title: Cross-reaction and co-sensitization among related and unrelated allergens in canine intradermal tests.
abstract: BACKGROUND
  Intradermal tests are used to identify allergens for avoidance and immunotherapy in atopic dogs.
  
  
  OBJECTIVE
  To evaluate cross-reaction or co-sensitization among 53 intradermal test allergens.
  
  
  METHODS
  Six hundred and fifty-one client-owned dogs with atopic dermatitis.
  
  
  METHODS
  Intradermal tests were performed with 53 house dust/storage mite, epidermal, insect, tree, weed and grass pollen and mould allergens. Pairwise comparisons were used to calculate the odds ratios (ORs), 95% confidence intervals (CIs) and statistical significance for the results of each allergen pair, with significance at P < 0.0006 (Holm-Bonferroni correction to reduce the false-detection rate).
  
  
  RESULTS
  Apart from cotton, cockroach, red clover, grain smut and Penicillium, the results for the allergens within each group were statistically associated [ORs from 4.7 (CI 2.5-8.9) to 1229.4 (CI 166.5-1795.1); P = 0.0005 to P < 0.0001]. Excluding red clover and cotton, 94% of results between tree, weed and grass pollens were also statistically associated [ORs from 8.3 (CI 3.6-24.7) to 117 (CI 29.1-341); P = 0.0005 to P < 0.0001]. In contrast, few allergens from unrelated groups were statistically associated [ORs from 0.12 (CI 0.03-1.1) to 27.7 (CI 0.2-93); P = 1.0 to P < 0.0001]. The mean (SD) of the log e transformed ORs for the related and statistically associated allergens [5.3 (1.3)] was significantly greater than those for related but nonstatistically associated [1.7 (1.6)] or unrelated allergens [1.4 (1.4); P < 0.0001].
  
  
  CONCLUSIONS
  This suggests that there is cross-reaction or co-sensitization between related allergens. This could have implications for allergen selection in testing and immunotherapy, but further studies are required to differentiate cross-reaction from co-sensitization.
authors.affiliation: The University of Liverpool School of Veterinary Science, Leahurst Campus, Chester High Road, Neston, Cheshire, CH64 7TE, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Buckley
authors.forename: Vanessa
authors.initials: V
authors.lastname: Schmidt
authors.forename: Neil
authors.initials: N
authors.lastname: McEwan
authors.forename: Tim
authors.initials: T
authors.lastname: Nuttall
mesh_terms: D000485:Allergens; D000818:Animals; D004283:Dog Diseases / Q000276:immunology*; D004285:Dogs; D006967:Hypersensitivity / Q000175:diagnosis / Q000662:veterinary*; D007271:Injections, Intradermal; D007313:Insecta; D008925:Mites; D016017:Odds Ratio; D011058:Pollen / Q000145:classification; D012882:Skin Tests / Q000662:veterinary*
chemical_list: D000485:Allergens