title: Intradermal and serological testing for mites in healthy beagle dogs.
abstract: BACKGROUND
  Intradermal testing (IDT) is widely used in veterinary medicine to select allergens for immunotherapy. The recommended concentration for mites is 250 protein nitrogen units (PNU)/mL. It is not known whether healthy dogs responding to this concentration have asymptomatic sensitization or irritation. Furthermore, interbatch and intersupplier variability of allergens has not been fully addressed.
  
  
  OBJECTIVE
  The incidence of positive IDTs in healthy beagles was recorded and the value of combining these results with serology to differentiate between asymptomatic sensitization and irritancy evaluated. Additionally, the interbatch and intersupplier variability of allergens was assessed.
  
  
  METHODS
  Seventeen healthy laboratory beagles with no history or clinical signs of canine atopic dermatitis were used.
  
  
  METHODS
  Intradermal tests were performed with four mite allergens from two suppliers (varying batches). An initial IDT at 250 PNU/mL was used to determine whether decreasing or increasing test concentrations were used in the subsequent titration IDTs. Additionally, two IgE ELISA tests from different manufacturers were performed.
  
  
  RESULTS
  Seven of 17 dogs showed IDT reactions at 250 PNU/mL. There were highly significant allergen interbatch and significant intersupplier correlations and agreement. The associations between the IDT reactions and the IgE serologies statistically identified two groups of dogs: one with positive serology and IDT reactions at 250 PNU/mL; and another with negative serology and IDT reactions.
  
  
  CONCLUSIONS
  Our results suggest that dogs that have IDT reactions and positive serology are asymptomatically sensitized, while dogs that react at higher allergen concentrations, but have negative serology, do so as a result of irritant reactions.
authors.affiliation: Kleintierpraxis Dr Koebrich and Partner, Neulussheim, Germany. steffi@dr-koebrich.de
authors.forename: Stefanie
authors.initials: S
authors.lastname: Koebrich
authors.forename: Claudia
authors.initials: C
authors.lastname: Nett-Mettler
authors.forename: Sylvia
authors.initials: S
authors.lastname: Wilhelm
authors.forename: Claude
authors.initials: C
authors.lastname: Favrot
mesh_terms: D000485:Allergens / Q000276:immunology; D000818:Animals; D003876:Dermatitis, Atopic / Q000175:diagnosis / Q000469:parasitology / Q000662:veterinary; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis / Q000469:parasitology*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D007428:Intradermal Tests / Q000379:methods / Q000662:veterinary*; D008297:Male; D008924:Mite Infestations / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D008925:Mites / Q000276:immunology; D039981:Pyroglyphidae / Q000276:immunology
chemical_list: D000485:Allergens