Diagnosis Of Canine Atopic Dermatitis Research Articles

A 3-Year Case Report on an Atopic Patient with a Caninised Monoclonal Antibody Treatment

Abstract A 6-year-old, male, neutered, English Mastiff dog was presented for a second opinion due to chronic pruritus. The patient had been on methylprednisolone and chlorphenamine for four years. The diagnostic investigations included: swabs for bacterial and mycology culture, hair plugs for dermatophyte culture, acetate tape strips and deep skin scrapes, skin biopsies for dermatohistopathology, biochemistry, haematology, endocrinology, serology for canine scabies using enzyme-linked immunosorbent assay (ELISA) testing and serology for allergen specific IgE antibodies. The history and the diagnostics confirmed the diagnosis of canine atopic dermatitis. This case report details the treatment with lokivetmab, which is a caninised monoclonal antibody drug. At periods of flare ups, additional treatments were prescribed, such as systemic glucocorticoids and oclacitinib in order to manage the clinical signs. The treatment showed good response to the overall treatment management during the three year period of this atopic patient.

Case study on Canine Atopic Dermatitis from a medico-legal viewpoint: A takeaway of knowledge for practicing veterinary clinicians.

Background:Despite pets are sentient beings, they are legally considered and regulated as objects in sales contracts. Therefore, the buyer is protected by law if the purchased animal should be affected by defects such as an illness or a congenital / hereditary condition that depreciates its value. In the sale of animals, a disease is legally considered a defect if it is hidden, severe, and pre-existing at the time of purchase. Canine Atopic Dermatitis (CAD) having these three requirements can, therefore, legally be considered a defect. To acquire his legal rights, the buyer must obtain a certification from the veterinarian reporting that the animal was unfit for buying within a certain time frame.Aim:This paper analyzes the legal choices that owners of dogs affected with CAD can make to help practicing veterinary clinicians comprehend and recognize this disease and because it may be considered a defect.Methods:Thirteen cases of CAD are reported and analyzed from a medico-legal point of view.Results:In cases n. 2, 3, 4, 5, 7 owners of dogs affected with CAD partial or full reimbursement from the seller obtained. In cases n. 9, 10, 11, 12, and 13, dog owners could not take any legal action because the diagnosis of CAD was made beyond the time limits required by law. In cases n. 1, 6, and 8, the owners decided not to take any legal action.Conclusion:The veterinarian practitioner is a key professional figure not only for diagnosing the disease within the legal time limits, but also for support the owner in medico-legal disputes. A basic medico-legal background for all veterinarians and greater involvement of them in the sale of animals as a guarantee for the buyer is recommended.

Analysis of Systemic and Cutaneous Inflammatory Immune Response in Canine Atopic Dermatitis

