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Canine atopic dermatitis (AD) is a common, genetically predisposed, inflammatory and pruritic skin disease. The variation in clinical presentations, due to genetic factors, extent of the lesions, stage of the disease, secondary infections, as well as resemblance to other non-atopic related skin diseases, can complicate a diagnosis of canine AD. A s...
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Context 1
... non-seasonal (e.g., dust mites, food) [42]. At the beginning the pruritus may be alesional or associated with primary skin lesions such as erythema and occasionally papules (Table 2) [43,44]. The face, concave aspect of the ear pinnae, ventrum, axillae, in- guinal area, perineal area and distal extremities are most commonly affected in canine AD (Fig. 8) [43], but breed- associated variations of body sites affected by canine AD have been identified (Table 3, Fig. 9) [3]. In more chronic stages secondary skin lesions (Table 2) will occur due to self-trauma, chronic inflammation and secondary in- fections. Typical secondary skin lesions are excoriations, alopecia, lichenification, ...
Citations
... Atopic dermatitis (AD) manifests as a common, often chronic, allergic skin disease in both humans and dogs, characterised by mild-to-severe pruritus and inflammatory skin lesions. 1,2 The pathogenesis of AD involves multiple factors. In 2023, the International Committee on Allergic Diseases of Animals (ICADA) revised the definition of canine AD (cAD) to reflect current knowledge. ...
Background
Itch is a common clinical sign in skin disorders. While the neural pathways of itch transmission from the skin to the brain are well understood in rodents, the same pathways in dogs remain unclear. The knowledge gap hinders the development of effective treatments for canine itch‐related disorders.
Hypothesis/Objectives
This study aimed to investigate the differential gene expression in the dorsal root ganglia (DRGs) between healthy and atopic dogs to identify specific molecules potentially involved in itch signalling and neuroinflammation in canine atopic dermatitis (cAD).
Animals
Two atopic and four healthy dogs.
Materials and Methods
DRGs were collected from atopic and healthy dogs to compare their transcriptional profiles using RNA sequencing.
Results
Principal component and heatmap analyses revealed two distinct clusters separating atopic from healthy dogs. Consistent with this observation, we identified 627 (543 upregulated and 84 downregulated) differentially expressed genes (DEGs) in atopic compared with healthy dogs. We further narrowed down our genes of interest to common DEGs in each atopic dog, which revealed 159 (132 upregulated and 27 downregulated) DEGs. Among these genes, when we focused on itch signalling–associated molecules, P2RY12, IL‐2RG, TLR1 and POSTN were significantly upregulated, while MRGPRD and LPAR3 were both significantly downregulated in atopic dogs compared with those in healthy dogs. Pathway analysis showed a significant upregulation of CREB signalling in neurons, myelination signalling and neuroinflammation signalling pathways in atopic dogs.
Conclusions and Clinical Relevance
Our study suggested that dysregulation of neuroinflammatory pathways might play a role in the pathomechanism of cAD as in humans.
... This could be due to associations between the type of dermatitis condition and pruritus location, which have been observed previously. 1,14 Additionally, pruritus is the primary cause of scratching, but the same is not true for licking as dogs lick for other reasons, such as self-grooming. Only duration of pruritic behavior was measured by the accelerometer; intensity of scratching may provide additional insights into efficacy in that a positive intervention may lead to less vigorous scratching. ...
OBJECTIVE
To evaluate the use of collar-mounted accelerometers to objectively monitor treatment outcomes in canine pruritus.
METHODS
Observational data from 1,803 dogs from 2019 through 2023 were retrospectively analyzed to evaluate the efficacy of collar-mounted accelerometers to assess treatment efficacy for pruritic canine skin diseases. Accelerometer measurements were joined to electronic health records to establish symptoms, diagnoses, and interventions. A directed acyclic graph was used to identify relevant variables to control for, and linear regression was used to model the pruritic behaviors before and after intervention.
RESULTS
Significant reductions in pruritic behaviors, particularly scratching and licking, were observed following interventions. Antibody and immunosuppressant treatments exhibited the most pronounced effects on scratching behavior, with a reduction in scratching of up to 40.9% and 23.4%, retrospectively, in the 30 days following intervention relative to the 14 days prior.
CONCLUSIONS
Collar-mounted accelerometers used to measure pruritic behaviors can detect the effects of interventions for canine pruritus.
