Feline atopic dermatitis: a retrospective study of 45 cases (2001-2012)

Comparison of intradermal and serum testing for environmental allergen-specific immunoglobulin E determination in a laboratory colony of cats with naturally acquired atopic syndrome

BACKGROUND

Allergen testing is used to select antigens included in the desensitisation vaccine. Intradermal skin test (IDT) is the gold standard in cats, yet allergen-specific immunoglobulin (Ig)E serological testing (ASIS) is often used. Feline data are lacking regarding the agreement between IDT and ASIS results.

HYPOTHESIS/OBJECTIVES

The first objective of the study was to establish a colony of cats with naturally acquired feline atopic syndrome (FAS). Further objectives were to define their hypersensitivity disorder to detail the allergen tests results, and to assess similarity between the allergen tests.

ANIMALS

Thirty-five cats with FAS and 10 control cats.

MATERIALS AND METHODS

Enrolled cats went through a five phase-screening and quarantine process before joining the colony. An elimination diet trial was performed on all FAS cats. ASIS and IDT were consecutively performed on all cats under sedation.

RESULTS

Reactions to 34 allergens were compiled for the 45 cats. Global sensitivity and specificity of ASIS were 34.7% and 78.9%, respectively. Only flea (ICC = 0.26, p = 0.040) and Dermatophagoides pteronyssinus (ICC = 0.48, p < 0.001) allergens had a significant intraclass correlation (weak agreement). Two FAS cats had negative tests including one cat with a concomitant food allergy.

CONCLUSIONS AND CLINICAL RELEVANCE

This study depicts the first reported colony of cats with naturally acquired FAS. This is the first feline study to compare and show the poor agreement between allergen tests with a panel of 34 allergens. This colony also harbours two cats with FAS with negative allergen tests. These may represent the first described cats with an intrinsic form of atopic syndrome.

Open trial of recombinant Der f 2 pullulan-conjugated immunotherapy in cats

BACKGROUND

Allermmune HDM (Zenoaq) is a recombinant Dermatophagoides farinae 2 (Der f 2) pullulan-based immunotherapy vaccine whose efficacy on house dust mite allergic dogs has been demonstrated. There is no published information on its use in cats.

OBJECTIVES

The objective of the study was to evaluate the safety and short-term effects of Allermmune HDM in Dermatophagoides farinae (Df)-sensitised cats.

MATERIALS AND METHODS

Eleven cats diagnosed with atopic skin syndrome received Allermmune weekly for six weeks then monthly for three months (total duration 18 weeks). On Weeks 0, 6 and 18 clinical lesions were assessed by the Feline Dermatitis Extent and Severity Index (FEDESI); owners assessed pruritus with a 10-cm Visual Analog Scale (pVAS). Concurrent medication use was recorded. The allergen-specific immunoglobulin (Ig)E were measured before study inclusion with a commercial serological assay.

RESULTS

There were no evident adverse effects. FEDESI and pVAS improved significantly after six weeks (p = 0.001 and p = 0.01, respectively). The pretreatment Df-specific IgE levels were significantly higher in the cats with improved clinical scores than in the cats with no clinical score change (p = 0.009).

CONCLUSIONS AND CLINICAL RELEVANCE

Allermmune HDM may be safe in cats and has the potential to alleviate signs of atopic skin syndrome. Allergen-specific IgE levels may represent an efficacy marker. Controlled studies of longer duration and larger sample size are worth pursuing.

2023 AAHA Management of Allergic Skin Diseases in Dogs and Cats Guidelines

These guidelines present a systematic approach to diagnosis, treatment, and management of allergic skin diseases in dogs and cats. The guidelines describe detailed diagnosis and treatment plans for flea allergy, food allergy, and atopy in dogs and for flea allergy, food allergy, and feline atopic skin syndrome in cats. Management of the allergic patient entails a multimodal approach with frequent and ongoing communication with the client. Obtaining a comprehensive history is crucial for diagnosis and treatment of allergic skin diseases, and the guidelines describe key questions to ask when presented with allergic canine and feline patients. Once a detailed history is obtained, a physical examination should be performed, a minimum dermatologic database collected, and treatment for secondary infection, ectoparasites, and pruritus (where indicated) initiated. The process of diagnosing and managing allergic skin disease can be prolonged and frustrating for clients. The guidelines offer recommendations and tips for client communication and when referral to a dermatologist should be considered, to improve client satisfaction and optimize patient outcomes.

Recent advance in mesenchymal stem cells therapy for atopic dermatitis

Mesenchymal stem cells (MSCs) are multipotent cells found in a variety of tissues in the body, including but not limited to bone marrow, adipose tissue, umbilical cord, and umbilical cord blood. Given their immunomodulatory effect and ability to be readily isolated from several tissues, they have great potential to be used as a therapeutic agent in a variety of immune-mediated disorders. Atopic dermatitis (AD) is a persistent and relapsing immune skin condition that has recently become more common in several species such as humans, canines, equines, and felines. The use of MSCs to treat AD has piqued the great interest of researchers in recent years. In this article, we review the recent understanding of AD pathology and advances in preclinical and clinical studies of MSCs, MSCs-derived conditional media and exosomes as therapeutic tools to treat AD.

Staphylococci isolated from cats in Italy with superficial pyoderma and allergic dermatitis: Characterisation of isolates and their resistance to antimicrobials

BACKGROUND

In cats, superficial pyoderma traditionally is considered rare and few reports are available. There is a particular lack of studies concerning Staphylococcus species associated with pyoderma in subjects affected by allergic skin diseases.

HYPOTHESIS/OBJECTIVES

(i) To evaluate the association between Staphylococcus spp. and superficial pyoderma in allergic cats and (ii) to characterise isolated staphylococci and analyse their antimicrobial resistance patterns.

ANIMALS

Forty-one cats with allergic dermatitis and superficial pyoderma in Italy.

