Intra- and interlaboratory variability of allergen-specific IgE levels in atopic dogs in three different laboratories using the Fc-ɛ receptor testing

Abstract

The IgE specific Fc-epsilon receptor test is widely used for serological evaluation of allergic canine patients. Aim of the study was to evaluate intra- and interlaboratory variability in three independent laboratories. Duplicate serum aliquots from 15 atopic dogs were submitted simultaneously to 3 laboratories (LA, LB, LC), which subsequently performed the test in a blinded fashion. LA and LC analysed sera for 35 allergens and expressed the results as optical density units (OD), while LB analysed 15 allergens and provided reaction grades (RG). Results were compared with three factorial ANOVA. Intralaboratory variability was evaluated by calculating the dispersion factor for data of LA and LC and standard deviation (SD) for LB. Correlation coefficients (r) were used to evaluate interlaboratory variability. Depending on the allergens, intralaboratory dispersion factor for LA and LC varied from 1.15 to 6.63 and 1.19 to 6.17, respectively. In LB the SD varied between 0 and 0.6 RG. Regarding interlaboratory variability, correlation of OD values between LA and LC was excellent (r>0.8, p<0.001) for 13 of 35 allergens. There was a significant difference in OD results for 9 allergens. The results were significantly correlated (r>0.8, p<0.001) for all except 3 allergens (Dermatophagoides pteronyssinus, mixed grasses, nettle). As far as negative/positive results were concerned, intralaboratory differences were 3.14% and interlaboratory differences were 4.76%.

Food‐specific serumIgEandIgGreactivity in dogs with and without skin disease: lack of correlation between laboratories

“…A recent report described similar variability between four veterinary laboratories offering allergen‐specific IgE assays for environmental allergens, and poor intralaboratory reproducibility has also been reported . The results of the present study support previous urgent calls for standardization and the application of independent systematic quality control approaches to veterinary laboratories offering tests of this nature …”

“…63 The results of the present study support previous urgent calls for standardization and the application of independent systematic quality control approaches to veterinary laboratories offering tests of this nature. [63][64][65] different laboratories using the Fc-e receptor testing. Vet Immunol Immunopathol 2009; 133: 183-189.…”

Review: The role of antibodies, autoantigens and food allergens in canine atopic dermatitis

“…While the results obtained from such different assays often correlate reasonably well, this is not always the case . For that matter, some differences can be identified even between laboratories using the same methodology or even within the same laboratory . Currently, there are no standardized guidelines or regulations for the accreditation of veterinary allergy laboratories, or for the development of quality assurance programmes for those laboratories.…”

Effectiveness of regionally-specific immunotherapy for the management of canine atopic dermatitis

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