A Pilot Randomized Trial to Compare Polyuria and Polydipsia during a Short Course of Prednisolone or Methylprednisolone in Dogs with Atopic Dermatitis

Simple Summary Glucocorticoids (a.k.a. steroids) are often used to treat allergic skin diseases in dogs, but they commonly cause side-effects, such as increased drinking (polydipsia) and urination (polyuria). Veterinarians have long believed that the steroid methylprednisolone causes less drinking and urination than prednisolone. We performed a clinical trial in which dogs with atopic dermatitis were treated either with prednisolone or methylprednisolone at the beginning of an elimination diet. After two weeks, the owners did not notice any significant increase in drinking. Most dogs had a reduction in the specific gravity (that is the density) of the urine, which signals a more diluted and abundant urine, but there was no significant difference between the two steroids for urine dilution. In conclusion, there were no significant changes in either drinking and urine dilution when giving prednisolone or methylprednisolone to allergic dogs for two weeks. A longer treatment duration or higher doses might give different results, however. Glucocorticoids are widely used to treat canine allergic disorders, but they frequently cause polyuria and polydipsia (PUPD). At equipotent dosages, oral methylprednisolone is believed to cause less PUPD than prednisolone. We performed a pilot randomized, open, parallel trial with 22 dogs with nonseasonal AD receiving either prednisolone or methylprednisolone at equipotent dosages, once daily for 14 days during the first phase of a restriction-provocation dietary trial. Before and on days 3, 7, and 14 after starting the glucocorticoids, owners estimated water consumption for 24 h. On the same days and before the glucocorticoid was given, owners collected the first-morning urine to determine the urine specific gravity (USG). There were no significant differences between the prednisolone and methylprednisolone groups on days 3, 7, and 14 when comparing the changes in water intake from baseline. Most dogs from both groups exhibited a slight reduction in USG during the study. Still, there was no significant difference in USG changes between the groups on any of these three reevaluation days. In conclusion, the administration of two weeks of oral prednisolone and methylprednisolone at equipotent anti-inflammatory dosages at the beginning of an elimination diet did not lead to significant differences in water intake and USG

An international seroprevalence survey of the IgE sensitisation to the Dermatophagoides farinae house dust mite and two of its major allergens (Der f 2, Zen 1) in atopic dogs

Background: Dogs with atopic dermatitis are often immunoglobulin (Ig)E-sensitised to Dermatophagoides farinae (Df) house dust mites, yet limited data exist on the sensitisation rates to the individual Df allergens, Der f 2 and Zen 1. Objectives: To determine the IgE sensitisation rates to Df, Der f 2 and Zen 1 in atopic dogs from geographically diverse countries. Animals: Serum was collected from 32 laboratory dogs in Japan, and 837 atopic dogs from 11 countries from five continents: Asia (Japan, Thailand, Taiwan), Europe (Italy, Latvia, the Netherlands, UK), North America (USA), South America (Argentina, Brazil) and Africa (South Africa). Methods and materials: We determined Df-, Der f 2- and Zen 1-specific IgE levels by ELISA. Correlations between the IgE values for these three allergens were calculated. Results: The IgE seropositivity rates for Df varied between 74% (Argentina) and 100% (the Netherlands, Thailand, South Africa), those for Der f 2 between 12% (Argentina) and 88% (South Africa), and for Zen 1 between 70% (Argentina) and 100% (the Netherlands). Apart from the especially low seropositivity rate for Der f 2-specific IgE in Argentina, the percentage of IgE sensitisation varied little between countries. There was significant correlation between the IgE levels to these three allergens which was highest between Df and Zen 1, and lowest between Zen 1 and Der f 2. Conclusions and clinical relevance: The IgE sensitisation to Df is geographically widespread. Der f 2 and Zen 1 are major allergens for dogs in almost all countries where this was evaluated

Critically appraised topic on adverse food reactions of companion animals (2): common food allergen sources in dogs and cats

Background: To diagnose cutaneous adverse food reactions (CAFRs) in dogs and cats, dietary restriction-provocation trials are performed. Knowing the most common offending food allergens for these species would help determining the order of food challenges to optimize the time to diagnosis. Results: The search for, and review and analysis of the best evidence available as of January 16, 2015 suggests that the most likely food allergens contributing to canine CAFRs are beef, dairy products, chicken, and wheat. The most common food allergens in cats are beef, fish and chicken. Conclusions: In dogs and cats, after a period of dietary restriction leading to the complete remission of clinical signs, food challenges to diagnose CAFR should begin with beef and dairy products, the most commonly recognized food allergens in these two species

