Investigation of antinuclear antibodies in canine atopic dermatitis.
Serum samples from 40 atopic dogs and 20 healthy dogs were assayed for antinuclear antibodies (ANA) using a human epithelial cell line (HEp-2) and standard indirect immunofluorescent methods. Samples from the atopic dogs were grouped according to the presence (n = 28) or absence (n = 12) of facial lesions at any moment during the follow-up period. Positive ANA titres were found in 10 of the 40 atopic dogs analysed (25%) whereas samples from the control group were negative. Eight atopic dogs with facial lesions had a positive titre (28.57%) in contrast with atopic dogs without facial lesions where two positive samples (16.67%) were found; however, the differences were statistically not significant. Endpoint titres were low (1/40), only two samples yielded a 1/80 positive titre and one sample had a 1/320 titre, all of them from the facial lesions group. Response to immunotherapy was classified as positive only in four of the 10 ANA-positive patients (40%) compared with a response rate of 73% (22 of 30) in the ANA-negative atopic dogs. However, a Fisher's exact test showed a two-sided P-value of 0.122 which was considered statistically not significant. The overall response rate to immunotherapy for all atopic dogs was 65% (26 of 40). In conclusion, the prevalence of ANA is higher in atopic than in healthy dogs, especially if facial lesions are present. Although a clinically significant pathogenic contribution is not probable, this higher prevalence should be taken into account in the differential diagnosis of canine autoimmune dermatitis.
Ginel
P J
PJ
Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Córdoba, Córboda, Spain. pvlgipep@uco.es
Lucena
R
R
D000818:Animals; D000974:Antibodies, Antinuclear / Q000097:blood*; D016022:Case-Control Studies; D003876:Dermatitis, Atopic / Q000276:immunology / Q000662:veterinary*; D004283:Dog Diseases / Q000097:blood / Q000276:immunology* / Q000628:therapy; D004285:Dogs; D005148:Facial Dermatoses / Q000276:immunology / Q000662:veterinary; D005260:Female; D005455:Fluorescent Antibody Technique / Q000662:veterinary; D006801:Humans; D007167:Immunotherapy / Q000662:veterinary; D007428:Intradermal Tests / Q000662:veterinary; D008297:Male
D000974:Antibodies, Antinuclear