Background: Canine atopic dermatitis (CAD) is a chronic and inflammatory disease present in veterinary dermatological practice. The inflammation in CAD is triggered by environmental allergens and skin microorganisms, which are responsible for the worsening of cutaneous lesions. This continuous activation of skin inflammatory process can induce the production of free radicals that also contribute to cellular damage and ultimately leads to changes in blood parameters in dogs with CAD. Although there are reports of inflammatory parameters in CAD, there are a lack of studies correlating skin lesions, blood leukocytes and oxidative stress. Based on that,this study aimed to evaluate the integumentary and systemic inflammatory response in dogs with atopic dermatitis. Materials, Methods & Results: Dogs with confirmed diagnosis of canine atopic dermatitis (n = 10) were divided in two groups according to CADESI-IV: AI, with CADESI between 0-10, AII, with CADESI between 10-34, and control group (n = 5). Blood-biochemical and histological analysis were performed to access systemic and cutaneous inflammatory response. AII group tended to higher neutrophil and eosinophil counts, as well as neutrophil/lymphocyte ratio (NLR) when compared to AI. The albumin was lower in AII compared to AI and control (P < 0.05), while total bilirubin and malondialdehyde (MDA) did not differ between groups. NLR (r = 0.64 and P = 0.04) and MDA (r = 0.54 and P = 0.1) were positively correlated with CADESI, while albumin was negatively correlated with CADESI (r = -0.79 and P = 0.005). Histopathological analysis revealed a larger number of neutrophils, macrophages and mast cells in AI and AII than in control group (P < 0.05). Discussion: In this study it was possible to evaluate the systemic and cutaneous leukocyte dynamics in CAD. Skin inflammation induces the production of chemotactic molecules contribute to neutrophil outflow from blood vessel toward the affected tissue, which can be visualized as perivascular inflammatory infiltrate and exocytosis. At systemic level, there was a tendency to increase in total leukocytes and circulating neutrophil count in group AII, as well as in neutrophil/lymphocyte ratio (NLR), when compared to AI. The NLR is a widely available and inexpensive laboratory biomarker that quantifies systemic inflammation, being used in human medicine to evaluate prognosis in different types of cancer. In our study, dogs in AII group showed an increased NLR compared to AI and control, which demonstrates the influence of skin injury in systemic parameters. Furthermore, AII group is composed of dogs with greater lesion state, which reflects in higher NLR values. Since this disease is known by its chronicity and may remain stable for years, NLR may be a novel biomarker to evaluate acute exacerbation in CAD and could potentially explain why some patients have longer crisis duration and frequent flares. The maintenance of the inflammatory state also induces the production of oxidizing substances, which possibly exceed the total antioxidant capacity, generating a situation of oxidative stress, which can result in damage to membrane lipids and release of their products. MDA is reliable and is the most commonly used marker of the overall lipid peroxidation level and the presence of oxidative stress. This result may be related with the antioxidant system, such as albumin and bilirubin, which was able to promote an efficient control of oxidant substances. In conclusion, the presented data demonstrated an inflammatory process progression as well as introduced NLR as a potential marker of disease exacerbation in CAD.

Diagnosis of Canine Atopic Dermatitis in Pugs by Intradermal Test

Diagnosis of Canine Atopic Dermatitis in Pugs by Intradermal Test

Reliability of different sets of criteria in diagnosing canine atopic dermatitis applied to a population of 250 dogs seen in a veterinary teaching hospital.

Different sets of criteria are available in veterinary dermatology for the diagnosis of canine atopic dermatitis (cAD); there are limited data to assess their reliability. The aim of this study was to assess the discriminative and predictive ability of four sets in diagnosing cAD in a population of dogs with different skin diseases. Two hundred and fifty dogs examined in the dermatology unit of a veterinary teaching hospital. Dogs were diagnosed with cAD, flea infestation (FI), flea bite hypersensitivity (FBH), sarcoptic mange (SM) and other skin diseases (OD). FI, FBH and SM were pooled in one group of dermatoses mimicking cAD (MD). All nonatopic dogs were grouped as a "global population" (GP). Four criteria sets were applied to all dogs. For each set of criteria, sensitivity, specificity, positive and negative predictive values (PPV, NPV), likelihood ratios (LR) and diagnostic odds ratio (DOR) were calculated. When applied to the GP, sensitivities ranged from 54 to 83%, specificities from 68 to 75% and PPVs from 35 to 43%. NPVs ranged from 87 to 94%. LRs and DORs were poor. When applied to MD, sensitivities remained unchanged, specificities and PPV were mildly higher, whereas NPVs were mildly lower and LRs and DORs were comparable. This study showed that each set of criteria had a low diagnostic reliability when used alone. The use of more discriminant criteria integrated into a thorough clinical approach excluding MDs should be considered.

Vitamin D therapy in canine atopic dermatitis

Allergic diseases are caused by an exaggerated and often deleterious response of the immune system to specific antigens.1 Canine atopic dermatitis is a genetically predisposed, inflammatory and pruritic allergic skin...

The future of immunotherapy for canine atopic dermatitis: a review.