MATERIALS AND METHODS

Skin swabs were cultured for the isolation of Staphylococcus spp. Species identification was performed by matrix-assisted laser desorption/ionisation time of flight mass spectrometry and 16S-rRNA sequencing. Staphylococcus aureus isolates were further characterised by staphylococcal protein A gene-typing. Antimicrobial susceptibility was performed by the disk diffusion method.

RESULTS

Staphylococci were isolated from 36/41 cats sampled and 39 different isolates were identified. Uneven distribution of staphylococcal species was observed among different body locations. The 39 isolates were S. aureus (n = 15), S. felis (n = 10), S. pseudintermedius (n = 8) and other staphylococci (n = 6). Eight different S. aureus spa-types associated with human clonal complexes were identified. Antimicrobial resistance was observed to penicillin (56.4%), tetracycline (46.2%), enrofloxacin (33.3%), erythromycin (28.2%), amikacin (25.6%), clindamycin (23.1%), marbofloxacin (15.4%), gentamicin (12.8%), trimethoprim-sulfamethoxazole (10.3%), chloramphenicol (7.7%) and cefoxitin/oxacillin (5.1%). Fifteen isolates (38.4%) were multidrug-resistant while meticillin resistance was associated only with S. pseudintermedius.

CONCLUSIONS AND CLINICAL RELEVANCE

These results confirm that S. aureus, S. pseudintermedius, and S. felis are frequently associated with superficial pyoderma in allergic cats. Semi-synthetic penicillins remain a suitable first-line treatment in this study, yet the high prevalence of antimicrobial resistant isolates suggests that antimicrobial susceptibility testing should be performed routinely.

Efficacy of oclacitinib for the control of feline atopic skin syndrome: correlating plasma concentrations with clinical response

OBJECTIVES

The aim of this study was to assess the efficacy of a new therapeutic regimen of oclacitinib for the control of feline atopic skin syndrome (FASS) and to correlate plasma levels of this drug with clinical effects.

METHODS

Twenty-eight client-owned cats with a clinical diagnosis of FASS were recruited. Oclacitinib was administered at 1 mg/kg q12h for 2 weeks and then at 1 mg/kg q24h for a further 2 weeks. At the study outset (D0), and 7 (D7) and 28 (D28) days after starting treatment, clinical lesions were assessed using a validated scoring system (SCORing Feline Allergic Dermatitis [SCORFAD]) and pruritus was graded via an adapted visual analogue scale (PVAS). At the same time points, plasma oclacitinib levels and haematological variables were measured.

RESULTS

Among 18 cats completing the study, PVAS and SCORFAD improved by ⩾50% in 61% and 88% of animals, respectively. Mean PVAS decreased significantly between D0 and D7 and between D0 and D28 (both P <0.001) but not between D7 and D28. Likewise, mean SCORFAD values decreased significantly between D0 and D7 and between D0 and D28 (both P <0.001) but not between D7 and D28. On D7 and D28, plasma oclacitinib concentrations varied widely from 0 to 1443.2 ng/ml and from from 0 to 1177.7 ng/ml, respectively. Oclacitinib concentrations showed no correlation with clinical effects (SCORFAD and PVAS).

CONCLUSIONS AND RELEVANCE

Oclacitinib emerged as being safe and effective to control clinical signs of FASS. A mean dose of 1 mg/kg, even without extending twice-daily treatment beyond the first 2 weeks, could be a suitable therapeutic regimen. Plasma drug levels did not seem useful to predict clinical response during treatment.

THE USE OF INTRADERMAL ALLERGY TESTING FOR ALLERGIC DERMATITIS IN PTEROPID BATS AND TREATMENT WITH ALLERGEN SPECIFIC IMMUNOTHERAPY: A CASE SERIES

This case series describes the diagnosis of allergic dermatitis and management with allergen-specific immunotherapy (ASIT) based on intradermal allergy testing (IDAT) and adjunctive medical therapy in six pteropid bats; five large flying foxes (Pteropus vampyrus); and one variable flying fox (Pteropus hypomelanus). The cases ranged from 2 to 15 yr of age at the time of presentation. Clinical signs varied between individuals and included moist ulcerative cutaneous lesions in nonhaired skin, blepharoconjunctivitis, alopecia, and pruritus. All bats underwent IDAT under general anesthesia, and reactive allergens included a mixture of grasses, trees, weeds, and biting insects. Three of the six cases (50%) had reformulation of the ASIT before control of clinical signs was seen, and two bats were treated with the addition of oclacitinib (Apoquel). Severe adverse effects were not identified; however, one bat had self-limiting swelling at the immunotherapy injection site. All six cases showed improvement of clinical signs and perceived comfort level, including in subsequent allergy seasons.

Outcomes and complications of anal sacculectomy for non-neoplastic anal sac disease in cats: 8 cases (2006-2019)

OBJECTIVES

To describe the features of non-neoplastic anal sac disease in cats, the surgical procedure, complications, surgical outcome and prognosis compared to well-established data for anal sacculectomy in canine patients.

MATERIALS AND METHODS

A retrospective review of medical records of cats undergoing anal sacculectomy for non-neoplastic disease between 2006 and 2019.

RESULTS

Eight cats were included in the study of which four of eight developed minor and self-limiting complications including defaecatory complications in three cases and superficial corneal ulceration in one case. No cat developed permanent faecal incontinence. No long-term postoperative complication was recorded. Median surgical time was 35 minutes (range, 20 to 42). Median hospitalisation time was 1.5 days (range, 1 to 4). The incidence of short-term minor complications is higher than previously reported in dogs, although this might be in agreement with a reported higher incidence in dogs smaller than 15 kg.

CLINICAL SIGNIFICANCE

Anal sacculectomy for non-neoplastic anal sac disease is a safe procedure in cats with relatively high rate of short-term but self-limiting, minor, postoperative complications.

