Pharmacology of drugs used in autoimmune dermatopathies in cats and dogs: A narrative review.

Immunosuppressive drugs are the mainstay of treatment for many feline and canine autoimmune skin diseases, either as monotherapy or in combination with other drugs. Treatment with these drugs is often lifelong and may have long-term consequences on the affected animal's overall quality-of-life. Clinicians need to understand the pharmacology of immunosuppressants in planning and executing the treatment regimen for the best possible clinical outcome, as well as reducing the risk of adverse effects. This review paper will focus on the mechanism of action, pharmacokinetics and pharmacodynamics, clinical uses and adverse effects of immunosuppressive drugs used to treat autoimmune dermatoses in cats and dogs. These include glucocorticoids, ciclosporin A, azathioprine, chlorambucil, mycophenolate mofetil, oclacitinib and Bruton's tyrosine kinase inhibitors.

Les médicaments immunosuppresseurs constituent la base de la thérapeutique de nombreuses dermatoses auto­immunes félines et canines, soit en monothérapie, soit en association avec d'autres médicaments. Le traitement par ces médicaments dure souvent toute la vie et peut avoir des conséquences à long terme sur la qualité de vie globale de l'animal affecté. Les cliniciens doivent comprendre la pharmacologie des immunosuppresseurs afin de planifier et de mettre en place le plan thérapeutique, afin d'obtenir le meilleur résultat clinique possible et de réduire le risque d'effets indésirables. Cet article de synthèse cible le mécanisme d'action, la pharmacocinétique et la pharmacodynamie, les utilisations cliniques et les effets indésirables des médicaments immunosuppresseurs utilisés pour traiter les dermatoses auto­immunes chez les chats et les chiens. Ces médicaments comprennent les glucocorticoïdes, la ciclosporine A, l'azathioprine, le chlorambucil, le mycophénolate mofétil, l'oclacitinib et les inhibiteurs de la tyrosine kinase de Bruton.

Os medicamentos imunossupressores são a base do tratamento para muitas doenças de pele autoimunes felinas e caninas, seja em monoterapia ou em combinação com outros medicamentos. O tratamento com esses medicamentos costuma durar toda a vida e pode ter consequências a longo prazo na qualidade de vida geral do animal afetado. Os clínicos precisam compreender a farmacologia dos imunossupressores para planejar e executar o protocolo de tratamento para se obter o melhor resultado clínico possível, assim como reduzir o risco de efeitos adversos. Este artigo de revisão será focado no mecanismo de ação, farmacocinética e farmacodinâmica, indicações clínicas e efeitos adversos de medicamentos imunossupressores usados para tratar dermatoses autoimunes em cães e gatos. Estes incluem glucocorticóides, ciclosporina A, azatioprina, clorambucil, micofenolato de mofetila, oclacitinib e inibidores da tirosina quinase de Bruton.

Los tratamientos inmunosupresores son la línea de tratamiento principal en muchas enfermedades autoinmunes de la piel de perros y gatos, bien como monoterapia o en combinación con otros fármacos. El tratamiento con estos fármacos es a menudo de larga duración o de por vida y puede tener consecuencias adversas de larga duración en la calidad de vida de los animales. Los veterinarios clínicos tienen que entender la farmacología de los inmunosupresores durante la planificación y ejecución de los tratamientos para obtener los resultados más beneficiosos y reducir los efectos adversos. Este artículo de revisión está enfocado en los mecanismos de acción, farmacocinética, farmacodinámica, usos clínicos y efectos adversos de tratamientos inmunosupresores utilizados en perros y gatos para tratar dermatopatías inmunomediadas de la piel. Se incluyen glucocorticoides, ciclosporina A, azatioprina, clorambucilo, mofetil micofenolato, oclacitinib e inhibidores de la tirosina quinasa de Bruton.

A Novel Canine Otoscopy Teaching Model for Veterinary Students.

Otoscopic evaluation using an otoscope is an important tool among the diagnostic modalities for otitis externa and is considered a core component of a canine patient's complete physical examination. Traditionally, otoscopic training in veterinary school involves using live dogs (i.e., laboratory dogs or dogs that are patients of the veterinary teaching hospital). While this approach has its advantages, performing otoscopic examination on live dogs presents several challenges: it requires adequate patient restraint, can cause stress to the dog, and can potentially cause trauma and/or injury to the dog's ear canal when performed by an inexperienced individual. Using an alternative teaching tool for otoscopic evaluation could overcome these challenges and improve veterinary students' learning experience. In this study, we investigated student perceptions of a novel canine teaching model for otoscopic evaluation in first-year veterinary students. The Elnady preservation technique was employed to create a realistic, durable, and flexible model for otoscopic training in a dermatology laboratory session in a first-year veterinary course. Student feedback was assessed on a Likert scale, and overall feedback indicated that students felt that the model was beneficial for skill building and removed many of the stressors incurred with using live animals when training in clinical skills. Most students stated that they would like to have additional similar models incorporated into training and would recommend these models to other students.

