Background -Once the signs of canine atopic dermatitis (AD) are controlled, the proactive application of topical glucocorticoids can delay disease flares.Objectives -We wished to determine if the proactive administration of the anti-IL-31 lokivetmab would prevent or delay flares of canine AD.Animals -We tested this strategy in four Maltese-beagle atopic dogs before enrolling 21 dogs with spontaneous AD.Methods and materials -In our acute AD model, house dust mite (HDM)-sensitized dogs were injected once with lokivetmab. After seven days, an HDM suspension was applied epicutaneously, and both skin lesions and pruritus manifestations were quantified for 24 h. In a second study, 21 dogs with spontaneous AD controlled with anti-allergic drugs were treated with lokivetmab per manufacturer's recommendations; all anti-allergic drugs were discontinued within four weeks after the first injection. All dogs were followed prospectively for at least one year and the time-to-flare (TTF) of AD after the last day of anti-allergic treatment was determined.Results -In the experimental study, one injection of lokivetmab prevented nearly all expected allergen-induced pruritus manifestations but not skin lesion development. In dogs with spontaneous AD, the median TTF after lokivetmab proactive therapy was 63 days. One-fourth of dogs did not exhibit a flare for at least one year while receiving lokivetmab monotherapy.Conclusions -Although lokivetmab seems more effective to prevent pruritus than skin lesions in dogs with experimental AD' it also can delay disease flares in some dogs with the spontaneous disease. Studies are needed to identify those patients most likely to respond to such a proactive regimen.Abbreviations: AD, atopic dermatitis; DPM, duration of pruritus manifestations; HCA, hydrocortisone aceponate; HDM, house dust mite; mAb, monoclonal antibody; SLS, skin lesion score; TSLP, thymic stromal lymphopoietin; TTF, time-to-flare. Accepted 18 November 2018 Sources of funding: Chie Tamamoto-Mochizuki received a graduate student stipend by Zoetis. Conflict of interest: Thierry Olivry has received lecture honorarium and research funding from Zoetis.

Background -To optimise the interleukin (IL)-31-blocking therapy in atopic dermatitis (AD), an understanding of the chronology in the expression of IL-31 and its receptor (IL-31RA) is needed.Hypothesis/Objectives -(i) To assess the chronological expression of IL-31 in canine AD skin lesions, (ii) to compare it with serum IL-31 levels and macroscopic skin lesion scores, and (iii) to determine the identity of IL-31and IL-31RA-positive cells.Animals -Four atopic dogs sensitised to house dust mites.Methods and materials -Skin and blood samples were obtained 0 h, 24 h, 48 and 96 h after allergen provocation. IL-31 and IL-31RA single-staining immunofluorescence (IF), as well as IL-31/CD3, IL-31/CD4 and IL-31RA/ b3-tubulin double-staining IF were performed. The IL-31-positive cells were counted subjectively.Results -The peak IL-31 expression for three of four dogs occurred 24 h or 48 h postchallenge; it started to decrease at 96 h. There was no significant correlation between the IL-31 expression scores and the serum IL-31 concentrations or the macroscopic skin lesion scores (P = 0.35 and P = 0.36, respectively). The majority of IL-31positive cells were positive for CD3 (range 91-100%) and CD4 (range 63-100%), indicating that they were helper T (Th) cells. Unexpectedly, sebaceous glands were strongly immunolabelled with IL-31; the extinction of this positivity after immunoabsorption with IL-31 further supported the validity of this immunostaining. The IL-31RA was visualised on keratinocytes and a small proportion of dermal nerves.Conclusions and clinical importance -The early and transient production of IL-31 by Th cells supports the concept of using IL-31 inhibiting strategies as a proactive therapy to prevent flares of AD skin lesions.

To the best of the authors' knowledge, this is the first case report of ARCI with homozygous PNPLA1 mutation in a golden retriever-poodle cross-bred dog. The long-term combination of oral fatty acids and topical therapy appeared to be beneficial in this case.

Background Canine pyoderma is a common skin infection caused predominantly by staphylococcal bacteria. Because of increasing rates of antimicrobial resistance in bacterial isolates, there is an urgent need for alternative or supplementary treatment options. W16P576, a Water Extract of Complex Mix of Edible Plants (WECMEP), has shown in vitro activity against a variety of bacteria, including Staphylococcus pseudintermedius. A canine model of pyoderma was developed which allows in vivo testing of antimicrobial agents in a controlled environment. Objective To evaluate the antibacterial efficacy of topical application of W16P576 in a model of canine pyoderma. Animals Nine laboratory housed beagle dogs. Methods and materials In an evaluator‐blinded cross‐over study with an eight week washout period, dogs were treated topically twice daily with W16P576 WECMEP or its vehicle, starting three days before bacterial challenge. On the day of challenge, each dog was treated with two concentrations of a clinical S. pseudintermedius strain on opposite sides of the body. Topical treatment was continued for 11 days and lesions of pyoderma were evaluated and scored for 14 days. Results All dogs developed lesions consistent with bacterial pyoderma. Lesion scores were generally higher on the side inoculated with a higher concentration of bacteria. Treatment with W16P576 significantly reduced lesion development and hastened resolution of lesions, compared to placebo. Conclusion Topical application of W16P576 markedly reduced lesion development in this proof of principle study. Clinical trials are warranted to estimate benefits for dogs with naturally occurring pyoderma under field conditions.

In this pilot trial with a TRPM8 agonist in atopic dogs with pedal pruritus, the twice daily application of a 2% Cryosim-1 cream did not have an antipruritic effect superior to that of its vehicle.