Feline allergic diseases: introduction and proposed nomenclature

BACKGROUND

Feline allergic diseases present as challenging problems for clinicians, not least because of the number of reaction patterns of the feline skin, none of which are specific for allergy. Furthermore, there is some controversy over the nomenclature that should be used in their description.

OBJECTIVES

To review the literature, assess the status of knowledge of the topic and the extent to which these diseases could be categorized as atopic in nature, and make recommendations concerning nomenclature.

METHODS

Atopic diseases in humans and cats were researched. A comparison then was made of the essential features in the two species.

RESULTS

There were sufficient similarities between human atopic diseases and the manifestations of feline diseases of presumed allergic aetiology to justify the use of "atopic" to describe some of the feline conditions affecting the skin, respiratory and gastrointestinal tract. However, none of the allergic skin diseases showed features consistent with atopic dermatitis as described in man and the dog.

CONCLUSIONS AND CLINICAL IMPORTANCE

The term "Feline Atopic Syndrome" (FAS) is proposed to encompass allergic diseases of the skin, gastrointestinal tract and respiratory tract, and "Feline atopic skin syndrome" (FASS) proposed to describe allergic skin disease associated with environmental allergies. We are not aware of any adverse food reactions in cats that are attributable to causes other than immunological reactions against the food itself. We therefore propose an aetiological definition of "Food Allergy" (FA) to describe such cases.

Oral dexamethasone sodium phosphate solution significantly reduces pruritus and clinical lesions in feline hypersensitivity dermatitis: an open-label study

BACKGROUND

There are no liquid oral glucocorticoids labelled for management of pruritus and clinical lesions of feline hypersensitivity dermatitis (feline HD).

HYPOTHESIS

First, to demonstrate that dexamethasone sodium phosphate (DexSP, DexajectSP, Henry Schein; Dublin, OH, USA; 4 mg/mL), an intravenous glucocorticoid, can be absorbed by healthy cats when administered orally. Second, to demonstrate the efficacy of orally administered DexSP for reducing pruritus and clinical lesions in patients with feline HD.

ANIMALS

Seven healthy and 12 client-owned cats with HD.

METHODS AND MATERIALS

Healthy cats were administered a single dose of 0.2 mg/kg DexSP p.o. and serum concentrations were measured using enzyme-linked immunosorbent assay (ELISA). Feline HD patients were assessed with SCORing Feline Allergic Dermatitis (SCORFAD) and pruritus Visual Analog Scale (pVAS) at Visit 1 (V1) and after 20-31 days of receiving 0.2 mg/kg/day DexSP p.o. (V2). Complete blood cell counts, serum chemistry profile, and urinalysis were performed in 50% of feline HD patients at both visits.

RESULTS

Healthy cats had detectable serum concentrations of DexSP following oral administration; concentrations ranged from 0.7 to 92.3 ng/mL. Feline HD patients showed significant decreases in SCORFAD and pVAS scores from V1 to V2.

CONCLUSIONS

DexSP was absorbed when administered orally to healthy cats and 0.2 mg/kg/day DexSP is an efficacious dose to rapidly improve the pruritus and clinical lesions associated with feline HD.

Characterisation of the serum cytokine profile in feline atopic skin syndrome

BACKGROUND

Feline atopic skin syndrome (FASS) is a pruritic and inflammatory skin disease commonly encountered in cats. Three previous reports evaluated cytokine immune activation in cats diagnosed with feline allergic dermatitis. However, no significant upregulations were observed in allergic cats compared to healthy controls.

HYPOTHESIS/OBJECTIVE

To evaluate differences in the serum cytokine profile of cats diagnosed with FASS compared to healthy cats, and correlate serum markers with the extent of FASS skin disease using clinical scoring systems.

ANIMALS

Thirteen client-owned FASS cats and 12 healthy control cats.

METHODS AND MATERIALS

Thirteen cytokine and chemokines from the serum of FASS cats and healthy controls were analysed using a commercially available feline-specific multiplex assay.

RESULTS

Patients with FASS had a significant increase in serum concentrations of interferon-gamma (IFN-γ), interleukin (IL)-2, IL-13 and IL-18. In addition, cytokine/chemokines involved in inflammation and chemotaxis [IL-8, C-C Motif Chemokine Ligand (CCL)5, CCL2 and CXCL12], as well as growth factors, stem cell factor and Fms-related tyrosine kinase 3 ligand (Flt3L), also were significantly elevated. A significant positive correlation (r = 0.64) between the serum levels of Flt3L and Scoring Feline Allergic Dermatitis (SCORFAD) score was observed.

CONCLUSIONS

These results demonstrate the activation of a broad array of immune secretory cytokines in the serum of cats with FASS, which are largely associated with a mixed Th1 and Th2 inflammatory response along with specific growth factors. Further larger-sample studies are needed to assess the modulation of serum biomarkers in FASS by pharmacological/therapeutic interventions.

Chronic Otitis in Cats: Clinical management of primary, predisposing and perpetuating factors

PRACTICAL RELEVANCE

Chronic otitis can be one of the most frustrating diseases to manage for a small animal practitioner. While it occurs less commonly in the cat than the dog, it is no less challenging. The purpose of this review is to discuss the common and uncommon causes of chronic otitis in the cat within the clinical framework used for diagnosis and treatment. The focus is on diseases that affect the ear canal, rather than those restricted to the pinnae.

CLINICAL CHALLENGES

Otitis is multifactorial, which complicates management. A common clinical mistake is to focus solely on treating the infection present. Only by addressing all factors will a clinician successfully control chronic otitis. For the purposes of this review, the authors have adopted the established model of separating primary, predisposing and perpetuating causes of otitis. Primary factors are those that directly cause otitis (inflammation); predisposing factors are those that put the patient at risk for development of otitis; and perpetuating factors are those that result in ongoing clinical signs of otitis or that prevent clinical resolution.

AUDIENCE

This review is aimed at veterinarians who treat cats and particularly those with an interest in feline dermatology and otology.