Localised erythema multiforme-like reaction confined to a region of clipper burn in a dog.

Localised erythema multiforme (LEM) is only reported to occur in humans and not in domestic species. This case report describes the clinical and histopathological features of LEM-like reaction in a dog, confined to a region of clipper burn.

L'érythème polymorphe localisé (LEM) n'est signalé que chez l'homme et non chez les animaux domestiques. Ce cas clinique décrit les caractéristiques cliniques et histopathologiques d'une réaction de type LEM chez un chien, localisé sur une région de brûlure de tondeuse.

El eritema multiforme localizado (LEM) sólo se ha descrito en seres humanos y no en especies domésticas. Este artículo describe un caso de un perro con una lesión confinada a una zona de quemadura por un rasurador cuyas características clínicas e histopatológicas fueron similares a LEM.

O eritema multiforme localizado (EML) é relatado apenas em humanos e não em animais domésticos. Este relato de caso descreve as características clínicas e histopatológicas de uma reação EML-símile em um cão, limitada a uma região de queimadura por lâmina de tosa.

Determination of the efficacy rate and time-to-efficacy of subcutaneous immunotherapy in dogs with atopic dermatitis.

BACKGROUND: Allergen-specific immunotherapy (ASIT) is reported to have a success rate of 50-70% when given for up to 12 months to dogs with atopic dermatitis (AD). How soon ASIT is clinically effective is unclear. OBJECTIVES: To compare the efficacy rate (ER) and time-to-efficacy (TTE) of various types of subcutaneous immunotherapy (SCIT) administered using conventional dosing regimens using the methodology of a critically appraised topic. METHODS AND MATERIALS: Three databases were searched to extract information on the ER and TTE of SCIT in dogs with AD. Herein, "efficacy" was defined as a ≥50% reduction in pruritus and/or skin lesions, and the TTE as the time needed to achieve such a reduction. RESULTS: We selected 12 publications including 194 dogs. The ER was significantly higher with the polymerised allergoids coupled with nonoxidized mannan than for the "classic" aqueous and alum-precipitated SCIT types. A TTE of three months or shorter was seen in a significantly higher proportion of dogs receiving mannan-couple allergoids, pullulan-conjugated Der f 2 or tyrosine-adjuvanted than aqueous or alum-precipitated SCIT; with the latter two formulations, the TTE might be nine months or longer in ≤20% of atopic dogs. CONCLUSIONS AND CLINICAL RELEVANCE: In spite of the low number of articles available for review and small number of enrolled dogs, novel SCIT regimens appear to have a faster - and possibly higher - efficacy than the currently available aqueous or alum-precipitated formulations. A standardisation of outcome measures for ASIT clearly is needed to allow a more meaningful comparison between SCIT types.

Deep pemphigus (pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus) in dogs, cats and horses: a comprehensive review.

Pemphigus is the term used to describe a group of rare mucocutaneous autoimmune bullous diseases characterized by flaccid blisters and erosions of the mucous membranes and/or skin. When the autoantibodies target desmosomes in the deep layers of the epidermis, deep pemphigus variants such as pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus develop. In this article, we will review the signalment, clinical signs, histopathology and treatment outcome of pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. Canine, feline and equine pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus have many features similar to the human counterpart. These chronic and often relapsing autoimmune dermatoses require aggressive immunosuppressive therapy. In animals, the partial-to-complete remission of pemphigus vulgaris and pemphigus vegetans has been achieved with high dose glucocorticoid therapy, with or without adjunct immunosuppressants; the prognosis is grave for paraneoplastic pemphigus.

Autoimmune diseases affecting skin melanocytes in dogs, cats and horses: vitiligo and the uveodermatological syndrome: a comprehensive review.

Autoimmune dermatoses targeting melanocytes have gained attention in human medicine due to their progressive nature and the social impact suffered by affected individuals. In veterinary medicine, vitiligo and the uveodermatological syndrome are the two autoimmune diseases that are known to affect skin melanocytes.In the first part of this article, we will review the signalment, clinical signs, histopathology and the treatment outcome of vitiligo in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. In a similar fashion, the information on the uveodermatological syndrome in dogs is reviewed and, where relevant, it is compared to the Vogt-Koyanagi-Harada (VKH) syndrome in humans.Canine, feline and equine vitiligo have many features that mirror their human counterparts. The most effective treatment and outcome of vitiligo in animals remain unclear. The canine uveodermatological syndrome resembles the incomplete VKH variant in humans; for affected individuals, an immediate diagnosis and aggressive treatment are crucial to prevent the development of blindness.