CLINICAL RELEVANCE
Pruritus is a common symptom of canine skin diseases, such as atopic dermatitis or allergic dermatitis, which can be difficult to diagnose and manage. This study highlights the use of collar-mounted accelerometers to objectively monitor treatment outcomes for canine pruritus, providing valuable insights into treatment effectiveness that could allow veterinarians and pet owners to optimize management strategies to alleviate the burden of this challenging condition.
... After taking the patient's history and physical examination, some differential diagnoses were considered, such as allergic skin diseases, pyoderma, burns and CADR (HO et al., 2015). The location and characteristics of the lesion are not commonly observed in allergic diseases (HENSEL et al., 2015). Considering the main differential diagnoses, it was possible to establish the diagnosis of bacterial pyoderma by cytology, with a probable secondary cause, not requiring microbiological examination for confirmation at this time (HENSEL et al., 2015). ...
... The location and characteristics of the lesion are not commonly observed in allergic diseases (HENSEL et al., 2015). Considering the main differential diagnoses, it was possible to establish the diagnosis of bacterial pyoderma by cytology, with a probable secondary cause, not requiring microbiological examination for confirmation at this time (HENSEL et al., 2015). After the cytology results, it was decided to start treatment with a topical anti-inflammatory, antibiotic, antimycotic, anesthetic, anti-allergic and antipruritic medication (Crema 6A, Labyes). ...
Cutaneous adverse drug reactions (CADR) are unexpected dermatological reactions caused by medications. CADRs may mimic any type of dermatosis, including contact dermatitis (CD). This paper described a case of a CADR resulting from the topical use of benzyl benzoate in a dog. A two year old unneutered male Pit Bull was referred for a medical consultation due to skin lesions in the cervical region. The owner reported bathing this dog routinely using 10% benzyl benzoate (BB)-based scabicidal soap, without rinsing it off at the end. An ulcerative, draining maculopapular skin lesion was observed in the dorsal region of the neck extending to the interscapular region. A surgical skin biopsy was then performed and microscopically an area of ulcerated epidermis was observed with apoptosis of transepidermal keratinocytes associated with a mixed infiltrate. Interface dermatitis with a predominance of lymphocytes in the hair follicle region, multifocal areas of mild spongiosis, mild vacuolar degeneration of keratinocytes and sub-corneal pustule was also identified. Bathing with the BB-based scabicidal soap was discontinued and a new shampoo was introduced. Topical dexamethasone, neomycin sulfate, bacitracin zinc, griseofulvin, and benzocaine treatment was started. Within 48 hours of treatment, skin revitalization was already significant and total healing took place approximately three weeks after the first appointment. Considering the findings observed in this case, it can be concluded that prolonged topical exposure to BB, due to misuse of the product, may cause a CADR characterized by irritant CD in dogs.
... Adverse food reactions (AFRs) in dogs is a term used to describe any abnormal response to an ingredient in their diet [6]. It primarily involves the skin and gastrointestinal system and can be broadly classified into food allergies (immunologically mediated) and food intolerances (non-immunologically mediated) [7]. Adverse food reactions in dogs are estimated to account for about 1-2% of all canine diseases [8][9][10]. ...
... Dermatological signs predominated when the study was performed by dermatologists, wherein 261 dogs (71%) presented dermatological signs only, 10 dogs (3%) showed only gastrointestinal signs, and 97 dogs (27%) exhibited both gastrointestinal and dermatological signs [15]. Elimination diets have been considered the gold standard for diagnosing AFRs [7,16,17]. This process involves feeding the dog a novel protein or hydrolyzed protein diet for 8-12 weeks. ...
... The medical history information for each dog in the AFR group during the challenge diet protocol used to diagnose AFR was provided in Supplementary Data S1. The diagnosis of AFR was made using standard procedures [7]. AFR dogs were managed at the dermatology clinic of a small animal hospital. ...
