Treatment of the feline atopic syndrome - a systematic review

Ciclosporin oral solution in cats: a retrospective survey of compliance with treatment and adverse effects

OBJECTIVES

The aim of the study was to assess long-term ciclosporin oral solution compliance in cats treated for feline atopic skin syndrome (FASS).

METHODS

A survey was sent by email to 114 owners who had administered ciclosporin oral solution to their cats for FASS.

RESULTS

In total, 42 owners completed the survey. The population was composed of 30 domestic shorthair cats and 12 pure breeds. There were 20 males and 22 females, and the median age was 5.5 years. Ciclosporin oral solution was administered directly into the mouth in 32/42 (76%) and with food/other in 10/42 (24%) cats. The administration was considered easy in 18/42 (43%) cats, difficult in 23/42 (55%) and impossible in 1/42 (2%). Treatment was stopped in 25/42 (60%) cats. The causes were as follows: administration difficulty (nine cats, 21%); complete resolution (four cats, 10%); treatment failure (four cats, 10%); price (two cats, 4%); and other causes (two deaths, two neoplasia, one adverse effect and one lack of compliance). Adverse effects involving clinical signs were reported in 25 (60%) cats: ptyalism (8/42); dysorexia/anorexia (6/42); vomiting (4/42); diarrhoea (4/42); gingival hyperplasia (1/42); and a combination of vomiting, diarrhoea and ptyalism (2/42). In addition, altered behaviour was reported in 27/42 (64%) cats: hiding in seven cats; scared of owner in 10 cats; modification of sleeping or playing activity in six cats; inappropriate urination/defecation in two cats; aggression in one cat; and all of the above in one cat.

CONCLUSIONS AND RELEVANCE

In total, 24 (57%) cats had adverse effects involving both clinical signs and altered behaviour, and only six cats had either adverse clinical signs or behavioural changes. This survey showed that behavioural changes appear to be underestimated in the cats treated with ciclosporin oral solution and this could cause treatment failure due to lack of compliance. Larger-scale studies are needed to confirm these preliminary results.

Reactions to environmental allergens in cats with feline lower airway disease

Objectives

Aeroallergens have been discussed as potential triggers for feline asthma (FA), which can be induced experimentally by allergen sensitization. To date, only few studies have investigated reactions to environmental allergens in cats with naturally occurring feline lower airway disease (FLAD). The aim of the study was to compare results of intradermal testing (IDT) and serum allergen-specific immunoglobulin E-(IgE) testing (SAT) in cats with FLAD, and to investigate possible associations with allergen exposure.

Material and methods

Eight cats with eosinophilic airway inflammation (EI), ten cats with mixed inflammation (MI), six with neutrophilic inflammation (NI), and 24 healthy cats (HC) were included. Cats diagnosed with FLAD were assigned to the different inflammatory groups based on bronchoalveolar lavage fluid (BLAF) cytology. SAT was performed in all cats; IDT was only carried out in cats with FLAD. Information about the cats' environment and potential allergen exposure was obtained using an owner questionnaire.

Results

In comparison to 83% of HC with positive reactions on SAT only 52% of cats with FLAD had positive responses (p = 0.051). Significantly more positive reactions per cat were detected on IDT than on SAT (p = 0.001). No significant difference was found for positive reactions per cat on SAT when compared between HC, NI, EI, and MI (p = 0.377). Only "slight" agreement was found for most allergens when reactions obtained in both tests in cats with FLAD were compared, except for "moderate" agreement for English plantain (k = 0.504) and Alternaria alternata (k = 0.488). Overall, no clear association between the cats' environment and allergen reactions were detected.

Conclusions and clinical importance

Interpretation of allergy test results in cats with FLAD should be done in the context of clinical signs and individual factors.

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.

Efficacy and Safety of Subcutaneous Allergen-Specific Immuno-Therapy in Horses with Allergic Cutaneous and Respiratory Diseases-A Systematic Review

Allergen-specific immunotherapy (AIT) is the only current intervention that has the ability to modify the immune response toward a tolerogenic state. This study aimed to assess the efficacy and safety of AIT in horses with allergic diseases in a systematic manner. Three databases were searched to identify articles reporting clinical outcomes and adverse events associated with AIT. The articles were evaluated for beneficial responses to AIT, defined as a ≥50% reduction in clinical signs, and clinical remission. Horses with respiratory diseases, urticaria, and pruritic dermatitis receiving insect monotherapy or multi-allergen AIT were included. All adverse events were graded, and analytical and confounding biases were assessed. The results showed that multi-allergen AIT had a beneficial response in 75% of horses with respiratory diseases, 88% with urticaria, and 56% with pruritic dermatitis. However, horses treated solely with insect AIT for pruritic dermatitis had a lower response rate (36%). Self-limiting local reactions were the most common adverse events, with systemic reactions grade II accounting for 11% of reported events. Analytical and confounding biases were identified as major limitations in the available studies. Further research is needed to address these biases and provide stronger evidence on the efficacy and safety of AIT in horses with allergic diseases.

