Serum IgE against cross-reactive carbohydrate determinants (CCD) in healthy and atopic dogs.

Background: Cross-reactive carbohydrate determinants (CCD) are Immunoglobulin E (IgE)-binding carbohydrate structures common to plant and insect species. In people, anti-CCD IgE is thought to be clinically irrelevant, but to have the potential to confound serological IgE test interpretations. Previous studies reported the detection of anti-CCD IgE in 24-73% of atopic dog sera; prevalence in healthy dogs has not been reported.

Objective: To compare the prevalence of anti-CCD IgE in a group of healthy and atopic dogs.

Animals: Sera from 61 healthy dogs and 101 dogs with a clinical diagnosis of atopic dermatitis were analyzed for IgE against CCD.

Methods And Materials: Sera were analyzed for the presence of anti-CCD IgE and IgE against environmental allergens using a commercial multiplex allergen-specific IgE assay.

Results: Anti-CCD IgE was detected in 17 of 101 (16.8%) atopic dog sera and eight of 61 (13.1%) healthy dog sera (P = 0.65, Fisher's exact test). All healthy and atopic dogs with anti-CCD IgE had strong reactivity to grass pollens.

Conclusions And Clinical Importance: A similar prevalence of anti-CCD IgE was found in healthy and atopic dogs. Further investigation is warranted to determine the clinical significance of anti-CCD IgE antibodies in dogs, how they are best detected and if blocking these antibodies during diagnostic testing has clinical value.