Can black soldier fly (BSF) larvae be a protein substitute for managing adverse food reactions (AFRs) in dogs, specifically those with dermatitis? We evaluated BSF larvae’s safety, tolerance, and effectiveness as a novel protein source in dogs with AFRs. Sixteen dogs, including eight healthy controls and eight diagnosed with AFRs, were fed a diet containing BSF larvae for four weeks. Skin conditions, including dermatological lesions and Pruritus Visual Analog Scale (PVAS) scores, and gastrointestinal signs, including relevant clinical signs, stool consistency, and hematological and biochemical parameters, were monitored. No significant gastrointestinal side effects were observed. The control and AFRs groups maintained stable body weights, while stool consistency scores did not change significantly. Moreover, skin reaction data obtained before the study were collected through interviews with the owners. The mean PVAS scores in the AFRs group were significantly higher (p < 0.05) during the self-control period (6.0 ± 1.6) when compared with other periods. However, no significant differences (p > 0.05) were observed between the pre-study baseline (2.0 ± 1.1) and scores at 2 weeks (2.3 ± 1.5) and 4 weeks (2.4 ± 1.2) of feeding with BSF-based food, which indicated that BSF larvae did not exacerbate pruritic symptoms. Hematology and blood chemistry remained within normal ranges in all dogs, indicating no adverse effects on overall health. BSF larvae were well tolerated by AFR-affected and control dogs, with no adverse clinical outcomes. The findings suggest that BSF larvae may offer a better, sustainable alternative protein source for managing AFRs in dogs, particularly in those on hypoallergenic diets. Further long-term studies are needed to confirm these results and assess the broader implications of BSF larvae diets on canine health.
... Dogs diagnosed with cAD, in accordance with published recommendations, were enrolled at 25 veterinary clinics in Germany, Hungary, Ireland and Portugal. 19,20 The study was initially designed as a 56-day prospective, double-blinded, randomised, positive-controlled field study to assess the efficacy and safety of ilunocitinib in comparison to oclacitinib for the treatment of pruritus and skin lesions in atopic dogs. During the inlife phase, the protocol was amended to include an optional continuation phase, wherein dogs could continue in the same treatment group for a total study duration of 112 days. ...
Background
Janus kinase inhibitors (JAKi) have been shown to reduce pruritus and improve associated inflammatory skin lesions in canine atopic dermatitis (cAD).
Objective
To evaluate the efficacy and safety of ilunocitinib, in comparison to oclacitinib, for the control of cAD in a randomised, blinded trial.
Animals
Three‐hundred‐and‐thirty‐eight dogs with cAD.
Materials and Methods
Dogs were randomised to receive oclacitinib (0.4–0.6 mg/kg twice daily for 14 days; then once daily) or ilunocitinib (0.6–0.8 mg/kg once daily), for up to 112 days. Owners assessed pruritus using an enhanced Visual Analog Scale (PVAS). Investigators assessed skin lesions using the Canine Atopic Dermatitis Extent and Severity Index, 4th interaction (CADESI‐04).
Results
Reduction in pruritus and CADESI‐04 scores was similar for both treatment groups from Day (D)0–D14. PVAS scores increased between D14 and D28 for oclacitinib and decreased for ilunocitinib. On D28 to D112, mean PVAS and CADESI‐04 scores were significantly lower for ilunocitinib compared to oclacitinib (p ≤ 0.003 and p ≤ 0.023, respectively). On D28 to D112, a greater number of ilunocitinib‐treated dogs achieved clinical remission of pruritus (i.e. PVAS score <2). Subjective assessment of overall response was significantly better for ilunocitinib on D28 to D112 (p ≤ 0.002). Both drugs demonstrated similar safety throughout the study.
Conclusions and Clinical Relevance
Ilunocitinib rapidly and safely controlled signs of cAD. Ilunocitinib demonstrated significantly better control of pruritus and skin lesions compared to oclacitinib, with more dogs achieving clinical remission of pruritus.
... We enrolled 34 dogs with atopic dermatitis (AD) diagnosed based on standard methods [36]; details of their signalment can be found in Supplementary Table S1. The breeds most often included were Labrador (5) and other retrievers (2), French bulldogs (4), and German shepherd dogs (3). ...
