Polyautoimmunity manifest as inflammatory myopathy, uveitis, and progressive cutaneous depigmentation in a mixed breed dog: a case report.

BACKGROUND: Polyautoimmunity is the expression of more than one autoimmune disease in a single patient. This report documents polyautoimmunity in a mixed breed dog with concurrent uveitis, cutaneous depigmentation, and inflammatory myopathy. CASE PRESENTATION: A 1-year-old male neutered mixed breed dog was presented for progressive generalized leukotrichia and leukoderma, bilateral panuveitis, and masticatory muscle atrophy. The latter progressed to myositis of lingual, pharyngeal, and masticatory muscles confirmed by biopsy. Temporalis muscle was completely replaced by adipose and fibrous tissue, and necrotic myofibers with extensive infiltration of mononuclear cells indicated active myositis of lingual muscle. Skin biopsies showed severe melanin clumping in epidermis, hair follicles, and hair shafts, and perifollicular pigmentary incontinence. Uveitis, depigmentation, and myositis affecting the masticatory, pharyngeal, and tongue muscles were diagnosed based on clinical, histological, and laboratory findings. CONCLUSIONS: To the authors' knowledge, this is the first report of concurrent uveitis, progressive cutaneous depigmentation, and inflammatory myopathy in a dog.

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.

Locally extensive follicular hamartomas with concurrent follicular cysts and dermoid cysts on the head of a dog.

A 5-month-old, male intact Australian shepherd dog was presented with nodular lesions affecting the dorsal head. A locally diffuse form of follicular hamartomas, with concurrent dermoid cysts and follicular cysts, was diagnosed by histopathological examination. Complete surgical excision of the affected skin and closure with a subdermal plexus advancement flap led to long-term resolution.

Un berger australien mâle intact âgé de 5 mois a été présenté avec des lésions nodulaires affectant la face dorsale de la tête. Une forme localement diffuse d'hamartomes folliculaires, avec des kystes dermoïdes et des kystes folliculaires concomitants, a été diagnostiquée par examen histopathologique. L'éxérèse chirurgicale complète de la peau atteinte et la fermeture avec un lambeau d'avancement du plexus sous-cutané ont conduit à une résolution à long terme.

Un perro pastor australiano macho entero de 5 meses de edad se presentó con lesiones nodulares que afectaban el dorso de la cabeza. Mediante examen histopatológico se diagnosticó una forma localmente difusa de hamartomas foliculares, con quistes dermoides y quistes foliculares concurrentes. La escisión quirúrgica completa de la piel afectada y el cierre con una zona avanzada en colgajo del plexo subdérmico condujo a una resolución a largo plazo.

Retrospective case series: Necrotising fasciitis in 23 dogs.

BACKGROUND: Necrotising fasciitis (NF) is a rare, rapidly progressive subcutaneous bacterial infection. Few studies have characterised NF in dogs. HYPOTHESIS/OBJECTIVES: To retrospectively describe clinical and laboratory findings, with treatments and outcomes, in dogs with NF. ANIMALS: Twenty-three client-owned dogs treated at a veterinary teaching hospital between 1998 and 2021. MATERIALS AND METHODS: Medical records and laboratory data from 23 dogs diagnosed with NF were reviewed. RESULTS: Male dogs were significantly over-represented (p = 0.003). The most common presenting complaint was sudden lameness. Infection occurred in one or two limbs in 19 of 23 dogs, with right hindlimbs most often affected (13 of 23). Pitting oedema was evident in 14 of 23 dogs. Antibiotic and nonsteroidal anti-inflammatory drugs were administered before presentation in nine and 13 of 23 dogs, respectively. Common clinicopathological abnormalities included hypoalbuminemia, hyponatremia, elevated liver enzymes, elevated creatine kinase, increased bands and lymphopenia. Streptococcus canis was isolated from 18 of 23 dogs. Histopathological features included acute necrosis and severe neutrophilic inflammation. Fifteen dogs were euthanised or died, while surgical intervention led to survival in eight of 23 dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs presenting for acute swelling of a limb with oedema should have the diagnosis of NF considered and early surgical intervention might increase survival.

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.

Multicentric B-cell lymphoma with presumed paraneoplastic generalized cutaneous sclerosis in a dog.

