Evaluation of aural masses submitted as inflammatory polyps in 20 dogs (2000-2020).

BACKGROUND: Canine non-neoplastic aural polypoid masses (APMs) are uncommon, with few published studies. OBJECTIVES: The aim of this retrospective study was to characterise the clinical presentation, diagnostic imaging and histopathological results for APMs submitted as aural inflammatory polyps (AIPs). ANIMALS: Twenty dogs with APMs evaluated at a veterinary teaching hospital. MATERIALS AND METHODS: Cases were selected by searching computerised medical records from 2000 to 2020, using keywords 'canine', 'aural/otic polyp' and 'aural/otic inflammatory mass'. Histological samples and medical records were reviewed. RESULTS: In 14 of 20 dogs, external ear canal masses were characterised by keratinised squamous epithelium with or without adnexa. Tympanic bulla origin was confirmed in four of 20 dogs by the presence of cuboidal to ciliated columnar epithelium, with or without squamous epithelium. The site of origin could not be determined in two dogs. Diagnostic imaging (MRI or CT) confirmed APM presence in 14 of 20 dogs. Otitis media was diagnosed in four of four tympanic bulla APMs and seven of 13 ear canal APMs. In 18 of 20 dogs, debulking, traction avulsion, and total ear canal ablation and bulla osteotomy led to APM resolution in two of eight, four of six and four of four dogs, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Type of epithelium was a key feature in determining the APM origin, and interpretation in conjunction with video otoscopy and diagnostic imaging was crucial. Canine APMs more commonly arose from the ear canal. Tympanic bulla APMs and APMs of undetermined origin were comparable to feline AIPs. Regardless of APM origin site, debulking had the greatest likelihood of recurrence.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Extensive progressive pigmented viral plaques in a Chihuahua dog.

Extensive exophytic pigmented viral plaques developed on a Chihuahua dog causing pruritus and discomfort. Neither the medical treatments used nor a papillomavirus vaccine resulted in clinical improvement. Laser surgery removed some plaques, yet others developed. This case illustrates the difficulty in treating viral plaques and the progressive nature of this disease.

De vastes plaques virales pigmentées exophytiques se sont développées sur un Chihuahua, provoquant prurit et inconfort. Ni les traitements médicaux utilisés ni un vaccin contre le papillomavirus n'ont entraîné d'amélioration clinique. La chirurgie au laser a enlevé certaines plaques, mais d'autres se sont développées. Ce cas illustre la difficulté de traiter les plaques virales et le caractère évolutif de cette maladie.

Se desarrollaron extensas placas virales pigmentadas exofíticas en un perro Chihuahua que causaban prurito y malestar. Ni los tratamientos médicos utilizados ni la vacuna contra el virus del papiloma resultaron en una mejoría clínica. La cirugía con láser eliminó algunas placas, pero se desarrollaron otras. Este caso ilustra la dificultad para tratar las placas virales y la naturaleza progresiva de esta enfermedad.

Placas virais pigmentadas exofíticas extensas se desenvolveram em um cão Chihuahua, causando prurido e desconforto. Nem os tratamentos médicos utilizados nem a vacina contra o papilomavírus resultaram em melhora clínica. A cirurgia a laser removeu algumas placas, mas outras se desenvolveram. Este caso ilustra a dificuldade no tratamento das placas virais e a natureza progressiva da doença.

Transient Horner's syndrome and ipsilateral facial hypopigmentation in an acromelanistic cat.

Horner's syndrome (HS) occurs when the sympathetic nerve pathway is disrupted. This case report describes a cat with acromelanism that developed unilateral facial hypopigmentation concurrently with HS after an oesophagostomy tube was placed. Both the hypopigmentation and HS resolved completely following removal of the oesophagostomy tube.

Le syndrome de Horner (HS) survient lorsque la voie nerveuse sympathique est perturbée. Ce rapport de cas décrit un chat atteint d'acromélanisme qui a développé une hypopigmentation faciale unilatérale en même temps qu'une HS après la mise en place d'une sonde d'oesophagostomie. L'hypopigmentation et l'HS ont disparu complètement après le retrait de la sonde d'œsophagostomie.

