Veterinary dermatology最新文献

Background: Janus kinase inhibitors (JAKi) have been shown to reduce pruritus and improve associated inflammatory skin lesions in canine atopic dermatitis (cAD).

Objective: To evaluate the efficacy and safety of ilunocitinib, in comparison to oclacitinib, for the control of cAD in a randomised, blinded trial.

Animals: Three-hundred-and-thirty-eight dogs with cAD.

Materials and methods: Dogs were randomised to receive oclacitinib (0.4-0.6 mg/kg twice daily for 14 days; then once daily) or ilunocitinib (0.6-0.8 mg/kg once daily), for up to 112 days. Owners assessed pruritus using an enhanced Visual Analog Scale (PVAS). Investigators assessed skin lesions using the Canine Atopic Dermatitis Extent and Severity Index, 4th interaction (CADESI-04).

Results: Reduction in pruritus and CADESI-04 scores was similar for both treatment groups from Day (D)0-D14. PVAS scores increased between D14 and D28 for oclacitinib and decreased for ilunocitinib. On D28 to D112, mean PVAS and CADESI-04 scores were significantly lower for ilunocitinib compared to oclacitinib (p ≤ 0.003 and p ≤ 0.023, respectively). On D28 to D112, a greater number of ilunocitinib-treated dogs achieved clinical remission of pruritus (i.e. PVAS score <2). Subjective assessment of overall response was significantly better for ilunocitinib on D28 to D112 (p ≤ 0.002). Both drugs demonstrated similar safety throughout the study.

Conclusions and clinical relevance: Ilunocitinib rapidly and safely controlled signs of cAD. Ilunocitinib demonstrated significantly better control of pruritus and skin lesions compared to oclacitinib, with more dogs achieving clinical remission of pruritus.

Background: In humans, the presence of an even distribution of melanocytes within the epidermal basal layer allows for uniform pigmentation in healthy and young individuals. Moreover, despite high variability in skin colours and tones, interindividual melanocyte density variability is low. However, dogs display a high intraindividual pigmentary variability in different anatomical areas.

Hypothesis/objective: Data on canine melanocytes, including their distribution and density, are limited. This study aimed to assess melanocyte density across different anatomical areas in dogs of various breeds.

Materials and methods: Samples were harvested postmortem from 22 dogs of different breeds and ages. Samples were collected from the following: haired skin (back, ventral abdomen, head and pinnae), oral and conjunctival mucocutaneous junctions, oral mucosa (buccal mucosa, gingiva, palate) and nose. Immunohistochemical investigation using a cocktail containing Melan-A and SOX-10 antibodies was performed to evaluate the melanocytes:keratinocytes ratio (M:K ratio).

Results: Variable melanocyte density was recorded in different anatomical areas, with a higher M:K ratio on the eyelid (median: 1:4; interquartile range [IQR]: 1:3.8-1:5.1) and on the nose (median: 1:6.5; IQR: 1:5.2-1:9.6). Lower ratios were observed on the haired skin, particularly on the head (median: 1:113.6; IQR: 1:37.8-1:255.1).

Conclusions and clinical relevance: Together with different melanocyte densities in different anatomical areas, dogs showed a high interindividual variability, particularly on haired skin. This finding could be associated with colour phenotype, sun exposure, and breed. Variable densities of melanocytes also might justify different incidence of melanocytic tumours in hyperpigmented breeds and in different somatic areas, as well as provide an increased protective effect in chronically sun-exposed areas.

Background: Canine aural cholesteatoma (more appropriately named tympanokeratoma) is an epidermoid cyst whose aetiopathogenesis remains poorly recognised in veterinary medicine. There are a few reports published, possibly because it may be underdiagnosed.

Objectives: To characterise the clinical aspects of dogs with tympanokeratoma, to describe the otoendoscopic, advanced imaging and histopathological findings of tympanokeratoma and to report the best approach to diagnose canine auricular tympanokeratoma in a retrospective study.

Material and methods: Of 890 dogs with suspected tympanokeratoma and otitis media, 100 animals underwent advanced imaging and otoendoscopy at radiology and dermatology reference centres in Brazil.