Sphingomyelin-Rich Lipid Extract Collar for Canine Atopic Dermatitis

The management of canine atopic dermatitis (CAD) is complex, and it needs to be multimodal, combining topical and systemic therapies. Given that the currently available options are not always totally effective and might have some associated adverse effects, novel alternatives are needed. For this reason, a new collar for CAD was developed with 2.5% of a sphingomyelin-rich lipid extract (LE) with proven benefits for skin health. The release of the active ingredient when incorporated into the collar was tested in vitro, showing an adequate kinetic profile. Then, the efficacy and safety of the collar were assessed in 12 client-owned dogs with CAD in a pilot study. After eight weeks, the dogs experienced significant clinical improvements on the Canine Atopic Dermatitis Extent and Severity Index (CADESI)-4, Pruritus Index for Canine Atopic Dermatitis (PCAD) and Pruritus Visual Analogue Scale (PVAS) scores, without any adverse effects. Additionally, further in vitro studies were performed, indicating that this LE collar should be compatible with antiparasitic collars (with deltamethrin or imidacloprid/flumethrin) if worn simultaneously. Given the observed benefits of this LE collar, combining it with other CAD therapies could potentially allow for drug sparing, reduction in adverse effects, enhanced owner compliance, and reduced treatment costs.

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.

Interobserver reliability of Feline Dermatitis Extent and Severity Index (FEDESI) and Scoring Feline Allergic Dermatitis (SCORFAD) and the relationship between lesion scores and pruritus

BACKGROUND

Feline Dermatitis Extent and Severity Index (FEDESI) and Scoring Feline Allergic Dermatitis (SCORFAD) are scales used to assess lesion severity in cats with allergic dermatitis. Interobserver reliability has not been assessed for either.

HYPOTHESIS AND OBJECTIVES

To determine interobserver reliability for FEDESI and SCORFAD, and the relationship between lesion scores and pruritus.

ANIMALS

Thirty-eight cats presenting for pruritus.

METHODS AND MATERIALS

Each cat's lesions were scored by two observers at each visit using both FEDESI and SCORFAD (n = 117 paired observations). Spearman's rho was calculated to assess correlation between scales and between each scale and the owner-reported pruritus Visual Analog Scale (pVAS). Concordance correlation coefficients were calculated between observers for each scale, and Bland-Altman plots were used to visually represent the relationship between paired scores.

RESULTS

FEDESI and SCORFAD were strongly positively correlated with one another (rho = 0.84, P < 0.001). Each scale showed fair correlation with pVAS (rho = 0.42, P < 0.001; rho = 0.38, P < 0.001, respectively). There was good concordance between observers for both scales, with a correlation coefficient of 0.77 for FEDESI and 0.80 for SCORFAD [intraclass correlation coefficient (ICC) 95%, confidence interval (CI) 0.69-0.83; ICC 95%, CI 0.72-0.86, respectively]. Median lesion score was low (FEDESI 20; SCORFAD 4), which may improve interobserver reliability.

CONCLUSIONS AND CLINICAL IMPORTANCE

There is good interobserver reliability for both FEDESI and SCORFAD. FEDESI and SCORFAD are positively correlated with one another and with pVAS. These findings support use of both scales in clinical research and assessment.

Atopic Dermatitis in Domestic Animals: What Our Current Understanding Is and How This Applies to Clinical Practice

Atopic dermatitis is a clinical syndrome that affects both people and animals. Dogs closely mimic the complexity of the human skin disease, and much progress has been made in recent years in terms of our understanding of the role of skin impairment and the identification of new treatments. Cats and horses also develop atopic syndromes which include both cutaneous and respiratory signs, yet studies in these species are lagging. It is now recognized that atopic dermatitis is not a single disease but a multifaceted clinical syndrome with different pathways in various subgroups of patients. Appreciating this complexity is clinically relevant as we develop more targeted treatments which may work well in some patients but not in others. Different phenotypes of atopic dermatitis have been described in dogs, and it is possible that phenotypes related to breed and age may exist in other animals similar to how they are described in people. The awareness of different mechanisms of disease leads to the desire to correlate different phenotypes with specific biomarkers and responses to treatment. In this review, the current understanding and updated information on atopic syndrome in animals are described, highlighting opportunities for further studies in the future.

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.

Intradermal immunotherapy with actinomycetales preparations as treatment for feline atopic syndrome: a randomized, placebo-controlled, double-blinded study

BACKGROUND

Feline atopic syndrome (FAS) is a common disease. Single intradermal injections of heat-killed actinomycetales have shown beneficial effects in canine allergies.

HYPOTHESIS/OBJECTIVE

To evaluate the clinical effects of heat-killed actinomycetales [Gordonia bronchialis (GB) and Rodococcus coprophilus (RC)], alone or in combination, in FAS.

METHODS AND MATERIALS

Privately owned cats with a diagnosis of FAS were assigned randomly in three treatment groups (GB, RC and GB/RC combination) or placebo. Five intradermal injections were performed over a one year period. At each visit [Day (D)0, D20, D40, D60, D90, D180 and D365], clinical signs, global owner assessment score, use of rescue medications, clinical adverse effects, skin hydration and cutaneous pH were assessed.

RESULTS

Seventeen cats were enrolled. When compared to the placebo group and improvement in treatment GB was sustained from D90. When compared with D0 significant improvement in the GB group was seen from D60. Over one year, a complete remission of the clinical signs was seen in 30-67% of cats in the treatment groups. A reduction in the pruritus score was seen for RC after 365 days of treatment (P = 0.04). Differences in the other variables were not seen.

CONCLUSIONS AND CLINICAL IMPORTANCE

The use of multiple intradermal injections of heat-killed GB shows promise as effective and well-tolerated treatment for FAS. Because of the low cost and the lack of adverse effects, GB could be a beneficial treatment option for FAS. A larger study is needed to confirm these data and to evaluate the immunological changes occurring in the treated cats.