Objective: The purpose of this study was to evaluate concurrent positive reactions of related versus nonrelated allergens based on 1000 intradermal tests of dogs with atopic dermatitis.
Procedure: Pairs of closely related allergens (based on botanical relations and results of research in human allergic disease) and nonrelated allergens were evaluated. Significance of the difference between group means of log odds ratios was estimated using a Bootstrap percentile confidence interval.
Results: There was a significant difference in the mean log odds ratio between related and nonrelated allergen pairs. However, there was also a significant difference between most groups consisting of nonrelated allergen pairs.
Conclusion: These results provide conflicting evidence and emphasise the need for further studies. Numbers of concurrent reactions of related allergens indicate that immunotherapy should be formulated based on testing with single allergens to avoid exposure to allergens not involved in the dog's atopic disease.