Results: Most affected dogs were male (71%) neutered (95%) with an average age of 6.8 years. Ninety-one of the 100 affected dogs were brachycephalic. Otitis externa (OE; 81%) was the main non-neurological manifestation observed. The main neurological clinical manifestations observed were: "head tilt" (66%), ataxia (31%) and nystagmus (25%). Advanced imaging findings could not propose a presumptive diagnosis of tympanokeratoma in 60 of 100 (60%) of the dogs. The absence of tympanic membrane and the presence of a dense pearly yellowish material resembling keratin in the tympanic bulla, after myringotomy, was the main otoendoscopic finding. The advanced imaging findings did not correlate with otoendoscopy and histopathological findings in more than half of the dogs.

Conclusions and clinical relevance: Tympanokeratoma should be suspected in brachycephalic dogs with OE and peripheral vestibular syndrome, and samples of keratinous material from the middle ear associated with histopathological results may be the best approach for the diagnosis.

A 3-year-old male sugar glider presented with pruritus and alopecia primarily affecting the back and neck regions. Dermatologic diagnostics ruled out common causes. Skin biopsies revealed cutaneous epitheliotropic T-cell lymphoma, a rare condition in sugar gliders. Despite treatment, the glider's condition worsened, leading to death. This case highlights the importance of thorough diagnostic evaluation in exotic pets.

Background: Allergen immunotherapy is used as aetiological treatment for canine atopic dermatitis (cAD).

Objective: To assess the anti-inflammatory agent-sparing effect over 1 year of immunotherapy using pullulan-conjugated recombinant Der f 2 (rDf2-P).

Animals: Twenty-one privately owned dogs with cAD.

Materials and methods: Dogs with mild clinical signs after ≥4 weeks of anti-inflammatory drug treatment received rDf2-P immunotherapy for 1 year. A monthly medication score (MS) was calculated, and clinical signs were assessed using Canine Atopic Dermatitis Extent and Severity Index (CADESI)-04, cAD Eczema Area and Severity for Shiba Inu and pruritus scores. Serum thymus and activation-regulated chemokine (TARC)/C-C Motif Chemokine Ligand-17 (CCL17) concentrations were assessed at the initial and final doses during the 6-week induction phase and every 3 months for 1 year thereafter in 16 cases.

Results: The mean MS decreased significantly by 43.0% (p = 0.022), 60.9% (p = 0.003), 70.0% (p = 0.0004), 58.7% (p = 0.0004) and 49.3% (p = 0.029) at 2.5, 4.5, 7.5, 10.5 and 13.5 months, respectively. Drug-sparing effects, assessed with MS and adjusted by clinical scores were rated as excellent for 12 (57.1%) and 11 (52.4%) dogs, good for 3 (14.3%) and 1 (4.8%) dogs, fair for 0 and 3 (14.3%) dogs, and poor for 6 (28.6%) and 5 (23.8%) dogs at 4.5 and 13.5 months, respectively. The serum TARC/CCL17 concentrations were significantly lower in the samples with lower CADESI-04 scores (<17) than in those with higher CADESI-04 scores (>17) (p = 0.0002).

Conclusions and clinical relevance: Der f 2-P immunotherapy can lead to a rapid reduction in anti-inflammatory drug use and serve as an effective proactive therapy for cAD.

Background: Epithelial migration (EM) is integral to normal ear structure and function. Glucocorticoids are considered the first-line therapy for various external ear disorders; however, their effects on EM on the tympanic membrane (TM) and the external auditory canal (EAC) are understudied.

Hypothesis/objectives: To test the hypothesis that topical dexamethasone decelerates EM on the TM, this study aimed to evaluate the effects of topical dexamethasone on EM on the TMs of dogs.

Animals: Seven ears of four healthy dogs.

Materials and methods: The migration distance of an ink drop deposited on the posterior quadrant of the pars tensa (TM EM rate) of dogs was calculated over 3 weeks from images captured with a video-otoscope. The results were compared by paired Student's t-test to those obtained from a subsequent experiment in which the same dogs were administered a fresh ink drop at the same position as previously (control group), yet additionally administered 0.1% dexamethasone (0.2 mL/ear) daily for the first 14 days (treatment group).

Results: One of eight ears was excluded because of an anatomical problem. The TM EM rate of the remaining seven ears decreased by 46.74% in the treatment group compared with the control group (p < 0.05).

Conclusions and clinical relevance: Topical dexamethasone decelerates EM on the TM of normal dogs' ears. In turn, it is extrapolated that debris removal from the EAC may be slowed, negatively impacting the EAC environment. Consequently, when dogs with otitis receive topical dexamethasone treatment, additional treatment, such as ear canal cleaning, may be required to minimise the effects of impaired TM EM.