Cross-reactive carbohydrate determinants (CCDs) are complex N-glycans shared among allergens of plant, insect venom, and nematode origin. In allergic humans, IgE anti-CCD often develop and cause discrepancies between serological and skin tests. Overall, CCD-IgE are believed to be of low pathogenic relevance. IgE-targeting CCDs are also detected in companion animals, but their pathogenic potential and biological relevance are unknown. Herein, we first establish that, in 34 dogs with atopic dermatitis, the presence of serum anti-CCD IgE was detected in 14 pets (41.2%). In dogs, as in humans, IgE-targeting CCDs are heterogeneous, as they differentially recognized four distinct CCD-expressing proteins. The presence of CCD-IgE was associated with a higher and more frequent recognition of plant extracts in serological but not intradermal tests. Two different CCD-expressing proteins did not elicit immediate reactions when injected intradermally in dogs with detectable serum anti-CCD IgE. Similarly, two different CCD-expressing proteins did not induce the activation of mast cells passively transferred with canine anti-CCD IgE. Altogether, these results suggest that in dogs, as in humans, anti-CCD IgE are likely to have little pathogenic potential and blocking them in allergen-specific IgE serological tests is warranted to avoid false-positive results to plant extracts.
... A predisposição genética desempenha um papel crucial, com algumas raças sendo mais afetadas que outras, como o West Highland White Terrier e o Golden Retriever Santos & Santos, 2016;Zanon et al., 2008). A exposição a alérgenos ambientais, como pólen, ácaros e mofo, pode desencadear ou exacerbar a condição (Hensel et al., 2015;Henselm et al., 2009). Além disso, algumas alergias alimentares podem contribuir para o desenvolvimento da DAC, tornando essencial a identificação e eliminação de alimentos alergênicos da dieta do cão (Santos & Santos, 2016;Zanon et al., 2008). ...
The development of canine atopic dermatitis (CAD) and recurrent otitis are frequently interrelated conditions in dogs, representing a significant challenge in veterinary diagnosis and treatment. This case study details the experience of the dog crossbred (SRD), adopted with year of age, who suffers from CAD and frequent episodes of recurrent otitis caused by Malassezia sp. The objectives of this study were to investigate the relationship between CAD and recurrent otitis, as well as to develop an integrated approach for the effective management of these conditions. The dog underwent a comprehensive clinical evaluation, which included a detailed history, observation of symptoms, and allergy testing. Treatment consisted of the use of antihistamines, corticosteroids and immunosuppressants, in addition to the application of monoclonal antibodies every four weeks to control itching. Immunotherapy has been introduced to modulate the long-term immune response. Recurrent otitis was managed with regular cleaning and topical treatments with Chlorhexidine; miconazole and omega 3,6 and 9, applied three times a week, complemented by a restrictive diet to minimize food allergens. The results showed that the combination of these strategies provided significant relief from dog symptoms, improving their quality of life. The integrated approach, including environmental control, drug therapy and dietary management, proved effective in controlling CAD and recurrent otitis. This study highlights the importance of personalized and ongoing management, as well as suggesting the need for more research into new therapeutic approaches for these chronic conditions. It is concluded that coordination between veterinarians and owners is essential for the success of treatment and the well-being of affected dogs.
... For this reason, current guidelines recommend a comprehensive physical examination and a detailed clinical history to rule out other skin conditions with comparable lesions. 1 Treatment options for canine AD include topical and systemic anti-inflammatory and antipruritic medications. Allergen-specific immunotherapy (ASIT) is considered the only therapeutic option able to revert the allergic state of a patient over time. ...
... Intradermal allergen testing (IDAT) is commonly used for allergen identification for ASIT. 1,2 It is noteworthy to remember that allergen testing (intradermal or serological) should not to be used to make a diagnosis of canine AD, and rather only to select allergens to be included in the ASIT. 1 The IDAT is characterised by the intradermal injection of several relevant allergens, followed by evaluation for erythema and swelling forming within 20 min of the injections. Owing to the nature of the procedure, sedation of the dog is recommended. ...
... 1,2 It is noteworthy to remember that allergen testing (intradermal or serological) should not to be used to make a diagnosis of canine AD, and rather only to select allergens to be included in the ASIT. 1 The IDAT is characterised by the intradermal injection of several relevant allergens, followed by evaluation for erythema and swelling forming within 20 min of the injections. Owing to the nature of the procedure, sedation of the dog is recommended. ...
Background
Intradermal allergen testing (IDAT) is commonly used to formulate allergen‐specific immunotherapy, a pillar treatment for canine atopic dermatitis. Many sedatives have shown histaminergic or anti‐histaminergic effects and thus been deemed unsuitable for IDAT.