El síndrome de Horner (HS) ocurre cuando se interrumpe la transmisión nerviosa a través del nervio simpático. Este caso clínico describe un gato con acromelanismo que desarrolló hipopigmentación facial unilateral al mismo tiempo que HS después de la colocación de una sonda de esofagostomía. Tanto la hipopigmentación como la HS se resolvieron por completo tras la retirada del tubo de esofagostomía.

A síndrome de Horner (SH) ocorre quando a via do nervo simpático é danificada. Este relato de caso descreve um gato com acromelanismo que desenvolveu hipopigmentação facial unilateral concomitantemente com SH após a colocação de um tubo de esofagostomia. Tanto a hipopigmentação quanto a HS se resolveram completamente após a remoção do tubo de esofagostomia.

Preliminary study of the stability of dexamethasone when added to commercial veterinary ear cleaners over a 90 day period.

BACKGROUND: Topical corticosteroids are commonly used in the management of allergic otitis externa to diminish inflammation. A common strategy is to make compounded solutions of dexamethasone in ear cleaner. HYPOTHESIS/OBJECTIVES: The objective of this study was to determine the stability of dexamethasone when added to four commercial ear cleaners (ec): designated ecA, ecB, ecC and ecD. METHODS AND MATERIALS: Two concentrations (0.1 and 0.25 mg/mL) of dexamethasone were formulated for each cleaner solution from a 2 mg/mL solution and stored in the original manufacturers' bottles at two temperatures: room (22 ËšC) and refrigerated (4 ËšC). Samples were evaluated in triplicate, using liquid chromatography-tandem mass spectrometry at 10 time points over 90 days. The mean and standard deviation were calculated for each time point. RESULTS: A solution was considered stable if the dexamethasone value remained >90% of the target concentration. All dexamethasone solution values were stable to 90 days, except two solutions for ecA; the 0.25 mg/mL dexamethasone concentration was only stable to 14 (4 ËšC) and 21 days (22 ËšC). CONCLUSIONS AND CLINICAL IMPORTANCE: These results provide preliminary evidence in support of pharmaceutical stability data for dexamethasone when included in the above compounded solutions at the noted concentrations and temperatures.

A case of atypical multifocal nodular eosinophilic dermatosis in a Labrador retriever dog.

BACKGROUND: A dog with gastrointestinal signs and a history of administration of multiple drugs developed acute multifocal to coalescing ulcerative nodules and a large plaque. OBJECTIVE: To describe abnormal nodular clinical lesions with an unexpected superficial and deep severe eosinophilic perivascular to interstitial inflammation. ANIMAL: A 7-year-old spayed female Labrador retriever METHODS AND MATERIALS: Blood tests, faecal and urinalysis, and abdominal radiographs were performed; skin biopsy samples were taken for cytological, culture and histopathological analyses. RESULTS: The blood tests, faecal, urinalysis and radiographs were within normal limits. Cytological results revealed inflammatory cells and cultures had no growth. Histopathological evaluation revealed dermal and subcutaneous oedema, mucin deposition and perivascular to interstitial inflammation predominated by eosinophils with occasional very small intralesional dense aggregates of eosinophils centred on collagen bundles, eosinophilic exocytosis and small eosinophilic pustules. Focal subepidermal fibrin exudation and haemorrhage resulted in epidermal detachment and ulceration. Clinical resolution of the dermatological and gastrointestinal signs was seen with the withdrawal of prior medications and administration of a tapering course of anti-inflammatory doses of prednisolone. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is a novel nodular clinical and eosinophilic histopathological pattern combination. This case offers evidence of a spectrum of sterile eosinophilic dermatoses rather than multiple different disease processes.

Assessment of the clinical accuracy of serum and saliva assays for identification of adverse food reaction in dogs without clinical signs of disease.

OBJECTIVE: To assess the clinical accuracy of 2 serum-based assays and 1 saliva-based assay for detection of adverse food reaction (AFR) in dogs without clinical signs of disease. ANIMALS: 30 healthy client-owned dogs. PROCEDURES: Dog owners completed an online survey to collect comprehensive information about their pets' diet history. From each dog, serum and saliva samples were obtained and submitted for AFR testing by means of 3 assays that assessed the immunoglobulin response to 24 foods. Assays A and B measured food allergen-specific IgE concentrations in serum, whereas assay C measured food allergen-specific IgA and IgM concentrations in saliva. Descriptive data were generated, and Fisher exact tests were used to assess the respective associations between positive test results and specific food ingredients to which dogs were exposed. RESULTS: Assays A, B, and C yielded positive results for 26, 18, and 30 dogs, respectively. All dogs had positive results for at least 1 assay. The median (range) number of foods or ingredients to which dogs tested positive was 10.5 (0 to 24) for assay A, 1 (0 to 13) for assay B, and 12.5 (4 to 22; IgM) and 3 (0 to 24; IgA) for assay C. Positive test results were not significantly associated with prior food exposure. CONCLUSIONS AND CLINICAL RELEVANCE: Saliva and serum assays for AFR often yielded positive results for apparently healthy dogs and are not recommended for clinical use. Elimination diet trials remain the gold standard for diagnosis of AFR in dogs.

