The influence of mometasone furoate ear solution on intradermal test immediate reactions in dogs with atopic dermatitis

Multivariable analysis of the influence of cross-reactive carbohydrate determinant inhibition and other factors on intradermal and serological allergen test results: a prospective, multicentre study

BACKGROUND

Serological allergen testing (SAT) is used widely to formulate allergen-specific immunotherapy for atopic dogs. Serum immunoglobulin (Ig)E specific for cross-reactive carbohydrate determinants (CCD) can produce false-positive reactions, creating discrepancy between SAT and intradermal allergen test (IDAT) results.

OBJECTIVES

The primary objective was to determine if inhibition of anti-CCD IgE in a commercial assay improved correlation with IDAT. The secondary objective was to assess the influence of dog- and clinic-specific factors, environmental factors, putative allergen exposure and prior medications on intradermal and SAT reactivity.

ANIMALS

Two-hundred and eleven client-owned dogs were enrolled from eight North American dermatology specialty practices.

METHODS AND MATERIALS

Collection of serum samples and IDAT were performed on the same day. Sera were assayed for detection of IgE specific to 25 allergens, before and after treatment with a proprietary inhibitor of anti-CCD IgE. Data for each dog were collected via a questionnaire filled out by veterinary personnel.

RESULTS

The correlation between the testing modalities was fair before (Spearman's rho, ρ = 0.2092) and after (ρ = 0.3042) inhibition of anti-CCD IgE. Ciclosporin dose (P = 0.003), independent of duration of use, and duration of lokivetmab use (P = 0.001), independent of dose administered, were associated with statistically significant decreases in IgE concentrations across all allergen types.

CONCLUSIONS AND CLINICAL RELEVANCE

Contrary to previous reports, this study demonstrated unchanged correlation between SAT and IDAT after inhibition of anti-CCD IgE. Ciclosporin dose and lokivetmab treatment duration may have unexplored effects on IgE concentration during SAT.

Preventive use of a topical anti-inflammatory glucocorticoid in atopic dogs without clinical sign of otitis does not affect ear canal microbiota and mycobiota

BACKGROUND

Otitis externa is associated with a lack of bacterial/fungal diversity in atopic dermatitis. Clinical experience has shown that use of topical corticosteroids in the ear canal (EC) can prevent otitis. No data are available on the impact of this treatment on the EC microbiota.

HYPOTHESIS/OBJECTIVES

To observe the bacterial/fungal diversity in the EC and the clinical effect of topical corticosteroids administered over a four week period in atopic dogs without active otitis.

ANIMALS

Ten atopic dogs without active otitis.

METHODS AND MATERIALS

Mometasone was applied in the right EC, while the left was used as control. A clinical and cytological evaluation of the EC was performed. Swabs of each EC were analysed using next-generation sequencing methods.

RESULTS

At the beginning of the trial, variations in microbiota and mycobiota were observed between dogs and also within individuals. Statistically, no significant difference was observed in alpha and beta diversity between the treated and the untreated group over time. Clinically, right and left EC diversities were no different at Day (D)28 (P = 0.28). A significant difference was noted between D0 and D28 for the treated ears (P = 0.012) and not for the untreated ears (P = 0.63). No cytological evidence of microbes was found for treated ECs at D28.

CONCLUSIONS AND CLINICAL RELEVANCE

These data suggest that the use of topical corticosteroids as proactive treatment is unlikely to increase the risk of secondary microbial overgrowth. The positive clinical effect of this proactive treatment seems to be supported through cytological and otoscopic improvement.

Topical ear treatment - options, indications and limitations of current therapy

Topical otic products form an integral part of the overall management of otitis externa. With an ever increasing array of ear drops and cleaners to choose from, appropriate selection of therapy can be difficult. The investigation of all cases of otitis externa should consider primary and secondary causes and predisposing and perpetuating factors. This article considers topical therapy under these same broad headings and discusses, through literature review, the various properties of the components of the ear cleaning solutions and drops.