EQUIPMENT

While many practitioners rely on a hand-held otoscope, a video-otoscope can be very helpful for the diagnosis and treatment of chronic otitis.

EVIDENCE BASE

This review presents up-to-date information regarding the diagnosis and treatment of chronic otitis in cats, with emphasis on the most recent peer-reviewed literature.

Treatment of the feline atopic syndrome - a systematic review

BACKGROUND

Feline allergic skin disease and asthma occur regularly in small animal practice.

OBJECTIVES

To provide evidence-based recommendations for small animal practitioners on the treatment of feline atopic syndrome (FAS).

METHODS AND MATERIALS

The authors reviewed the literature available before February 2020, prepared a detailed evidence-based literature review and made recommendations based on the evaluated evidence.

RESULTS

Sixty-six papers and abstracts were identified describing treatment interventions for FAS and evaluated to establish treatment recommendations. For many treatment options, the papers were retrospective, open studies or case reports.

CONCLUSION AND CLINICAL RELEVANCE

In this review, there was good evidence for the efficacy of systemic glucocorticoids and ciclosporin, and limited evidence for the efficacy of topical glucocorticoids, oclacitinib and allergen-specific immunotherapy in feline atopic skin syndrome. Evidence pointed to low-to-moderate efficacy for antihistamines, fatty acids and palmitoyl ethanolamide. In feline asthma, there was good evidence for the efficacy of oral and inhaled glucocorticoids, and limited evidence of moderate efficacy for allergen-specific immunotherapy. Evidence supported low-to-moderate efficacy of mesenchymal stem cells, inhaled lidocaine and oclacitinib as treatments for feline asthma. For almost all therapeutic options (with the exception of glucocorticoids and ciclosporin), more randomised controlled trials are needed.

Immunopathogenesis of the feline atopic syndrome

BACKGROUND

Feline diseases of possible allergic origin with similar clinical phenotypes can have a varied underlying pathogenesis. Clinical phenotype, precise aetiology and underlying immunopathogenesis all need to be considered if advances in this neglected area of dermatology are to be made.

OBJECTIVES

To document the status of research into the immunopathogenesis of the diseases that fall within the spectrum of the feline atopic syndrome (FAS ), to summarize the conclusions, identify the limitations and recommend future research directions.

METHODS AND MATERIALS

A search of the literature was undertaken. The strengths and validity of the data and the contributions to our current understanding of the immunopathogenesis were analysed. Skin diseases of presumed allergic aetiology and asthma were assessed separately, as was the role of antibodies, cells and cytokines in each.

RESULTS

The research varied in its quality and its impact often was limited by a failure to employ strict criteria in case selection. This reflected the difficulties of skin reaction patterns associated with a number of inciting causes. Research into feline asthma was handicapped by the difficulties of investigating clinical material, and much of the useful information was derived from experimental models.

CONCLUSIONS AND CLINICAL IMPORTANCE

The evidence reviewed was supportive of a role for immunoglobulin (Ig)E in the pathogenesis of both feline atopic skin syndrome (FASS) and asthma, albeit not strongly so. The inflammation noted in both FASS and asthma is accompanied by eosinophils and lymphocytes, and these findings, together with the cytokine expression, are suggestive in some (not all) cats of T-helper type 2 immune dysregulation.

Clinical signs and diagnosis of feline atopic syndrome: detailed guidelines for a correct diagnosis

BACKGROUND

Feline atopic syndrome (FAS) describes a spectrum of hypersensitivity disorders characterised by highly diverse clinical presentations including skin, gastrointestinal and respiratory systems. Among these disorders is feline atopic skin syndrome (FASS), in which hypersensitivity is typically associated with environmental allergens, although food allergy may coexist. Involvement of other organ systems (e.g. asthma) also may occur. Because of its highly heterogeneous clinical presentation, diagnosis of FASS can be challenging.

OBJECTIVES

A subgroup of the International Committee on Allergic Diseases of Animals was tasked to summarise the most current information on the clinical presentations of FASS and to develop diagnostic guidelines.

METHODS AND MATERIALS

Online citation databases and abstracts from international meetings were searched for publications related to feline allergic conditions. These were combined with expert opinion where necessary.

RESULTS

A total of 107 publications relevant to this review were identified. Compilation of these data enabled development of a detailed description of the clinical features of FASS and development of guidelines focusing on systematic elimination of other skin conditions with similar clinical characteristics. As allergen tests are frequently used by dermatologists to support a clinical diagnosis of FASS, a brief review of these methodologies was also performed.

CONCLUSIONS AND CLINICAL IMPORTANCE

In a similar way to atopic dermatitis in dogs, FASS is a clinical diagnosis based on the presence of compatible clinical signs and exclusion of other diseases with similar clinical features. Elimination or exclusion of fleas/flea allergy, other parasites, infections and food allergy is mandatory before reaching a diagnosis of FASS.

Clinical efficacy of sublingual allergen-specific immunotherapy in 22 cats with atopic dermatitis

BACKGROUND

Sublingual immunotherapy (SLIT) has been deployed in humans and dogs; to the best of the authors' knowledge, there are no published studies about the use of SLIT in cats.

OBJECTIVES

Evaluate the clinical efficacy of SLIT in atopic cats sensitized to dust and storage mites, assessing immunological changes associated with SLIT treatment.

ANIMALS

Twenty-two client-owned cats with clinical signs compatible with feline atopic dermatitis (fAD) and serum allergen-specific immunoglobulin (Ig)E against house dust and storage mites.

METHODS AND MATERIALS

Prospective, multicentre, open-label clinical trial. Individualized mite-specific SLIT was administered orally for 12 months. All cats underwent clinical examination to record SCORing feline allergic dermatitis (SCORFAD), pruritus Visual Analog Scale (pVAS) and serum allergen-specific IgE and IgG, every three months for 12 months.