BACKGROUND: Reports of dermal sclerosis in dogs include scleroderma or morphea of unknown cause, cicatricial alopecia and congenital/hereditary fibrosis. CLINICAL SUMMARY: A 12-year-old, male castrated chihuahua-mix dog was evaluated for skin lesions of unknown duration. The dog had severe alopecia, skin thickening and marked peripheral lymphadenopathy. Lymph node cytological investigation, immunohistochemical investigation and clonality testing demonstrated an intermediate to large B-cell lymphoma. The thickened skin had severe collagen deposition, effacing adnexal structures. The dog's lymphoma was treated but the skin lesions remained unchanged. The dog was euthanized. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first report of multicentric B-cell lymphoma in a dog with concurrent diffuse cutaneous sclerosis, similar to a human paraneoplastic reaction.

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.

Open trial of Bruton's tyrosine kinase inhibitor (PRN1008) in the treatment of canine pemphigus foliaceus.

BACKGROUND: Bruton's tyrosine kinase (BTK) is important in B-cell signalling. Efficacy has been reported for BTK inhibitors (BTKi) in human autoimmune diseases. Canine pemphigus foliaceus (cPF) is one of the most common canine autoimmune skin diseases. OBJECTIVES: To determine the safety and efficacy of the BTKi PRN1008 in the treatment of cPF. ANIMALS: Four privately owned dogs. METHODS AND MATERIALS: Four dogs diagnosed with PF were administered BTKi PRN1008. Initial dosages approximated to 15 mg/kg once daily, increased to twice daily if inadequate response was seen. Treatment continued for 20 weeks, attempting to decrease to every other day. Dogs were monitored with complete blood counts, serum biochemistry panels and urinalyses, and evaluated with a modified version of a validated human Pemphigus Disease Activity Index (cPDAI). Serum anti-desmocollin-1 (DSC-1) and desmoglein-1 (DSG-1) immunoglobulin (Ig)G titres were performed before and after the treatment period. Drug bound to target was measured in peripheral blood mononuclear cells (PBMC). RESULTS: All four dogs showed reduction in lesions and cPDAI score during the first two weeks of treatment. Three dogs continued to improve and sustained near complete remission by 20 weeks, at which point three responses were considered "good" and one "fair". Final daily dosages were in the range 17-33 mg/kg. Anti-DSC-1 IgG titre decreased dramatically in one dog, was undetectable in two and was uninterpretable in one dog. No dogs had detectable IgG to DSG1. A possible adverse event occurred in one dog. CONCLUSIONS AND CLINICAL IMPORTANCE: BTKi PRN1008 monotherapy may have some beneficial effects in some cases of cPF.

Efficacy of a Bruton's Tyrosine Kinase Inhibitor (PRN-473) in the treatment of canine pemphigus foliaceus.

BACKGROUND: Bruton's tyrosine kinase (BTK) is important in B-cell signalling. Efficacy has been reported for BTK inhibitors (BTKi) in human autoimmune diseases. Canine pemphigus foliaceus (cPF) is the most common canine autoimmune skin disease. OBJECTIVES: To determine the safety and efficacy of a BTKi in cPF treatment. ANIMALS: Nine privately owned dogs. METHODS AND MATERIALS: Nine dogs diagnosed with PF were administered BTKi PRN473. Initial dosages were ≈15 mg/kg once daily, increased to twice daily if inadequate response was seen. Treatment continued for a maximum of 20 weeks, attempting decrease to every other day. Dogs were monitored with complete blood counts, serum biochemistry panels, urinalyses and evaluated with a modified version of a validated human Pemphigus Disease Activity Index (cPDAI). Anti-desmocollin-1 (DSC-1) and desmoglein-1 (DSG-1) immunoglobulin G (IgG) titres were performed before and after the treatment period. Drug bound to target was measured in peripheral blood mononuclear cells. RESULTS: All nine dogs showed reduction in lesions and cPDAI score during the first two weeks of treatment. At the end of the study, four responses were considered "good", two "fair", two "poor" and one dog withdrawn due to recurrence of a previously excised mast cell tumour. Four dogs continued to improve by Week 4; three sustained near complete remission by study's end. The anti-DSC-1 IgG titre decreased in three dogs, increased in two, was undetected in three and was not performed in the withdrawn dog. No dogs had detectable IgG to DSG1. Possible adverse effects occurred in three dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Bruton's tyrosine kinase inhibitor monotherapy may have beneficial effects in some cases of cPF.