Allergen specific immunotherapy (ASIT) is a foundation treatment for canine atopic dermatitis (CAD), though few critical studies have documented its effectiveness as a disease-modifying treatment in dogs. The mechanisms by which ASIT works in dogs have not been elucidated, although they are likely to parallel those known for humans. Current ASIT approaches in CAD focus on either subcutaneous or sublingual administration. Greater knowledge of major allergens in dogs, ideal dosage regimes and details of allergen admixture are likely to lead to better efficacy in CAD. Evaluation of biomarkers for successful therapy may also be of benefit. Potentially important advances in human medicine, that have yet to be explored in dogs, include use of modified allergen preparations such as allergoids, recombinant major allergens or allergen peptides; modification with adjuvants; or packaging of the above in virus-like particles. Co-administration of immunomodulators such as CpG oligodeoxynucleotides or specific monoclonal antibodies might direct the immune response in the desired direction while calming the "cytokine storm" of active disease. Initial trials of alternative routes of administration such as intralymphatic immunotherapy have yielded exciting results in humans, and continuing study in dogs is underway. Progress in ASIT of human food allergy may provide clues that will assist with improved diagnosis and patient management of CAD. Importantly, further study must be undertaken to clarify the conditions under which ASIT is a valuable treatment modality for dogs.

Evaluation of the Agreement between Immunodot Assays and Intradermal Skin Testing or Favrot Diagnostic Criteria in Canine Atopic Dermatitis

This study was undertaken to identify differences between atopic and non-atopic dogs in three rapid screening immunodot assays as well as the ability of the assays to predict the results of intradermal skin testing (IDST) or Favrot diagnostic criteria (FDC). Twenty-nine dogs diagnosed with canine atopic dermatitis (CAD) were selected as the atopic group. Twenty-five dogs without CAD were included as the non-atopic group. Three types of immunodot assays were conducted on all serum samples from both groups: Allercept E-screen 2nd generation (ES2G), Canine Allergic Tendency Reference Test (ALERT), and Asan Easy Test Canine IgE (AETC). IDST, which included 39 allergens, and immunodot assays were performed concurrently in 13 dogs from the atopic group and compared. While there were no significant differences in positivity between the two groups in the evaluation of ALERT (P = 0.435) and AETC (P = 0.313), positivity in ES2G testing was significantly higher in the non-atopic group than the atopic group (P = 0.038). The ES2G, ALERT, and AETC results showed fair (κ = 0.235), slight (κ = 0.133), and slight (κ = 0.014) accordance with IDST, respectively. The outcomes of ES2G, ALERT, and AETC indicated poor (κ = −0.211), slight (κ = 0.106), and slight (κ = 0.087) agreement with FDC. In conclusion, rapid screening immunodot assays were not useful for the diagnosis of CAD. These assays may provide a supplementary method for predicting the results of IDST in atopic dogs.

Prospective pilot study to detect dogs with non food‐induced canine atopic dermatitis using Fourier transform infrared spectroscopy

The diagnosis of canine atopic dermatitis (CAD) remains challenging due to the lack of a simple biomarker or metabolic profile. In human medicine, Fourier transform infrared spectroscopy (FTIR) is an analytical technique used for several diseases. It requires a small amount of sample and allows the identification of structural moieties of biomolecules on the basis of their infrared absorption, with limited sample pretreatment. The aim of the study was to evaluate the diagnostic value of FTIR. Three groups were tested: 21 dogs with non food-induced CAD (NFICAD), 16 dogs with inflammatory conditions of various origins but without allergic dermatoses (OD) and 10 healthy dogs (H). Peripheral blood was collected and spectra were acquired with a FTIR spectrophotometer. A principal component analysis (PCA) was performed on the full wavenumber spectra (4000-600/cm), followed by a Fisher discriminant analysis (DA) to assess the differences between the three groups. The PCA followed by the DA of whole spectra showed significant differences between the three groups. These results suggest that by using the FTIR method, dogs with NFICAD can be differentiated from healthy dogs and dogs with nonallergic inflammation. There was no overlap between the spectral data of the three groups indicating that NFICAD dogs were correctly segregated from the H and OD groups. A study on a larger cohort including common pruritic skin diseases is necessary to confirm these initial results and the relevance of this diagnostic technique.