RESULTS

Sixteen of 22 cats (73%) completed the study and three of six cats withdrawn from the study were included in an intention-to-treat analysis. SCORFAD and pVAS values decreased significantly from baseline (T0) to the third month of treatment (P = 0.0004 and P = 0.0013, respectively), with median total values ranging from 19 (6-44) (T0) to 2.5 (0-17) (T12) (P = 0.0001), and from 8 (6-10) (T0) to 2.3 (0-8) (T12) (P = 0.0001), respectively. Allergen-specific IgE values decreased significantly from the ninth month (T9) of treatment (P = 0.0032), with median scores decreasing from 56 (12-729) (T0) to 34 (0-158) (T12) (P = 0.0208). No significant differences in allergen-specific IgG values were observed throughout the study. No adverse effects related to the use of SLIT were reported.

CONCLUSIONS AND CLINICAL IMPORTANCE

Sublingual immunotherapy should be considered a rapid, effective, safe and well-tolerated treatment in cats with feline atopic dermatitis fAD.

A survey of primary care practitioners' referral habits and recommendations of allergen-specific immunotherapy for canine and feline patients with atopic dermatitis

BACKGROUND

A recent pilot study of primary care veterinarians' attitudes regarding canine atopic dermatitis and initiation of allergen-specific immunotherapy (ASIT) revealed several barriers to specialist referral (in the USA) and use of ASIT as a treatment modality.

HYPOTHESIS/OBJECTIVES

The primary objective was to collect data on referral habits and ASIT practices among a much larger cohort of primary care veterinarians located around the world, and to explore barriers to referral and management of atopic diseases of dogs and cats with ASIT.

METHODS AND MATERIALS

An online survey, administered through the Veterinary Information Network (VIN, Davis, CA, USA), asked participants to self-report their referral habits and immunotherapy recommendations, and rate barriers and motivating factors using Likert-scale responses.

RESULTS

Of 827 survey responses, 97.6% identified as primary care practitioners. A larger number of practitioners (84.5%) reported seeing atopic dogs often, compared with atopic cats (9.7%). Fewer of these veterinarians (56.6%) referred atopic cats for specialist care, compared to atopic dogs (73.5%). Timely communication, sharing long-term management of the case, and provision of local continuing education were identified as factors associated with increased willingness to refer. A higher proportion of practitioners reported recommending ASIT for dogs (44.3%) than for cats (16.0%). Only 56.0% of respondents considered success rates of ASIT to be acceptable, while 27.9% were neutral on the topic.

CONCLUSIONS AND CLINICAL RELEVANCE

Dermatology specialists might build stronger relationships with referring veterinarians through timely case follow-up and provision of continuing education regarding the long-term benefits of ASIT and symptomatic management practices.

Biology, diagnosis and treatment of Malassezia dermatitis in dogs and cats Clinical Consensus Guidelines of the World Association for Veterinary Dermatology

BACKGROUND

The genus Malassezia is comprised of a group of lipophilic yeasts that have evolved as skin commensals and opportunistic cutaneous pathogens of a variety of mammals and birds.

OBJECTIVES

The objective of this document is to provide the veterinary community and other interested parties with current information on the ecology, pathophysiology, diagnosis, treatment and prevention of skin diseases associated with Malassezia yeasts in dogs and cats.

METHODS AND MATERIAL

The authors served as a Guideline Panel (GP) and reviewed the literature available prior to October 2018. The GP prepared a detailed literature review and made recommendations on selected topics. The World Association of Veterinary Dermatology (WAVD) Clinical Consensus Guideline committee provided guidance and oversight for this process. The document was presented at two international meetings of veterinary dermatology societies and one international mycology workshop; it was made available for comment on the WAVD website for a period of six months. Comments were shared with the GP electronically and responses incorporated into the final document.

CONCLUSIONS AND CLINICAL IMPORTANCE

There has been a remarkable expansion of knowledge on Malassezia yeasts and their role in animal disease, particularly since the early 1990's. Malassezia dermatitis in dogs and cats has evolved from a disease of obscurity and controversy on its existence, to now being a routine diagnosis in general veterinary practice. Clinical signs are well recognised and diagnostic approaches are well developed. A range of topical and systemic therapies is known to be effective, especially when predisposing factors are identified and corrected.

Use of maropitant for the control of pruritus in non-flea, non-food-induced feline hypersensitivity dermatitis: an open-label, uncontrolled pilot study

OBJECTIVES

Non-flea, non-food-induced hypersensitivity dermatitis (NFNFIHD) is a common inflammatory and pruritic skin disease in cats. When avoidance and conventional systemic immunosuppressive treatments fail to control the clinical signs, there are limited treatment options. The aim of this study was to evaluate the efficacy and tolerability of maropitant in feline NFNFIHD.

METHODS

In an open-label, uncontrolled study, cats with proven non-seasonal NFNFIHD were treated with maropitant 2 mg/kg PO q24h for 4 weeks. Clinical lesions were evaluated with the Scoring Feline Allergic Dermatitis (SCORFAD) system and pruritus was evaluated with a 10 cm visual analogue scale (VAS) before and at the end of the study. Owners assessed global efficacy and tolerability with a 4-point scale at the end of the study. Adverse events and body weight changes were recorded.

RESULTS

Twelve cats were treated with a mean initial maropitant dose of 2.22 mg/kg PO q24h. The treatment decreased both SCORFAD and pruritus VAS (pVAS) scores in all cats except one, in which only pruritus was reduced. The efficacy and the tolerability of the treatment were judged as excellent or good by 83.3% of owners. Treatment did not cause any side effects other than, in a few cases, short-time, self-limiting sialorrhoea.

CONCLUSIONS AND RELEVANCE

Maropitant seems to be an effective, well-tolerated therapeutic option to control pruritus in cats. Caution is needed in interpreting the results as the pVAS score system has not yet been validated in cats and the trial was uncontrolled. A further, controlled study is required to confirm our findings.