Canine apolipoprotein A-I (ApoA-I) amyloidosis has only been reported as an age-related pulmonary vascular condition. In this report, the authors identified cutaneous ApoA-I amyloidosis within a fibroadnexal hamartoma in a dog. Based on proteomic analysis using mass spectrometry, the mechanism of ApoA-I amyloidogenesis is discussed.

Background: Autosomal recessive ichthyosis leads to structural or biochemical changes that impair skin barrier function.

Hypothesis/objectives: To assess (1) the phenotype and genotype in a litter of Jack Russell Terriers with autosomal recessive congenital ichthyosis (ARCI), and (2) the defective skin barrier and determine if a topical ceramide can modulate the barrier.

Animals: A healthy dam and litter of Jack Russell Terrier puppies (healthy male, affected male and female), one affected adult Jack Russell Terrier and one unrelated healthy Jack Russell Terrier.

Materials and methods: A severe cornification defect was identified via examination of affected puppies. As the phenotype worsened, the affected puppies received a topical application of ω-0-acylceramide for 10 days. Before humane euthanasia, the skin barrier was evaluated via transepidermal water loss (TEWL), corneometry and pH in affected dogs. Genomic testing was performed, and skin samples were analysed by light and electron microscopy.

Results: Affected puppies were homozygous for the 1980 bp LINE-1 insertion in the TGM1 (transglutaminase 1) gene; the unaffected littermate and the dam were heterozygous carriers. ARCI puppies were underweight and had a severe hyperkeratotic phenotype that impaired mobility. TEWL was markedly higher in affected dogs. The cutaneous pH of affected puppies was higher than the normal littermate. Treatment of the skin with ω-0-acylceramide normalised the pH to match the littermate and decreased TEWL. Electron microscopy revealed marked attenuation of the cornified envelope.

Conclusions and clinical relevance: Dogs with TGM1-deficient ARCI have an impaired skin barrier. Topical therapy can partially repair the barrier defect.

Background: Cold atmospheric plasma (CAP) is a new therapeutic tool used to treat various skin diseases in humans and animals.

Objective: To evaluate the effect of CAP in the treatment of canine acute otitis externa (AOE).

Animals: Four client-owned golden retriever dogs with bilateral AOE.

Methods and materials: After cleaning with a commercial ear cleanser, right ears (STANDARD group) were treated with an antibiotic/antifungal/corticosteroid combination and left ears (CAP group) were treated with CAP every three days for a total of four treatments. Cytological score and otitis index score (OTIS)3 were recorded for each ear on Day (D)0, D10 and D15. At D10 and D15, owners and investigators recorded an overall assessment.

Results: In both groups, OTIS3 and cytological score decreased over the study period. The overall assessment scale ranged from moderate to excellent in both groups.

Conclusions and clinical relevance: Cold atmospheric plasma treatment showed equal therapeutic effect compared with a commercial topical anti-inflammatory and antimicrobial ear treatment.

Background: Lokivetmab, a caninised monoclonal antibody against interleukin (IL)-31, is an effective treatment for the pruritus associated with canine atopic dermatitis (cAD).

Objectives: To investigate the efficacy and safety of lokivetmab during long-term treatment defined as at least three consecutive lokivetmab injections in atopic dogs under field conditions. To assess individual factors influencing treatment outcome and adverse events.

Animals: 150 dogs with cAD.

Materials and methods: Medical records of dogs treated with lokivetmab were reviewed, and owners and/or veterinarians were contacted as needed for follow-up. A decrease of the pruritus Visual Analog Scale (PVAS) score by ≥2 or a PVAS score ≤2 after treatment was considered as treatment success. Logistic regression was used to investigate the influence of a variety of factors on outcome: type of cAD (food versus environment), age at first lokivetmab administration, disease chronicity, dosage and/or secondary infection. Any adverse event that occurred during the study period was recorded.

Results: Lokivetmab reduced the PVAS score with long-term use (p < 0.01); the success rate was 53 of 69 total dogs (77%). The probability of treatment failure decreased with increasing treatment duration. None of the factors investigated influenced the treatment outcome. Twelve dogs of 150 (8%) showed adverse events such as gastrointestinal signs or lethargy.

Conclusion and clinical relevance: Lokivetmab appears to be an effective and safe long-term anti-itch therapy for dogs with cAD.