Comparison of rapid screening immunoassay and intradermal test for canine atopic dermatitis

The intradermal test (IDT) has been developed for confirming diagnosis of canine atopic dermatitis (CAD). Prior to performing IDT, rapid immunoassay (Allercept E-screen 2nd generation; ES2G) can detect allergen-specific immunoglobulin E (IgE) antibodies in canine serum. The objective of this study was to evaluate agreement between IDT and immunoassay in diagnosis of CAD in domestic atopic dogs. Forty dogs were diagnosed with CAD in accordance with Favrot’s criteria. Intradermal testing was performed using 39 selected allergens. ES2G detected IgE antibodies specific for three allergen groups, including indoor allergens, grasses and weeds, and trees. Among 19 dogs diagnosed by IDT, the highest positivity was observed in house dust mites, followed by molds, epidermis and inhalants, house dust, and weeds. A total of 28 atopic dogs were evaluated by rapid ES2G immunoassay. Indoor allergens showed the strongest positive reaction, followed by grasses/weeds and trees. IDT and ES2G were performed concurrently in 17 dogs. The results of ES2G showed slight agreement with those of IDT. Level of agreement was highest for indoor allergens, which showed a predictive positive value of 100% in ES2G. These results indicate that a rapid immunoassay may be valuable for predicting the results of IDT in atopic dogs sensitized to indoor allergens.

Evaluation of criteria for diagnosis of atopic dermatitis and detection of allergen specific IgE antibodies in dogs allergic to Ambrosia artemisiifolia pollen

Common ragweed (Ambrosia atremisiifolia) is one of the most frequent causes of pollen-induced allergic reactions both in humans and dogs. It has not been defined yet, what is the major allergen(s) to which most dogs allergic to ragweed show a positive result on intradermal skin test (IDST). In the present study sensitization to Ambrosia artemisiifolia pollen allergens in dogs with atopic dermatitis was examined with both in vivo and in vitro tests, including IDST and serum allergen specific IgE test. Detection of specific-IgE antibodies against ragweed allergens by immunoblotting in the sera of allergic dogs was optimized, as well. Dogs that were positive, as judged by IDST reactions to ragweed pollen allergens, also had alergen specific IgE antibodies in their sera. Results indicate that major allergens of A. artemisifolia pollen in dogs are Amb a 1 and Amb a 2. Further characterization of ragweed allergens is needed before they could potentially be used in intradermal testing or allergen immunotherapy in affected dogs. Also, we evaluated new Favrots diagnostic criteria for canine atopic dermatitis in dogs allergic to Ambrosia atremisiifolia pollen. It might be concluded that proposed criteria are of great assistance for seting up suspected diagnosis of canine atopic dermatitis, after ruling out other pruritic dermatoses. [Projekat Ministarstva nauke Republike Srbije, br. 172024]

Characterization of pruritus in canine atopic dermatitis, flea bite hypersensitivity and flea infestation and its role in diagnosis

In dogs, flea infestation (FI), flea bite hypersensitivity (FBH) and canine atopic dermatitis (CAD) have been mainly characterized by their lesions but never by their pruritus. In clinical practice, many of these dogs exhibit only pruritus. The purpose of this study was to evaluate the characteristics of pruritus in these dermatoses and their potential usefulness for diagnosis. Dogs included were selected from the Oniris clinical data. Cases were selected in which the dogs had only one of the three dermatoses diagnosed. The diagnosis of CAD was based on Prélaud's criteria and positive intradermal tests except flea; for FBH by compatible clinical signs and a response to an intradermal test with flea allergen; and for FI by the presence of fleas. Moreover, in each group, other primary pruritic skin diseases were excluded. Location, behavioural manifestations, seasonality and quantification of the pruritus were evaluated. The statistical analysis used chi-squared test with a P-value <0.05. Three hundred and forty-six dogs were analysed, 91 with CAD, 110 FI and 145 FBH. The period (season) of onset was not statistically different either for each dermatosis or among the three dermatoses. Some locations were highly specific for one dermatosis as follows: ventral abdomen/medial surface of thigh (chewing) and radius/carpus/tibia/tarsus (chewing) in FI; back/dorsolumbar area (chewing) and tail (chewing) in FBH; and paws (chewing/licking) and face/neck (rubbing) in CAD. Some features of pruritus could be suggestive of the causal disease, with possible diagnostic value in pruritic dogs.