Critically appraised topic on adverse food reactions of companion animals (2): common food allergen sources in dogs and cats

Background: To diagnose cutaneous adverse food reactions (CAFRs) in dogs and cats, dietary restriction-provocation trials are performed. Knowing the most common offending food allergens for these species would help determining the order of food challenges to optimize the time to diagnosis. Results: The search for, and review and analysis of the best evidence available as of January 16, 2015 suggests that the most likely food allergens contributing to canine CAFRs are beef, dairy products, chicken, and wheat. The most common food allergens in cats are beef, fish and chicken. Conclusions: In dogs and cats, after a period of dietary restriction leading to the complete remission of clinical signs, food challenges to diagnose CAFR should begin with beef and dairy products, the most commonly recognized food allergens in these two species

Skimager for the objective erythema estimation in atopic dogs

In this study, the severity of canine skin erythema was assessed objectively for the first time. Atopic dermatitis (AD) is a common canine inflammatory and pruritic skin disease associated with an allergic reaction to exogenous allergens. The monitoring of skin erythema over time with lesion severity scales like the CADESI-4 is an essential diagnostic and research tool, especially for clinical trials. Currently, the erythema assessment is subjective due to visual estimation. In our study, we calculated the erythema index (EI) in 14 atopic dogs based on the analysis of multispectral skin images taken with the Skimager device. The relationship between the EI and a visual erythema estimation was modeled by linear regression with the first-order polynomial. The coefficient of determination (r squared) reached 0.81. Based on such high correlation, we conclude that optical measurements could replace the visual estimation of erythema in atopic dogs and, thus, improve the validity of skin lesion severity scales in dogs

Critically appraised topic on adverse food reactions of companion animals (4): can we diagnose adverse food reactions in dogs and cats with in vivo or in vitro tests?

Background: The gold standard to diagnose adverse food reactions (AFRs) in the dog and cat is currently an elimination diet with subsequent provocation trials. However, those trials are inconvenient and client compliance can be low. Our objective was to systematically review the literature to evaluate in vivo and in vitro tests used to diagnose AFR in small animals. Results: We searched three databases (CAB Abstracts, MEDLINE and Web of Science) for pertinent references on September 16, 2016. Among 71, 544 and 41 articles found in the CAB Abstract, MEDLINE and Web of Science databases, respectively, we selected 22 articles and abstracts from conference proceedings that reported data usable for evaluation of tests for AFR. Serum tests for food-specific IgE and IgG, intradermal testing with food antigens, lymphocyte proliferation tests, fecal food-specific IgE, patch, gastroscopic, and colonoscopic testing were evaluated. Conclusions: Testing for serum food-specific IgE and IgG showed low repeatability and, in dogs, a highly variable accuracy. In cats, the accuracy of testing for food-specific IgE was low. Lymphocyte proliferation tests were more frequently positive and more accurate in animals with AFR, but, as they are more difficult to perform, they remain currently a research tool. All other reported tests were only evaluated by individual studies with small numbers of animals. Negative patch test reactions have a very high negative predictability in dogs and could enable a choice of ingredients for the elimination diet in selected patients. Gastroscopic and colonoscopic testing as well as food-specific fecal IgE or food-specific serum IgG measurements appear less useful. Currently, the best diagnostic procedure to identify AFRs in small animals remains an elimination diet with subsequent provocation trials

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

Critically appraised topic on adverse food reactions of companion animals (6): prevalence of noncutaneous manifestations of adverse food reactions in dogs and cats

Background: Many reports describe the cutaneous signs of adverse food reactions (AFR) in the dog and cat. However, various non-cutaneous clinical signs are less well described. Our objective was to systematically evaluate these non-cutaneous signs of AFR in small animals.Results: We searched two databases (MEDLINE and Web of Science) for pertinent references on non-cutaneous signs of adverse food reactions. Among 117 and 764 articles found in the MEDLINE and Web of Science databases, respectively, we selected 47 articles that reported data related to non-cutaneous clinical signs of AFR. Gastrointestinal signs, symmetrical lupoid onychitis, conjunctivitis, sneezing, and anaphylaxis were reported to be associated with AFR in dogs and gastrointestinal and respiratory signs, conjunctivitis, and hyperactive behaviour in cats. In Border terriers with paroxysmal gluten-sensitive dyskinesia, an underlying AFR should be considered. Of these clinical signs diarrhoea and frequent defecation were most frequently reported to be diet-responsive in dogs;in the cat, these were vomiting and diarrhoea.Conclusion: sAn elimination diet should be considered early in the work-up of dogs and cats with chronic vomiting and diarrhoea. Other non-cutaneous signs occur less commonly because of AFRs

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