Effect of dietary supplementation with ultramicronized palmitoylethanolamide in maintaining remission in cats with nonflea hypersensitivity dermatitis: a double-blind, multicentre, randomized, placebo-controlled study

Background

Feline nonflea hypersensitivity dermatitis (NFHD) is a frequent cause of over‐grooming, scratching and skin lesions. Multimodal therapy often is necessary.

Hypothesis/Objectives

To investigate the efficacy of ultramicronized palmitoylethanolamide (PEA‐um) in maintaining methylprednisolone‐induced remission in NFHD cats.

Animals

Fifty‐seven NFHD cats with nonseasonal pruritus were enrolled originally, of which 25 completed all study requirements to be eligible for analysis.

Methods and materials

Cats were randomly assigned to PEA‐um (15 mg/kg per os, once daily; n = 29) or placebo (n = 28) while receiving a 28 day tapering methylprednisolone course. Cats responding favourably to methylprednisolone were then administered only PEA‐um (n = 21) or placebo (n = 23) for another eight weeks, followed by a four week long treatment‐free period. Cats were maintained in the study until relapse or study end, whichever came first. Primary outcome was time to relapse. Secondary outcomes were pruritus Visual Analog Scale (pVAS), SCORing Feline Allergic Dermatitis scale (SCORFAD) and owner Global Assessment Score (GAS).

Results

Mean relapse time was 40.5 days (±7.8 SE) in PEA‐um treated cats (n = 13) and 22.2 days (±3.7 SE) for placebo (n = 12; P = 0.04). On Day 28, the severity of pruritus was lower in the PEA‐um treated cats compared to placebo (P = 0.03). Mean worsening of pruritus at the final study day was lower in the PEA‐um group compared to placebo (P = 0.04), whereas SCORFAD was not different between groups. Mean owner GAS at the final study day was better in the PEA‐um than the placebo‐treated group (P = 0.05).

Conclusion and clinical importance

Ultramicronized palmitoylethanolamide could represent an effective and safe option to delay relapse in NFHD cats.

Critically appraised topic on adverse food reactions of companion animals (7): signalment and cutaneous manifestations of dogs and cats with adverse food reactions

BACKGROUND

Outside of pruritus, there is no clear consensus on the nature and prevalence of cutaneous manifestations of adverse food reactions (AFRs) in dogs and cats.

RESULTS

We searched two databases on August 7, 2018, for articles reporting detailed data on the signalment and clinical signs of at least one dog or cat with a cutaneous AFR (CAFR). We identified 233 and 407 citations from which were selected 32 articles reporting original information. Twenty-two articles included data on 825 dogs with CAFRs. The reported age of onset varied from less than one to 13 years of age; a beginning of signs by 6 or 12 months of age was noted in 22 to 38% of dogs, respectively. The female-to-male ratio also varied considerably. Four breeds (German shepherd dogs, West Highland white terriers, Labrador and golden retrievers) accounted for about 40% of affected dogs. Most dogs diagnosed with a CAFR were pruritic, most often in a generalized pattern, with the ears, feet, and abdomen also being frequently affected; the perineum was uncommonly targeted, however. Canine CAFRs presented mainly as recurrent bacterial skin infections, otitis externa and atopic dermatitis. Twelve articles reported novel information on 210 cats with this syndrome. There was no apparent breed and gender predisposition for feline CAFRs, but cats appeared to develop signs later than dogs with the same syndrome. Most cats with a CAFR were pruritic, especially on the head/face and neck, with the abdomen and ears also commonly involved. Symmetric self-induced alopecia, a head-and-neck self-traumatic dermatitis, miliary dermatitis and variants of eosinophilic diseases were the most common manifestations of feline CAFRs.

CONCLUSIONS

CAFRs affect dogs and cats of any age, any breed, and both genders, with the proportion of juvenile dogs diagnosed about twice that of cats. There are no reliable breed predisposition data. Most patients are pruritic, with half the dogs having generalized pruritus and half the cats scratching their face/head or neck. Canine CAFRs most often manifest as bacterial skin infections, otitis externa or atopic dermatitis; cats with CAFRs will exhibit the expected clinical phenotypes associated with feline hypersensitivity dermatitides.

Atopic dermatitis in cats and dogs: a difficult disease for animals and owners

The purpose of this review article is to give an overview of atopic dermatitis in companion animals and of recent developments including knowledge on immunological background, novel treatment options and difficulties in disease management. The prevalence of hypersensitivities seems to be increasing. The pathogenetic mechanisms are not fully understood, yet multiple gene abnormalities and altered immunological processes are involved. In dogs and cats, the diagnosis of atopic dermatitis is based on history, clinical examination and exclusion of other differential diagnoses. Intradermal testing or testing for serum allergen-specific Immunoglobulin E is only used to identify allergens for inclusion in the extract for allergen immunotherapy. Symptomatic therapy includes glucocorticoids, ciclosporin, essential fatty acids and antihistamines. A selective janus kinase 1 inhibitor and a caninized monoclonal interleukin-31 antibody are the newest options for symptomatic treatment, although longterm effects still need to be assessed. The chronic and often severe nature of the disease, the costly diagnostic workup, frequent clinical flares and lifelong treatment are challenging for owners, pets and veterinarians. Patience and excellent communication skills are needed to achieve a good owner compliance and satisfactory clinical outcome for the animal.

Allergen immunotherapy in people, dogs, cats and horses - differences, similarities and research needs

In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a production of "blocking" IgG antibodies with AIT are similar mechanisms in human beings and dogs with allergic diseases. Although subcutaneous immunotherapy is used for atopic dermatitis in cats, data for its efficacy are sparse. There is some evidence for successful treatment of feline asthma with AIT. In horses, most studies evaluate the effect of AIT on insect hypersensitivity with conflicting results although promising pilot studies have demonstrated the prophylaxis of insect hypersensitivity with recombinant antigens of biting midges (Culicoides spp.). Optimizing AIT using allergoids, peptide immunotherapy, recombinant allergens and new adjuvants with the different administration types of allergen extracts will further improve compliance and efficacy of this proven treatment modality.