Canine atopic dermatitis in the Middle East: clinical signs, signalment and common allergens

&amp;nbsp; The aim of the study was to examine for the first time the various aspects of canine atopic dermatitis (CAD) presenting in a Middle Eastern country. Medical records of 164 dogs diagnosed with CAD were evaluated. Associations between signalment, lifestyle, clinical signs and allergens were evaluated statistically. Labrador Retriever, German Shepherd dog, Boxer, French Bulldog, Golden Retriever and Shar-Pei breeds were presented more frequently than the regular hospital population (P &amp;lt; 0.0001), and had an earlier disease onset time (P &amp;lt; 0.01). In 22 dogs (13%) signs of CAD were noticed at less than six months of age. Most dogs (75%) lived indoors. Most dogs (83%) had lesions on the ventral part of the body and 68% had foot lesions. After excluding flea allergy dermatitis by implementing strict flea control, 60% of the dogs presented with dorsal distribution of skin lesions. Dogs with ventral lesions were younger when clinical signs first appeared (P &amp;lt; 0.05). Most of the dogs were allergic to dust and/or dust mites (75.6%), with weeds and trees as the next most common allergens. CAD is similar worldwide, but geographic differences may be attributable to genetic pools and allergen loading. This study also shows that early onset of clinical signs, especially in breeds predisposed to CAD and with a dorsal distribution of skin lesions, should not rule out the diagnosis of CAD. &amp;nbsp;

A prospective study on the clinical features of chronic canine atopic dermatitis and its diagnosis

Canine atopic dermatitis (CAD) is a multifaceted disease associated with exposure to various offending agents such as environmental and food allergens. The diagnosis of this condition is difficult because none of the typical signs are pathognomonic. Sets of criteria have been proposed but are mainly used to include dogs in clinical studies. The goals of the present study were to characterize the clinical features and signs of a large population of dogs with CAD, to identify which of these characteristics could be different in food-induced atopic dermatitis (FIAD) and non-food-induced atopic dermatitis (NFIAD) and to develop criteria for the diagnosis of this condition. Using simulated annealing, selected criteria were tested on a large and geographically widespread population of pruritic dogs. The study first described the signalment, history and clinical features of a large population of CAD dogs, compared FIAD and NFIAD dogs and confirmed that both conditions are clinically indistinguishable. Correlations of numerous clinical features with the diagnosis of CAD are subsequently calculated, and two sets of criteria associated with sensitivity and specificity ranging from 80% to 85% and from 79% to 85%, respectively, are proposed. It is finally demonstrated that these new sets of criteria provide better sensitivity and specificity, when compared to Willemse and Prélaud criteria. These criteria can be applied to both FIAD and NFIAD dogs.

The role of Ambrosia artemisiifolia allergen in canine atopic dermatitis

Pollens from Ambrosia species have a strong allergenic potential and they represent a complex mixture of at least 52 different antigens. This weed is widespread in Serbia and has a long pollination period (appr. 100 days). Pollens are present in very high concentrations during the pollination season (up to 300 pg/m3 of air). Fifty dogs with a clinical diagnosis of canine atopic dermatitis (CAD) and positive intradermal skin test (IDST) reactions to other environmental allergens were included in this study along with 30 dogs without clinical signs of CAD. Both groups were tested intradermally with Ambrosia artemisiifolia extract in concentration of 1000 PNU/mL (provided by ''Institute of virology, vaccines and sera - Torlak''). We have found that Ambrosia extract was second most common allergen to yield positive intradermal test reactions just after house dust mites. The positive reaction of IDST was observed in 66% of the atopic dogs and in 10% of clinically healthy dogs. Dogs that had a positive reaction on intradermal skin test to Ambrosia pollens, mostly showed secondary skin lesions on the pads and perioral skin. In 88% of cases, Malassezia pachydermatis have been isolated from the skin in an increased number and 64% of dogs had otitis externa. These results indicate, that allergens from Ambrosia artemisifolia are of great importance in the etiopathogenesis of atopic dermatitis in dogs originating from the Belgrade region.

