Prolonged remission after immunosuppressive therapy in six dogs with pemphigus foliaceus

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.

The use of oclacitinib compared to azathioprine in the management of canine pemphigus foliaceus: A retrospective analysis

BACKGROUND

Oclacitinib (Apoquel; Zoetis) has been reported to be beneficial for treating immune-mediated disorders.

HYPOTHESIS/OBJECTIVES

This retrospective study evaluates in which group of dogs [oclacitinib (OC) or azathioprine (AZ)] remission of pemphigus foliaceus (PF) was more effectively achieved with matched induction dosing of glucocorticoids; it further evaluates which group had a higher glucocorticoid-sparing effect.

ANIMALS

Review of 30 medical records of dogs diagnosed with PF presented to a private practice dermatological service.

MATERIALS AND METHODS

Retrospective analysis of dogs diagnosed with PF and treated with OC or AZ in combination with glucocorticoids.

RESULTS

There was no significant difference in the ability to induce remission between AZ and OC groups. In the AZ group, 13 of 15 dogs went into some type of remission (partial or complete), compared with 11 of 15 in the OC group. There was no significant difference between the two groups for the glucocorticoid-sparing effect. The AZ group had an average reduction of 77.9% from the induction glucocorticoid dose, and OC group had an average reduction of 64.4%. One of 15 patients in the AZ group and three of 15 patients in the OC group had a 100% reduction of the glucocorticoid dose.

CONCLUSIONS AND CLINICAL RELEVANCE

These results indicate that OC can be considered as a treatment option for canine PF.

Clinical presentation, treatment and outcome in dogs with pemphigus foliaceus with and without vasculopathic lesions: an evaluation of 41 cases

BACKGROUND

Concurrent vasculopathic lesions in dogs with pemphigus foliaceus (PF) have been observed anecdotally yet not reported in the literature. Any association with prognosis is unclear.

HYPOTHESIS/OBJECTIVES

To compare clinical features and outcome of PF in dogs with and without vasculopathic lesions.

ANIMALS

Archived, formalin-fixed, paraffin-embedded biopsy samples of 41 dogs with PF.

METHODS AND MATERIALS

Archived, formalin-fixed, paraffin-embedded biopsy samples with a histological diagnosis of PF were selected and re-evaluated independently. Dogs were assigned to groups following histological evaluation: Group 1 (no vasculopathic lesions) and Group 2 (vasculopathic lesions present). Group 2 was subdivided into Group 2a (vasculopathic lesions without vasculitis - i.e. vasculopathy) and Group 2b (overt vasculitis). Medical records from identified cases were reviewed retrospectively for data on clinical presentation, treatment and outcome.

RESULTS

Time to remission was longer in Group 2b (93.8 days) compared to Group 1 (41.8 days) (P = 0.047). Dogs in groups 2a and 2b were more likely to have systemic signs of illness at presentation (P = 0.028 and P = 0.032, respectively) compared to Group 1. Dogs in Group 2b were more likely to have adverse effects associated with treatment than dogs in Group 1 (P = 0.004). There were no significant differences in lesion type, distribution, rates of remission, recurrence or corticosteroid dosage between groups.

CONCLUSIONS AND CLINICAL IMPORTANCE

Dogs with PF and concurrent vasculitis took longer to achieve remission and were more likely to have systemic signs of illness or adverse effects associated with treatment than dogs with PF without concurrent vasculopathic lesions.

Feline non-flea induced hypersensitivity dermatitis: clinical features, diagnosis and treatment

PRACTICAL RELEVANCE

Hypersensitivity dermatitis (HD) is often suspected in cats and is mostly caused by insect bites, food or environmental allergens. Cats with non-flea induced HD are reported to present frequently with one or more of the following cutaneous reaction patterns: miliary dermatitis, eosinophilic dermatitis, self-induced symmetrical alopecia or head and neck excoriations/pruritus.

CLINICAL CHALLENGES

None of the above patterns are, however, pathognomonic for non-flea induced HD and the diagnosis of this condition is based on exclusion of diseases presenting similarly and an adequate response to treatment. Therapeutic approaches to affected cats include use of immunomodulatory drugs (ciclosporin, glucocorticoids, antihistamines), hypoallergenic diets and allergen-specific immunotherapy.

EVIDENCE BASE

This review provides an update on the clinical signs, diagnosis and treatment of feline non-flea induced HD. It draws on the findings of a recent large-scale study that described the clinical signs of numerous cats with non-flea HD and has proposed criteria to facilitate the diagnosis of the condition.

Pênfigo foliáceo canino: estudo retrospectivo de 43 casos clínicos e terapia (2000-2005)

No período de agosto de 2000 a julho de 2005 foram atendidos 43 casos de Pênfigo Foliáceo (PF) canino no Serviço de Dermatologia do Hospital Veterinária, Universidade de São Paulo. Com este estudo retrospectivo visou-se atualizar dados referentes à caracterização sexual, definição racial e raça, idade, tipo e topografia lesional, quadro sintomático e resposta aos tratamentos isolados com prednisona e com a associação desta à azatioprina, além de demonstrar o aumento na ocorrência do PF relativamente à série histórica pretérita (1986-2000) do mesmo Serviço.

A review of autoimmune skin diseases in domestic animals: I - superficial pemphigus

In humans, the pemphigus denomination encompasses a group of autoimmune blistering skin diseases with intraepidermal separation resulting from cell-cell detachment by acantholysis. Entities are classified based on the level of blistering in the epidermis, and both superficial (pemphigus foliaceus, IgA pemphigus) and deep (pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus) variants are recognized. In domestic animals, subsets of pemphigus have been recognized since the mid-1970s, and the disease classification resembles that used for human patients. This article reviews up-to-date knowledge on the epidemiology, clinical signs, histopathology, immunopathology and treatment outcome of superficial pemphigus in domestic animals. Detailed information on canine, feline, equine and caprine pemphigus foliaceus, canine and feline pemphigus erythematosus and canine panepidermal pustular pemphigus is provided.

Pemphigus Foliaceus in 91 Dogs

A retrospective study of 91 dogs with pemphigus foliaceus was performed. Clinical signs of the disease included crusts (n=79), pustules (n=36), and alopecia (n=33). Lesions were most common on the trunk (n=53), inner pinnae (n=46), face (n=37), and foot pads (n=32). Cytological evaluation revealed acantholytic keratinocytes in 37 of 48 dogs. Results of combination treatment with prednisolone and azathioprine were comparable to results with prednisolone therapy alone. More than half of the dogs achieved remission with appropriate therapy, and another 25% significantly improved.