Cannabinoid receptor types 1 and 2 and peroxisome proliferator-activated receptor-α: distribution in the skin of clinically healthy cats and cats with hypersensitivity dermatitis

BACKGROUND

Cannabinoid receptors and peroxisome proliferator-activated receptor-alpha (PPAR-α) are gaining recognition as potential therapeutic targets for the treatment of skin disorders.

HYPOTHESIS/OBJECTIVES

The aim of this study was to investigate the distribution of cannabinoid type 1 and 2 receptors (CBR1 and CBR2) and PPAR-α in feline skin and verify whether changes occur in the course of hypersensitivity dermatitis.

ANIMALS

Twelve privately owned cats. Skin samples were obtained from five healthy cats with no skin lesions and seven cats clinically diagnosed with hypersensitivity dermatitis.

METHODS AND MATERIALS

Haematoxylin and eosin stained skin sections were investigated for histopathological changes. Indirect immunofluorescence for CBR1, CBR2 and PPAR-α was performed on paraffin-embedded sections, and antibody specificity tested by Western blot analysis.

RESULTS

Skin samples from cats with hypersensitivity dermatitis were all histopathologically diagnosed with eosinophilic dermatitis. CB receptors and PPAR-α were distributed throughout the skin in both healthy and allergic cats. In normal feline skin, these receptors were mainly distributed in the epithelial compartment. Receptor expression increased in hypersensitivity compared to healthy skin, with the main distribution changes being suprabasal for CBR1, dermal for CBR2 and marked expression of PPAR-α in hyperplastic epidermis and perivascular infiltrate.

CONCLUSIONS AND CLINICAL IMPORTANCE

Increased expression of cannabinoid receptors in the skin of cats with hypersensitivity dermatitis suggests an endogenous protective strategy and may support the use of natural cannabinoid receptor or PPAR-α agonists to treat feline hypersensitivity dermatitis.

Ciclosporin and the cat: Current understanding and review of clinical use

Practical relevance: Ciclosporin (CsA) is a systemic immuno-modulatory drug widely used to treat immune-mediated diseases in humans and veterinary species. CsA was registered for use in cats in the USA and Europe in 2011, and is indicated for the treatment of chronic allergic dermatitis at a recommended daily dose of 7 mg/kg PO.

AUDIENCE

This review will be of interest to all veterinarians working with cats, given the wide range of potential applications of CsA and its safety profile. Although the drug is currently only licensed to treat chronic allergic dermatitis in cats, a small number of reports describe its use in non-dermatological conditions. Evidence base: This article reviews the mechanism of action, pharmacokinetics, drug interactions, adverse effects and clinical use of CsA, both for the licensed indication and for off-label use in the feline patient. Information presented has been summarised from the existing literature on CsA, with specific interest in studies carried out in cats. For its licensed indication, chronic allergic dermatitis, evidence provided includes randomised, placebo or prednisolone-controlled studies (EBM grade I) and prospective or retrospective open trials.

Gender aspects in allergies of pets - A secondary publication and update

Allergies need not only affect humans; this multifactorial and complex disease can also affect animals. Comparative allergology investigates the many similarities between the pathogenesis, clinics, diagnosis, and therapy of the disorders in humans and pet animals. In contrast to human allergy research, the veterinary field lacks access to a central database, which means there are no cohort studies published. This limits not only the research on breed and regional differences in allergies, but also further studies on the impact of gender in allergies of domestic animals. Moreover, domestic cats, dogs and male horses are castrated in most cases, which neutralises any effects of sexual hormones. In this review article a few interesting findings regarding gender aspects in companion animals were extracted from current literature. In summary, there is a lack of data on gender effects on allergies in cats, dogs or horses.

Comparing immediate-type food allergy in humans and companion animals-revealing unmet needs

Adverse food reactions occur in human as well as veterinary patients. Systematic comparison may lead to improved recommendations for prevention and treatment in both. In this position paper, we summarize the current knowledge on immediate-type food allergy vs other food adverse reactions in companion animals, and compare this to the human situation. While the prevalence of food allergy in humans has been well studied for some allergens, this remains to be investigated for animal patients, where owner-reported as well as veterinarian-diagnosed food adverse reactions are on the increase. The characteristics of the disease in humans vs dogs, cats, and horses are most often caused by similar, but sometimes species-dependent different pathophysiological mechanisms, prompting the specific clinical symptoms, diagnoses, and treatments. Furthermore, little is known about the allergen molecules causative for type I food allergy in animals, which, like in human patients, could represent predictive biomarkers for risk evaluation. The definite diagnosis of food allergy relies-as in humans-on elimination diet and provocation tests. Besides allergen avoidance in daily practice, novel treatment options and tolerization strategies are underway. Taken together, numerous knowledge gaps were identified in veterinary food allergy, which need to be filled by systematic comparative studies.

Skin as a marker of general feline health: Cutaneous manifestations of systemic disease

Practical relevance: Although most skin lesions occur due to diseases primarily affecting the skin, some reflect important systemic diseases. Such lesions may relate directly to the systemic disease, or may occur due to secondary skin diseases that develop because of immunosuppression. Early recognition of skin changes as a marker of systemic disease will maximise patient outcomes. Clinical challenges: In older or clearly debilitated cats presenting with skin disease, the potential for underlying systemic disease is often readily apparent. Similarly, cats presenting with severe ulcerative or multifocal nodular skin lesions, or with concurrent signs of systemic illness, will more instinctively prompt systemic evaluation. More challenging is the cat presenting with alopecic, scaling, erythemic and/or mildly crusted skin disease, with or without pruritus; hypersensitivities and infectious dermatoses are the most common considerations, but occasionally systemic disease underlies the skin changes. Knowing when screening laboratory testing, body imaging or other systemic diagnostics are indicated is not always straightforward. Evidence base: This article reviews cutaneous presentations of systemic diseases reported in the veterinary literature, and discusses important differential diagnoses. The author draws on clinical experience, published data on disease prevalence and case evaluations, and expert opinions on approach to common systemic problems to provide guidance on when investigation for underlying systemic disease is most appropriate.

