Could we use the erythema grading of the CADESI4 as a simple instrument for future short-duration clinical trials of dogs with atopic dermatitis?

Establishment of clinical criteria for the diagnosis of adverse food reactions in dogs with atopic dermatitis

BACKGROUND

Diagnosis of canine adverse food reactions (AFRs) is based on vague criteria, such as '>50% improvement' during elimination diet trial (EDT) followed by 'deterioration' during provocation test (PT).

OBJECTIVE

The objective of the study was to use predefined criteria to evaluate response during EDT [i.e., Owner Global Assessment of Treatment Efficacy (OGATE) = good-to-excellent] and relapse during PT [i.e., Owner Global Assessment of Challenge Deterioration (OGACD) = moderate-to-severe and/or >100% increase of lesional (Canine Atopic Dermatitis Extent and Severity Index, 4th iteration, CADESI-04) and/or of pruritus (pruritus Visual Analog Scale, PVAS) scores].

ANIMALS

Twenty-nine dogs with atopic dermatitis.

MATERIALS AND METHODS

An extensively hydrolysed diet was fed to all dogs followed, in seven of 11 nonresponders, by a second home-made novel-protein EDT. Dogs responding to either EDT were challenged with their previous diet.

RESULTS

Thirteen (44.8%) dogs were diagnosed with AFRs: at the end of EDT, their OGATE was good (9 of 13; 69.2%) or excellent (four of 13; 30.8%), and both CADESI-04 (46.7%) and PVAS (71.1%) had decreased significantly; at the end of PT, OGACD was moderate or severe in 12 of 13 (92.3%) dogs, and both CADESI-04 (127.9%) and PVAS (181.8%) had increased significantly. Of the 16 dogs without AFRs, 6 (37.5%) responded to the commercial (n = 5) or home-made (n = 1) diet [OGATE = good (three of six) or excellent (three of six)], with significant concurrent reduction of CADESI-04 and nonsignificant reduction of PVAS, yet they did not relapse during PT.

CONCLUSIONS AND CLINICAL RELEVANCE

The proposed (predefined) criteria for the evaluation of response during EDT and deterioration during PT seem reliable and are easily applicable in clinical practice and research.

A randomised controlled trial testing the rebound-preventing benefit of four days of prednisolone during the induction of oclacitinib therapy in dogs with atopic dermatitis

BACKGROUND

A rebound of pruritus occasionally occurs after oclacitinib dose reduction in dogs with atopic dermatitis (AD).

OBJECTIVES

To determine whether an initial 4-day course of prednisolone decreases the probability of a pruritus rebound after reducing the frequency of oclacitinib administration.

ANIMALS

Forty dogs with mild-to-moderate AD lesions and moderate-to-severe pruritus.

MATERIALS AND METHODS

Dogs were randomised to receive oclacitinib at 0.4-0.6 mg/kg twice daily for 14 days then once daily, alone or with prednisolone at 0.5 mg/kg, orally, twice daily for the first 4 days. Clinicians graded the Canine Atopic Dermatitis Extent and Severity Index (CADESI)4 and 2D-investigator global assessment (IGA) before and after 28 days; owners assessed the pruritis Visual Analog Scale (PVAS)10 and Owner Global Assessment of Treatment Efficacy (OGATE) on Day (D)0, D4, D14, D21 and D28. We considered a rebound any increase greater than one PVAS10 grade at D21 compared to D14.

RESULTS

On D21, there were significantly fewer rebounds in the dogs receiving prednisolone (three of 20, 15%) compared to those given oclacitinib alone (nine of 20, 45%; Fisher's test, p = 0.041). Compared to oclacitinib monotherapy, the concurrent administration of prednisolone for the first 4 days led to significantly lower PVAS10 on D4 and D28, CADESI4 and 2D-IGA on D28, and OGATE on D21 and D28 (Wilcoxon-Mann-Whitney U-tests). Adverse effects of therapy were minor, intermittent and self-resolving.

CONCLUSIONS AND CLINICAL RELEVANCE

The initial addition of 4 days of prednisolone significantly decreased the probability of a rebound of pruritus 1 week after oclacitinib dose reduction. This short concomitant glucocorticoid administration led to a higher skin lesion improvement and improved perception of treatment efficacy with minimal adverse effects.

Efficacy of Antimicrobial Treatment in Dogs with Atopic Dermatitis: An Observational Study

There is a shortage of studies reporting the efficacy of antimicrobial treatment of dogs with atopic dermatitis (AD) and skin infections (SIs). The aim of this study was to evaluate the change in the severity of skin lesions and pruritus, and the overall efficacy of antimicrobial treatment, in dogs with AD and bacterial overgrowth/infection and/or Malassezia dermatitis. A total of 20 dogs with AD and SIs were prospectively enrolled (group A) and they were examined before and after the administration of systemic antimicrobials that resulted in the resolution of SIs. In addition, 19 dogs fulfilling the same inclusion criteria and treated with systemic, with or without topical antimicrobials, were included retrospectively (group B). Since there were no major differences between the groups, their results were combined. The severity of skin lesions decreased significantly, by 30% based on Canine Atopic Dermatitis Extent and Severity Index-4 (CADESI-4), by 28.1% based on the erythema domain of CADESI-4 and based on owner’s global assessment of the severity of skin lesions. Pruritus decreased significantly, by 34.7% based on the Pruritus Visual Analogue Scale (PVAS). The efficacy of antimicrobial treatment was assessed as good to excellent by the investigator and the owner in 55% and 60% of the dogs, respectively. Despite the significant improvement, there was high variability in the response to treatment among dogs. Further studies are needed to find factors that determine the response to antimicrobial treatment in dogs with AD and SIs.

