Canine atopic dermatitis (CAD) is a multifaceted disease associated with exposure to various offending agents such as environmental and food allergens. The diagnosis of this condition is difficult because none of the typical signs are pathognomonic. Sets of criteria have been proposed but are mainly used to include dogs in clinical studies. The goals of the present study were to characterize the clinical features and signs of a large population of dogs with CAD, to identify which of these characteristics could be different in food-induced atopic dermatitis (FIAD) and non-food-induced atopic dermatitis (NFIAD) and to develop criteria for the diagnosis of this condition. Using simulated annealing, selected criteria were tested on a large and geographically widespread population of pruritic dogs. The study first described the signalment, history and clinical features of a large population of CAD dogs, compared FIAD and NFIAD dogs and confirmed that both conditions are clinically indistinguishable. Correlations of numerous clinical features with the diagnosis of CAD are subsequently calculated, and two sets of criteria associated with sensitivity and specificity ranging from 80% to 85% and from 79% to 85%, respectively, are proposed. It is finally demonstrated that these new sets of criteria provide better sensitivity and specificity, when compared to Willemse and Prélaud criteria. These criteria can be applied to both FIAD and NFIAD dogs.

The objective of this multicentre, parallel, blinded, randomized controlled study was to evaluate the efficacy and the safety of cyclosporine (CsA group, 117 dogs) in comparison with methylprednisolone (MP group, 59 dogs) in the treatment of atopic dermatitis for 4 months. Mean induction dose of both drugs (5 mg/kg CsA, 0.75 mg/kg MP) was tapered over time according to the clinical response. At the end of the study, the mean estimated percentage reduction from baseline (confidence interval) of lesion scores was 52% (44-59) and 45% (35-56), and the reduction in pruritus score was 36% (27-43) and 33% (23-43) in dogs in the CsA and MP groups, respectively. These percentages were not significantly different between groups. A significantly better overall assessment of efficacy was obtained in the CsA-treated dogs (76 vs. 63% responses excellent or good in the CsA compared with MP group). CsA-treated dogs presented a higher frequency of gastrointestinal disorders, mainly vomiting, but MP dogs tended to be more susceptible to infections. There was no remarkable change over baseline of the haematological and biochemical parameters in the two groups.

Results suggest that oral administration of cyclosporine at a dosage of 5.0 mg/kg once daily is effective in reducing severity of pruritus and skin lesions in dogs with AD, especially those with nonseasonal disease.

Results suggest that cyclosporine is efficacious for the treatment of atopic dermatitis in dogs and that frequency of cyclosporine administration can be reduced following an initial induction period. The drug was well tolerated.

The efficacy of cyclosporin A (CsA) for the treatment of canine atopic dermatitis was evaluated based on the systematic review of prospective clinical trials published between 2001 and 2005. Ten studies with adequate design characteristics were included. These studies enrolled 799 dogs, 672 (84%) treated with CsA, 160 (20%) with placebo, 74 (9%) with oral glucocorticoids and 23 (3%) with antihistamines. Treatment duration varied from 2 weeks to 6 months. For safety analysis, data were available from 660 dogs. Lesion scores were improved from baseline in the range of 30-52%, 53-84% and 52-69% after 4, 6 and 16 weeks, respectively. The percentage of dogs with only mild pruritus rose from 0-13% at inclusion to 32-59% and 46-90% after 4 and 12 weeks, respectively. In most studies, the frequency of CsA administration could be reduced to every other day in 40% to 50% of patients after 4 weeks and to twice weekly in 20-26% of the dogs after 12-16 weeks. Meta-analysis confirmed highly significant effects of CsA compared to placebo, but none between oral CsA and glucocorticoids. The initial disease severity, age or body weight of subjects did not influence treatment success. Improvement by more than 50% over baseline of lesion scores was predictive of a better response during treatment maintenance. Vomiting and soft stools/diarrhoea were the most frequent adverse events seen at least once during the studies. These occurred in 25% and 15% of subjects, respectively. The frequency of each other type of adverse events was lower than 2.1%. In summary, the administration of CsA for the treatment of canine AD was found to be as effective as that of glucocorticoids, and adverse effects were minimal.