Published in: Equine Veterinary Journal, volume 48, Issue 1, January 2016
A commercially available immunoglobulin E-based test for food allergy gives inconsistent results in healthy ponies
Summary
Reasons for performing study
Commercial immunoglobulin E (IgE)-based tests are available for diagnosis of food allergies and are commonly used in equine practice. However, these tests have been proven unreliable as a screening method in man and other species, but not critically evaluated in equids. Therefore, a commercially available IgE-based test for horses was evaluated.
Objectives
To evaluate the consistency of the results obtained with a commercially available IgE-based test for food allergy diagnosis in ponies (Phase I) and to subject ponies to a provocation trial with the presumed allergens (Phase II).
Study design
Allergen screening followed by experimental food provocation trials in healthy ponies.
Methods
Blood samples of 17 healthy Shetland ponies were taken at 2 different time points, sent blinded to a commercial laboratory for screening of common food allergens and the results were evaluated for consistency (Phase I). Ponies that were positive for food allergens were consecutively challenged orally with each allergen separately for 14 days (Phase II). A washout period of one week was applied in ponies with multiple positive results. Clinical parameters and serum amyloid A were monitored during the provocation trial.
Results
Only 7/17 ponies were negative on the IgE-based test at the 2 time points, 3 had positive results twice but only one tested positive twice for the same food allergen. No abnormalities were noted during the provocation trials.
Conclusions
This study demonstrated that this IgE-based test is not a reliable screening tool for food allergy in healthy equids.
Authors: S. Dupont, A. De Spiegeleer, D. J. X. Liu, L. Lefère, D. A. van Doorn, M. Hesta
