Effect of a novel topical diester glucocorticoid spray on immediate- and late-phase cutaneous allergic reactions in Maltese-beagle atopic dogs: a placebo-controlled study

Abstract

The inhibitory effect of 0.0584% hydrocortisone aceponate spray on immediate- and late-phase skin reactions and the duration of inhibition after medication withdrawal were studied in 10 Maltese-beagle atopic dogs. All subjects were sprayed on axillary and inguinal regions and on one randomly chosen side of the thorax once daily for 14 (phase 1) or 7 days (phase 2). Intradermal injections (IDT) of histamine and anticanine IgE antiserum were performed bilaterally on the thorax before, 7 and 14 days after treatment. During phase 2, IDT was performed once weekly for 5 weeks. Each IDT was evaluated by an investigator blinded to the site of active treatment. Skin biopsies of 24-h anti-IgE-associated late-phase reactions were collected from both thoracic sides before and 14 days after treatment to determine the number of inflammatory cells and dermal thickness. Phase 1: Histamine and anti-IgE-induced global wheal scores at treated sites were significantly lower after 7 and 14 days with negative reactions present in >90% of dogs. Late-phase reactions at both sides were also significantly decreased compared with that at baseline, and this was associated with reduced inflammatory cell influx. Moreover, a significant decrease in dermal thickness was recorded at treated sides after 14 days. Phase 2: Histamine reactions became positive at untreated sides in all dogs 2 weeks after treatment. In conclusion, the 0.0584% hydrocortisone aceponate spray significantly decreased immediate- and late-phase IDT reactions, and prolonged application caused skin atrophy at treated sites. A 2-week withdrawal period prior to IDT is proposed.

Inhibitory effect of topical Adelmidrol on antigen-induced skin wheal and mast cell behavior in a canine model of allergic dermatitis

“…Indeed, similar findings emerged from a study on a model of chronic inflammation, where the local administration of adelmidrol both down-modulated MC degranulation and prevented numerical increase of MC numbers [20]. Interestingly, topical corticosteroids decrease MC numbers in humans [56], without any apparent effect on dogs [44]. …”

“…The key findings are summarized in Table 2. The effect of corticosteroids (both oral or topical) on intradermally-induced skin wheal ranges from lack of effect [38,39] up to 45% inhibition [40-43], with the only exception of one single study (72% inhibition rate) [44]. Interestingly, similar results are observed in allergic human patients (i.e., 30-40% inhibition) [45], and better outcomes are known to occur with longer treatment [46].…”

Evidence‐based guidelines for anti‐allergic drug withdrawal times before allergen‐specific intradermal and IgE serological tests in dogs

“…injections were significantly reduced on both treated and untreated sides of the thorax after 7 and 14 days. Normal to near normal immediate reactivity to histamine returned at untreated sites within 2 weeks of discontinuation of treatment …”

“…In summary, the variability of the study designs and products used renders the determination of universal OWT and MWT difficult. Nevertheless, based on the evidence available from the testing of a potent topical glucocorticoid (Cortavance; Virbac, Carros, France), an OWT of 14 days is proposed (Table ). For lower‐potency topical glucocorticoid formulations, an MWT of 0 days is likely to be possible …”

Pilot Study to Evaluate the Effect of Topical Dimethicone on Clinical Signs and Skin Barrier Function in Dogs with Naturally Occurring Atopic Dermatitis

“…Dogs were off all oral antihistamines, cyclosporine for a minimum of 1 month, essential fatty acid supplements, and long-acting injectable glucocorticoids for a minimum of 2 months while oral [26] and topical glucocorticoids for a variable time (5–14 days) [27]. The withdrawal time took into consideration also the type of glucocorticoids prescribed and the duration of treatment, as it would be done in clinical practice before intradermal skin testing.…”