSIONS
A significantly greater number of positive reactions for IDT in horses with AD or RU, compared with horses without atopy, provides evidence of type-I IgE-mediated hypersensitivity for these diseases. Evaluation of results of IDT performed in horses with AD or RU is useful in determining specific allergens for the formulation of immunotherapy along with providing identification of allergens that could be useful when creating avoidance strategies.
Lorch
G
G
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus 43210-1089, USA.
Hillier
A
A
Kwochka
K W
KW
Saville
W A
WA
LeRoy
B E
BE
D000485:Allergens / Q000276:immunology; D000818:Animals; D001314:Auscultation / Q000662:veterinary; D001772:Blood Cell Count / Q000662:veterinary; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D003876:Dermatitis, Atopic / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D005260:Female; D005658:Fungi / Q000276:immunology; D006651:Histocytochemistry / Q000662:veterinary; D006734:Horse Diseases / Q000276:immunology* / Q000473:pathology; D006736:Horses; D007313:Insecta / Q000276:immunology; D008168:Lung / Q000473:pathology; D008297:Male; D006109:Poaceae / Q000276:immunology; D012882:Skin Tests / Q000662:veterinary*; D014197:Trees / Q000276:immunology; D014581:Urticaria / Q000276:immunology / Q000473:pathology / Q000662:veterinary*
D000485:Allergens