Critically appraised topic on adverse food reactions of companion animals (3): prevalence of cutaneous adverse food reactions in dogs and cats

BACKGROUND

The prevalence of cutaneous adverse food reactions (CAFRs) in dogs and cats is not precisely known. This imprecision is likely due to the various populations that had been studied. Our objectives were to systematically review the literature to determine the prevalence of CAFRs among dogs and cats with pruritus and skin diseases.

RESULTS

We searched two databases for pertinent references on August 18, 2016. Among 490 and 220 articles respectively found in the Web of Science (Science Citation Index Expanded) and CAB Abstract databases, we selected 22 and nine articles that reported data usable for CAFR prevalence determination in dogs and cats, respectively. The prevalence of CAFR in dogs and cats was found to vary depending upon the type of diagnoses made. Among dogs presented to their veterinarian for any diagnosis, the prevalence was 1 to 2% and among those with skin diseases, it ranged between 0 and 24%. The range of CAFR prevalence was similar in dogs with pruritus (9 to 40%), those with any type of allergic skin disease (8 to 62%) and in dogs diagnosed with atopic dermatitis (9 to 50%). In cats presented to a university hospital, the prevalence of CAFR was less than 1% (0.2%), while it was fairly homogeneous in cats with skin diseases (range: 3 to 6%), but higher in cats with pruritus (12 to 21%) than in cats with allergic skin disease (5 to 13%).

CONCLUSIONS

Among dogs and cats with pruritus and those suspected of allergic skin disease, the prevalence of CAFR is high enough to justify this syndrome to be ruled-out with a restriction (elimination)-provocation dietary trial. This must especially be considered in companion animals with nonseasonal pruritus or signs of allergic dermatitis.

Cats are not small dogs: is there an immunological explanation for why cats are less affected by arthropod-borne disease than dogs?

It is widely recognized that cats appear to be less frequently affected by arthropod-borne infectious diseases than dogs and share fewer zoonotic pathogens with man. This impression is supported by the relative lack of scientific publications related to feline vector-borne infections. This review explores the possible reasons for the difference between the two most common small companion animal species, including the hypothesis that cats might have a genetically-determined immunological resistance to arthropod vectors or the microparasites they transmit. A number of simple possibilities might account for the lower prevalence of these diseases in cats, including factors related to the lifestyle and behaviour of the cat, lesser spend on preventative healthcare for cats and reduced opportunities for research funding for these animals. The dog and cat have substantially similar immune system components, but differences in immune function might in part account for the markedly distinct prevalence and clinicopathological appearance of autoimmune, allergic, idiopathic inflammatory, immunodeficiency, neoplastic and infectious diseases in the two species. Cats have greater genetic diversity than dogs with much lower linkage disequilibrium in feline compared with canine breed groups. Immune function is intrinsically related to the nature of the intestinal microbiome and subtle differences between the canine and feline microbial populations might also impact on immune function and disease resistance. The reasons for the apparent lesser susceptibility of cats to arthropod-borne infectious diseases are likely to be complex, but warrant further investigation.

Pollen Allergies in Humans and their Dogs, Cats and Horses: Differences and Similarities

Both humans and their most important domestic animals harbor IgE and a similar IgE receptor repertoire and expression pattern. The same cell types are also involved in the triggering or regulation of allergies, such as mast cells, eosinophils or T-regulatory cells. Translational clinical studies in domestic animals could therefore help cure animal allergies and at the same time gather knowledge relevant to human patients. Dogs, cats and horses may spontaneously and to different extents develop immediate type symptoms to pollen allergens. The skin, nasal and bronchial reactions, as well as chronic skin lesions due to pollen are in principle comparable to human patients. Pollen of various species most often causes allergic rhinitis in human patients, whereas in dogs it elicits predominantly eczematous lesions (canine atopic dermatitis), in horses recurrent airway obstruction or hives as well as pruritic dermatitis, and in cats bronchial asthma and so-called cutaneous reactive patterns (eosinophilic granuloma complex, head and neck pruritus, symmetric self-induced alopecia). In human allergy-specific IgE detection, skin tests or other allergen provocation tests should be completed. In contrast, in animals IgE and dermal tests are regarded as equally important and may even replace each other. However, for practical and economic reasons intradermal tests are most commonly performed in a specialized practice. As in humans, in dogs, cats and horses allergen immunotherapy leads to significant improvement of the clinical symptoms. The collected evidence suggests that canines, felines and equines, with their spontaneous allergies, are attractive model patients for translational studies.

Comparative immunology of allergic responses

Allergic responses occur in humans, rodents, non-human primates, avian species, and all of the domestic animals. These responses are mediated by immunoglobulin E (IgE) antibodies that bind to mast cells and cause release/synthesis of potent mediators. Clinical syndromes include naturally occurring asthma in humans and cats; atopic dermatitis in humans, dogs, horses, and several other species; food allergies; and anaphylactic shock. Experimental induction of asthma in mice, rats, monkeys, sheep, and cats has helped to reveal mechanisms of pathogenesis of asthma in humans. All of these species share the ability to develop a rapid and often fatal response to systemic administration of an allergen--anaphylactic shock. Genetic predisposition to development of allergic disease (atopy) has been demonstrated in humans, dogs, and horses. Application of mouse models of IgE-mediated allergic asthma has provided evidence for a role of air pollutants (ozone, diesel exhaust, environmental tobacco smoke) in enhanced sensitization to allergens.