Objective
The goal of this study was to determine whether, in healthy dogs, dexmedetomidine (Dexdomitor) or a 1:20 combination of medetomidine and vatinoxan (Zenalpha) will affect intradermal reactions compared to unsedated dogs.
Animals
Ten privately owned healthy dogs were enrolled in this equivalence study.
Materials and Methods
Wheal formation was subjectively and objectively assessed in conscious then sedated dogs. Dogs were randomly sedated with either Dexdomitor (dexmedetomidine [0.5 mg/m²]) or Zenalpha (medetomidine [1 mg/m²/vatinoxan] 20 mg/m²) intramuscularly. Once sedated, five 10‐fold histamine (100–0.01 μg/mL) and compound 48/80 (200–0.02 μg/mL) dilutions were intradermally injected into the lateral thorax. The study was repeated on the opposite side with the alternative sedation 1 week later. Quality of sedation, cardiorespiratory function and rectal temperature were recorded every 5 min.
Results
There was no difference in the median values of the reactions with either sedative when compared to unsedated dogs. Dexdomitor and Zenalpha achieved an equivalence in both subjective and objective scoring systems for all concentrations tested. A faster median time to sedation (10 vs. 18 min, p = 0.013) was seen with Zenalpha compared to Dexdomitor. Although both sedatives depressed the cardiovascular function, such parameters were less affected by Zenalpha than by Dexdomitor (p ≤ 0.001).
Conclusions and Clinical Relevance
Owing to the lack of effects on wheal formation, both sedatives are appropriate for sedating dogs undergoing IDAT. Although, such results should be validated in allergic dogs. Zenalpha may induce more rapid and reliable sedation than Dexdomitor.
... Food allergies involve various responses triggered by the immune system after ingesting foods, manifesting up to 48 hours after initial contact [1,2]. Allergic reactions to different food components can cause changes in various systems of the body, with dermatological manifestations, known as food dermatitis, being a significant concern for pet owners. ...
... According to Olivry and Mueller [4], the prevalence of dogs with food-related skin reactions is 1 to 2% among all cases, and can reach up to 24% of dermatological cases. Additionally, food allergies may manifest as gastrointestinal signs and are often characterized by vomiting, soft stools, diarrhea, flatulence, and an increased frequency of bowel movements, and are less common than dermatitis [1]. ...
Food allergy triggers an immune response to dietary proteins, resulting in food rejection and dermatological and gastrointestinal manifestations. The preferred therapies include diets with hydrolyzed proteins or unusual single-source proteins, with insect protein emerging as a promising option, with no reported allergic reactions in dogs with a food allergy. In this case study, the effects of including black soldier fly larva (BSFL) meal were observed in a 5-year-old spayed beagle previously diagnosed with a food allergy. The objective was to assess the potential of BSFL meal as an adjunct in treating a food allergy. As part of the protocol, two nutritionally very similar diets were used, differing only in the protein source: the control diet, with poultry by-product meal; and the BSFL diet, which completely replaced the poultry by-product meal. After a 12-day adaptation period to the BSFL diet, the dog showed no gastrointestinal changes, maintaining an adequate fecal score and no clinical signs of the disease. A challenge test with the control diet resulted in episodic gastrointestinal symptoms, which were reversed within two days by reintroducing the BSFL diet. The BSFL protein-based diet was effective in controlling the dog’s clinical signs.
... The most common characteristics of CAD are moderate to severe pruritus, often preceded and accompanied by erythema, papules, spontaneous hair loss, shedding, hyperpigmentation, and lichenification (5)(6)(7). However, due to the diversity of manifestations, clinical signs are not specific, so a preliminary examination cannot make a definitive diagnosis. ...
Canine atopic dermatitis (CAD) is a common skin disease in dogs. Various pathogenic factors contribute to CAD, with dust mites, environmental pathogens, and other substances being predominant. This research involved comprehensive statistical analysis and prediction of CAD in China, using data from 14 cities. A distributed lag nonlinear model (DLNM) was developed to evaluate the impact of environmental factors on CAD incidence. Additionally, a seasonal auto-regressive moving average (ARIMA) model was used to forecast the monthly number of CAD cases. The findings indicated that CAD mainly occurs during June, July, August, and September in China. There was a positive correlation found between CAD incidence and temperature and humidity, while a negative correlation was observed with CO, PM2.5, and other pollutants.