An unresponsive progressive pustular and crusting dermatitis with acantholysis in nine cats.

BACKGROUND: Between 2000 and 2012, nine cats were examined with a visually distinctive, progressive crusting dermatitis that was poorly responsive to all attempted therapies. OBJECTIVES: Documentation of clinical and histopathological findings of this disease. ANIMALS: Nine privately owned cats. METHODS: Retrospective study. RESULTS: Eight neutered males and one (presumably spayed) female ranging in age from two to eight years, presented for a progressive, well-demarcated, crusting dermatitis with variable pruritus of 1.5 months to five years duration. All cats lived in northern California, USA; seven lived within a 30 mile radius. Two males were littermates. Histopathological investigation showed both parakeratotic and orthokeratotic crusts, intraepidermal pustules and superficial folliculitis with rare to frequent acantholytic cells. Bacterial and fungal cultures were performed in six cats: meticillin-susceptible Staphylococcus pseudintermedius was isolated in three cats, two colonies of Trichophyton terrestre and three of Malassezia pachydermatis were isolated from one cat each. Treatment with various antibiotics, antifungal and a variety of immunosuppressive medications did not alter the progressive nature of the skin disease. CONCLUSIONS AND CLINICAL IMPORTANCE: The described disease shares some clinical and histopathological features with pemphigus foliaceus, but the lack of response to treatment, its progressive nature and the possible relatedness of some of the cats set it apart. The aetiology of this acantholytic dermatitis remains unknown.

Afoxolaner and fluralaner treatment do not impact on cutaneous Demodex populations of healthy dogs.

BACKGROUND: Fluralaner and afoxolaner are isoxazolines licensed for the treatment of flea and tick infestations. Isoxazolines have also shown efficacy for treatment of demodicosis. Nothing is known about the impact of these compounds on the populations of Demodex in healthy dogs. HYPOTHESIS/OBJECTIVES: The objective of this study was to measure the prevalence of Demodex in the skin of healthy dogs prior to and following the use of either afoxolaner or fluralaner, using real-time PCR (RT-PCR) for Demodex DNA. Our hypothesis was that the use of an isoxazoline at the labelled dose would eliminate Demodex populations from the skin of healthy dogs. ANIMALS AND METHODS: Twenty healthy dogs with no history of skin disease were recruited. Dogs were divided into two groups of ten, with each group receiving afoxolaner or fluralaner for the 90 day study period. Hairs were plucked from three body sites on Day 0 prior to medication administration, then again on days 30 and 90. RT-PCR amplifying Demodex DNA was performed on all samples. RESULTS: At Day 0 (prior to treatment), five of the 20 dogs were positive for Demodex DNA at least in one skin site (25%). At Day 60, three of 18 dogs were positive (16.7%) and on Day 90, six of 20 dogs were positive (30%). No significant difference in numbers of positive dogs was found between groups or timepoints. CONCLUSION: Treatment with afoxolaner or fluralaner does not impact on cutaneous Demodex populations of normal dogs over a 90 day period.

Clinical characteristics of doxorubicin-associated alopecia in 28 dogs.