Diagnostic specificity of the Fcε-receptor based allergy screening test

Summary Objective: To evaluate the diagnostic specificity of a Fcε-receptor allergy screening test using serum from clinically non-atopic dogs. Material and methods: In this prospective study allergen-specific IgE levels were measured using the Fcε-receptor method (Allercept® Heska) in the serum from 15 clinically non-atopic dogs, without any history of pruritic skin diseases or recurrent ear diseases. Five crossbreeds and 10 pure breed dogs were included with approximately equal sex distribution. Their age ranged between 2 and 14 years, with a median age of 4 years. A commercially available allergy screening test was performed evaluating three allergen groups: mites (house dust mites and forage mites), moulds and pollens, as well as flea-saliva. Results: All except one dog showed positive results for at least one of the allergen groups. Fourteen dogs were positive for mites (house dust mites and forage mites), five dogs each were additionally positive for flea-saliva antigen and for pollens, respectively; only one dog was positive for moulds. Overall diagnostic specificity of the allergy screening test was 6.7% for mites, 66.6% for flea-saliva and pollens and 93.3% for moulds. Conclusions: The Fcε-receptor based allergy screening test detects a high incidence of allergen-specific IgE among clinically non-atopic dogs. The low diagnostic specificity in this study confirms results of earlier studies with serological monoclonal and polyclonal allergy testing. Clinical relevance: This Fcε-receptor based allergy screening test should not be used to establish the diagnosis of canine atopic dermatitis. Diagnosis of atopic dermatitis in dogs is based on clinical criteria and exclusion of other causes of pruritus. Positive intradermal or serological allergy testing is only a minor diagnostic criterion. Any kind of allergy testing is performed for identification of the relevant allergens in atopic dogs as a precondition for allergen specific immunotherapy.

Evaluation of skin sensitivity in dogs bearing allergic dermatitis to standardized allergenic extract of house dust and storage mites

The objective of the study was to evaluate whether allergenic extracts of five house dust and storage mite species standardized for humans might be used for the diagnosis of canine atopic dermatitis (CAD). Extracts of Dermatophagoides pteronyssinus (Pyroglyphidae), D. farinae (Pyroglyphidae), Blomia tropicalis (Glycyphagidae), Lepidoglyphus destructor (Glycyphagidae) and Tyrophagus putrescentiae (Acaridae) were evaluated by intradermal testing in 20 healthy dogs (control) and 25 dogs with allergic dermatitis. A significant difference in the response was observed between the two groups (p&lt;0.05). Only one dog (5%) in the control group reacted to the intradermal test, whereas 14 dogs (56%) in the allergic group were positive for at least one extract (odds ratio = 24.2). Most of the positive reactions observed in the allergic group occurred against the extracts of T. putrescentiae or L. destructor, each inducing reactions in 10 dogs (40%). D. farinae, D. pteronyssinus e B. tropicalis extracts induced reactions in 7 (28%), 3 (12%) and 3 (12%) dogs, respectively. The allergenic extracts standardized for humans evaluated in the present study may be used as a tool to complement the diagnosis of the disease, as well as to select potential allergen candidates for allergen-specific immunotherapy.

Canine atopic dermatitis: validation of recorded diagnosis against practice records in 335 insured Swedish dogs

A cross-sectional study of insured Swedish dogs with a recorded diagnosis of canine atopic dermatitis (CAD) was performed. In order to validate the correctness of this specific diagnosis in the insurance database, medical records were requested by mail from the attending veterinarians. All dogs with a reimbursed claim for the disease during 2002 were included in the original study sample (n = 373). Medical records were available for 335 individuals (response rate: 89.8%). By scrutinizing the submitted records it was determined that all dogs had been treated for dermatologic disease, and that 327 (97.6%) could be considered to have some allergic skin disease. However, as information regarding dietary trial testing was missing in many dogs the number that were truly atopic could not be determined. The clinical presentation and nature of test diet for dogs with or without response to dietary trial testing was compared for a subset of 109 individuals that had undergone such testing. The only significant difference between these two groups was that the proportion of dogs with reported gastrointestinal signs was higher in the group that subsequently responded to a diet trial. In conclusion, the agreement between the recorded diagnosis in the insurance database and the clinical manifestations recorded in the submitted medical records was considered acceptable. The concern was raised that many attending veterinarians did not exclude cutaneous adverse food reactions before making the diagnosis of CAD.