The effect of a mixed cannabidiol and cannabidiolic acid based oil on client‐owned dogs with atopic dermatitis

Background

Cannabidiol (CBD) and cannabidiolic acid (CBDA) are reported to have antinociceptive, immunomodulatory and anti‐inflammatory actions.

Objectives

To determine if CBD/CBDA is an effective therapy for canine atopic dermatitis (cAD).

Animals

Thirty‐two privately owned dogs with cAD.

Materials and methods

Prospective, randomised, double‐blinded, placebo‐controlled study. Concurrent therapies were allowed if remained unchanged. Dogs were randomly assigned to receive either 2 mg/kg of an equal mix of CBD/CBDA (n = 17) or placebo for 4 weeks. On Day (D)0, D14 and D28, Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI‐04) and pruritus Visual Analog Scale (pVAS) scores were determined by investigators and owners, respectively. Complete blood count, serum biochemistry profiles and cytokine bioassays were performed on serum collected on D0 and D28.

Results

There was no significant difference in CADESI‐04 from D0 to D14 (p  = 0.42) or D28 (p  = 0.51) in either group. pVAS scores were significantly lower for the treatment group at D14 (p  = 0.04) and D28 (p  = 0.01) and a significant change in pVAS from baseline was seen at D14 (p  = 0.04) and not D28 (p  = 0.054) between groups. There was no significant difference in serum levels of interleukin (IL)‐6, IL‐8, monocyte chemoattractant protein ‐ 1, IL‐31 or IL‐34 between groups at D0 or D28. Elevated alkaline phosphatase was observed in four of 17 treatment group dogs.

Conclusions and clinical relevance

CBD/CBDA as an adjunct therapy decreased pruritus, and not skin lesions associated with cAD in dogs.

Evaluation of Erythema Severity in Dermatoscopic Images of Canine Skin: Erythema Index Assessment and Image Sampling Reliability

The regular monitoring of erythema, one of the most important skin lesions in atopic (allergic) dogs, is essential for successful anti-allergic therapy. The smartphone-based dermatoscopy enables a convenient way to acquire quality images of erythematous skin. However, the image sampling to evaluate erythema severity is still done manually, introducing result variability. In this study, we investigated the correlation between the most popular erythema indices (EIs) and dermatologists’ erythema perception, and we measured intra- and inter-rater variability of the currently-used manual image-sampling methods (ISMs). We showed that the EI_BRG, based on all three RGB (red, green, and blue) channels, performed the best with an average Spearman coefficient of 0.75 and a typical absolute disagreement of less than 14% with the erythema assessed by clinicians. On the other hand, two image-sampling methods, based on either selecting specific pixels or small skin areas, performed similarly well. They achieved high intra- and inter-rater reliability with the intraclass correlation coefficient (ICC) and Krippendorff’s alpha well above 0.90. These results indicated that smartphone-based dermatoscopy could be a convenient and precise way to evaluate skin erythema severity. However, better outlined, or even automated ISMs, are likely to improve the intra- and inter-rater reliability in severe erythematous cases.

Evaluation of skin erythema severity by dermatoscopy in dogs with atopic dermatitis

BACKGROUND

To estimate the extent and severity of atopic dermatitis (AD)-related skin lesions, clinical trials enrolling dogs with AD often use categorical scales such as the Canine Atopic Dermatitis Extent and Severity Index, 4^th iteration (CADESI-04) and Canine Atopic Dermatitis Lesion Index (CADLI). Despite recent progress in the standardization of these AD-grading scales, the evaluation of the severity of skin lesions (including erythema) remains subjective.

OBJECTIVES

To validate an optical set-up with a smartphone and a dermatoscope for the objective estimation of skin erythema severity in atopic dogs.

ANIMALS

Forty-three dogs with AD.

METHODS AND MATERIALS

An erythema index (EI) was calculated from calibrated skin images and compared to the dermatologist's erythema severity estimate using the erythema grading scale used in the CADESI-04, as well as an ad hoc Visual Analog Scale (VAS) with a continuous palette of red shades.

RESULTS

We found a strong correlation based on the Spearman rank correlation coefficient between all erythema valuations: CADESI-04 and VAS: 0.93 [95% CI: (0.85, 0.96)]; CADESI-04 and EI: 0.85 (0.72, 0.92); VAS and EI: 0.82 (0.67, 0.91). There was a good agreement between the objective EI and CADESI-04-based estimates because 71% of samples were classified in the same erythema severity category. When comparing the EI and the VAS, the standard deviation of misestimates was 12% (maximum 100%).

CONCLUSIONS AND CLINICAL RELEVANCE

The proposed optical set-up has the potential to make erythema severity estimation objective, thus leading to more reliable AD severity scales for the use in experimental canine AD models or in clinical trials enrolling atopic dogs.