BACKGROUND: Chemotherapy-induced alopecia (CIA) is common in humans, but there are limited reports describing the clinical features of CIA in dogs. OBJECTIVES: To describe the epidemiological and clinical characteristics of doxorubicin-associated alopecia (DAA) in canine patients at a teaching hospital from 2012 to 2014. ANIMALS: Signalment, diagnosis, treatment protocols and clinical examination findings were recorded in 150 dogs treated with doxorubicin from 2012 to 2014. METHODS: Medical records were searched retrospectively for the keywords "alopecia" and "hypotrichosis." Dogs were excluded if the causal link of hair loss was unclear. RESULTS: Doxorubicin-associated alopecia was reported in 28 of 150 dogs (19%). Two parameters were statistically associated with the development of DAA: coat-type and cumulative doxorubicin dose. Dogs with curly or wire-haired coat-type were significantly more likely to develop DAA than dogs with straight-haired coat-type [χ2 (1, N = 147) = 30, P < 0.0001]. After adjusting for sex, weight and doxorubicin dose, the odds of dogs with curly or wire-haired coat-type developing DAA were 22 times higher than those with straight-haired coat-type (P < 0.0001). Dogs that developed DAA received a significantly higher median cumulative doxorubicin dose (103.0 versus 84.5 mg/m2 ; P = 0.0039) than those that did not develop DAA. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs treated with doxorubicin may be at risk for developing DAA. This risk increases as the cumulative dose of doxorubicin increases, and with a curly or wire-haired coat-type.

Calcinosis cutis in dogs: histopathological and clinical analysis of 46 cases.

BACKGROUND: Calcinosis cutis is well recognized in dogs with endogenous hyperglucocorticism and iatrogenic hyperglucocorticism, but the pathogenesis is still unclear. OBJECTIVES: The objectives of the study were to identify possible correlations between histopathological patterns of dermal mineralization in skin biopsies and underlying causes for calcinosis cutis in dogs, as well as to determine breed predilection and age of onset for dogs within a hospital population. In addition, mineral analysis was performed on four biopsy samples. ANIMALS: Forty-six dogs with histopathologically confirmed calcinosis cutis were evaluated. METHODS: Medical records and histological sections of dogs with calcinosis cutis diagnosed by histopathology over a 21 year period were reviewed. Infrared spectrometry was used to identify the mineral in the paraffin blocks. Exact chi-squared test was used to identify breed predispositions, while a Mann-Whitney U-test was used to identify age correlations. RESULTS: Labrador retrievers, Rottweilers, boxers and Staffordshire terriers were the breeds most commonly affected in this study. Most dogs had either an exogenous or an endogenous source of corticosteroids, with the exception of five dogs with renal insufficiency. In the majority of cases, mineralization was found throughout the entire dermis. The average age of onset of calcinosis cutis for dogs with endogenous hyperglucocorticism was older than that of dogs with iatrogenic hyperglucocorticism. Using infrared spectrometry, apatite crystals were found to be the source of mineral. CONCLUSIONS AND CLINICAL IMPORTANCE: There was no observable difference in the histopathological pattern of calcinosis cutis from dogs with endogenous hyperglucocorticism versus iatrogenic hyperglucocorticism. While glucocorticoid therapy appears to predispose dogs to developing calcinosis cutis, it remains unclear whether there is a specific dose or combination of factors that initiates the mineral deposition. Furthermore, the mineral deposition in dogs with calcinosis cutis was found to be apatite.

Oral vitamin A as an adjunct treatment for canine sebaceous adenitis.

Medical records of dogs with sebaceous adenitis diagnosed by histopathology over an 18-year period were reviewed. From a total of 40 cases, 24 were treated with oral vitamin A. Dogs ranged from 9 months to 12 years of age at the time of disease onset. Purebred as well as mixed-breed dogs were affected. Akitas represented approximately one-third of the affected population. No sex predilections were observed. Vitamin A was administered for a minimum of 1 month. Doses varied from 380 to 2667 IU/kg/day, with a mean of 1037 IU/kg/day. Two dogs received oral vitamin A exclusively. Concurrent treatments included systemic antibiotics, systemic antifungal medications, fatty acid supplementation and various topical treatments. Of 24 dogs treated with vitamin A, three were lost to follow-up. Twelve owners were satisfied with the overall appearance of their dogs, reporting ≥25% improvement in clinical signs, including level of pruritus, amount of scale, alopecia and overall coat quality, compared with pretreatment appearance. Three owners observed adequate initial improvement, with regression to pretreatment state within 6 months of starting treatment. Two owners reported 25-50% improvement in clinical signs while on oral vitamin A supplementation; however, changes were attributed to concurrent topical treatment. Six owners reported no improvement and discontinued oral administration of vitamin A within 7 months. No correlations could be made between vitamin A dosage and response to treatment; prognoses could not be made based on clinical and histopathological findings.