Mucous membrane pemphigoid in dogs: a retrospective study of 16 new cases.

BACKGROUND: Mucous membrane pemphigoid (MMP) is a chronic autoimmune subepidermal blistering disease of dogs, cats and humans. OBJECTIVES: The goal of this study was to describe the clinical, histological and immunological features and treatment outcomes of canine MMP. ANIMALS: Sixteen dogs were diagnosed with MMP based on the presence of mucosal- or mucocutaneous-predominant vesiculation and/or ulceration, histological confirmation of subepidermal clefting and an age of disease onset greater than 6 months. RESULTS: Six of 16 dogs (38%) were German shepherd dogs and their crosses. The median age of disease onset was 6 years (range: 1-10 years). At the time of presentation, the dogs exhibited erosions and ulcers in the oral cavity (11 of 16; 69%), nasal (nine of 16; 56%), periocular (eight of 16; 50%) and genital (six of 16; 38%) regions. Haired skin lesions were less frequent (six of 16; 38%) and involved mostly concave pinnae. Information on treatment outcome was available for 11 dogs (69%). A complete remission (CR) of lesions was achieved in 10 of 11 dogs (91%). The median time to CR was 33 weeks (range: 6-64 weeks). Treatment regimens varied widely but six of 10 (60%) dogs received a combination of tetracycline antibiotic and niacinamide alone, or with another drug, at the time of CR. Forty percent of the dogs in which CR had occurred experienced lesion relapse upon drug dose reduction. CONCLUSIONS AND CLINICAL IMPORTANCE: Canine MMP is a chronic and relapsing disease requiring long term treatment. Combination therapy is often needed to achieve CR.

Molecular confirmation of shampoo as the putative source of Pseudomonas aeruginosa-induced postgrooming furunculosis in a dog.

BACKGROUND: An acute onset furunculosis due to Pseudomonas aeruginosa following grooming is a well recognized entity. Although contaminated shampoos have been suspected to be the source of the infection, a molecular confirmation of this association has been missing. OBJECTIVE: This case report describes a dog with postgrooming furunculosis in which Pseudomonas aeruginosa with an identical genetic fingerprint was isolated from the skin lesions as well as from the shampoo used prior to the disease onset. RESULTS: The dog presented for lethargy, anorexia, pain and rapidly progressing skin lesions consistent with haemorrhagic papules, pustules, coalescing ulcers and crusts localized to the dorsal and lateral aspects of the thorax and gluteal region, which developed within 24 h after a bath. Cytology demonstrated suppurative inflammation with occasional intracellular rod-shaped bacteria. Bacterial culture from skin lesions and the shampoo bottle yielded Pseudomonas aeruginosa with an identical pulsed-field gel electrophoresis pattern. Treatment with oral ciprofloxacin and topical antimicrobial shampoo resulted in a complete resolution of skin lesions within eight weeks. CONCLUSION AND CLINICAL IMPORTANCE: Our clinical investigation suggests a link between Pseudomonas-contaminated shampoo and development of postgrooming furunculosis, and underscores the need for hygienic management of shampoos to help limit this disease.

Protozoal nodular dermatitis and panniculitis in a Rottweiler puppy caused by Caryospora bigenetica.

BACKGROUND: Caryospora bigenetica is an intracellular protozoan parasite in snakes and raptors (primary hosts) and rodents (secondary host). Experimental infection has been documented in mice, pigs and goats; natural infection in dogs is rare. OBJECTIVES: To describe the clinical presentation, histological features, treatment and outcome of a case of protozoal nodular dermatitis and panniculitis in a Rottweiler puppy caused by C. bigenetica. RESULTS: The puppy presented with generalized subcutaneous nodules measuring up to 2 cm in diameter. Histopathology revealed marked suppurative to pyogranulomatous dermatitis and panniculitis with intralesional protozoal organism. PCR and DNA sequencing confirmed infection with C. bigenetica. Treatment with a combination of oral trimethoprim-sulfamethoxazole (TMS), pyrimethamine and high-dose clindamycin (20 mg/kg twice daily) resulted in resolution of lesions in 6 weeks. Discontinuation of the treatment 2 weeks later was followed by a rapid relapse of skin lesions. Clindamycin and TMS were restarted and all lesions resolved within 2 weeks; TMS was discontinued 4 weeks later due to adverse effects. The lesions remained in remission for 2 months while the puppy received clindamycin monotherapy before a second relapse of skin lesions occurred. CONCLUSION AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first documentation of the treatment and outcome of C. bigenetica cutaneous infection in a dog. Although remission of clinical signs can be achieved with combination therapy of clindamycin and TMS, long-term management is challenging and relapses should be anticipated.