Clinicopathological findings and clinical outcomes in 49 cases of feline pemphigus foliaceus examined in Northern California, USA (1987-2017).

BACKGROUND: Few studies have described the pathophysiology, clinical course, treatment outcomes and quality of life (QoL) of cats with pemphigus foliaceus (PF). OBJECTIVE: Describe clinicopathological features, treatment outcomes and impacts on QoL in feline PF. ANIMALS: Forty-nine client-owned cats with PF that presented to a veterinary teaching hospital between 1987 and 2017. METHODS AND MATERIALS: Medical records and histopathological reports were reviewed to obtain clinicopathological data and treatment outcomes. Owners were contacted and requested to complete a questionnaire to obtain long-term follow-up and evaluate the impacts of PF on QoL of cats and owners. RESULTS: Domestic short/medium/long hair breeds were most commonly affected, with pinnae, head, haired face, nasal planum and ungual folds most frequently involved. Associated pruritus and systemic signs of illness were common. Vasculopathological changes were noted in a small proportion of cats. Corticosteroid monotherapy was sufficient to induce complete remission in the majority of cats. Pemphigus foliaceus and its management had a negative impact on QoL of both cats and owners. Receiving/administering medications, attending veterinary appointments, and financial and time commitments were cited sources of stress for affected cats and/or owners. CONCLUSIONS AND CLINICAL IMPORTANCE: Results illustrate that affected cats generally respond favourably to treatment but do require long-term therapy. The exact aetiology of the vasculopathological changes was unclear; it may reflect the stage or severity of disease or suggest the presence of a cutaneous adverse drug reaction. Clinicians managing cats with PF should be aware of the potential negative impact on QoL of owners and cats and adjust management accordingly.

Canine demodicosis: a retrospective study of a veterinary hospital population in California, USA (2000-2016).

BACKGROUND: Demodex spp. are cutaneous mites that cause clinical disease when present in increased numbers. There is an association in some dogs with underlying systemic disease or immunosuppressive medications. HYPOTHESIS/OBJECTIVES: Retrospective study to document breed predisposition, identify any concurrent diseases or underlying immunosuppressive conditions, and to determine the frequency of demodicosis recurrence after treatment completion. ANIMALS: There were 431 dogs with demodicosis presented to a veterinary teaching hospital in California, USA, from 2000 to 2016. METHODS: Inclusion in this study required a diagnosis of demodicosis based on direct demonstration of the mite. Records were reviewed for signalment, disease history, potential underlying aetiologies, diagnosed concurrent diseases, medications and demodicosis treatment. Analyses were performed to evaluate for potential breed predispositions and because of the large number of dogs with allergic dermatoses, analyses for this diagnosis as a disease associated with demodicosis was also performed. E-mailed surveys and follow-up telephone calls were used to assess for information about disease recurrence. RESULTS: The pit bull terrier group and West Highland white terrier, based on calculated odds ratio, were breeds predisposed to developing demodicosis. For dogs with demodicosis, allergic dermatoses was an associated disease. Relapse or recurrence of disease after treatment was uncommon, affecting 11% of the dogs with long-term follow-up. CONCLUSIONS/CLINICAL IMPORTANCE: This study identified, in dogs attending the institution based in California, USA, breed predilections for canine demodicosis and associated concomitant diseases. It also revealed a low occurrence of disease relapse, recurrence or persistence.

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.

Aspergillus otitis in small animals--a retrospective study of 17 cases.

BACKGROUND: Aspergillus spp. are saprophytic opportunistic fungal organisms and are a common cause of otomycosis in humans. Although there have been case reports of Aspergillus otitis externa in dogs, to the best of the authors' knowledge, this is the first retrospective case series describing Aspergillus otitis in dogs and cats. OBJECTIVE: To characterize signalment, putative risk factors, treatments and outcomes of a case series of dogs and cats with Aspergillus otitis. ANIMALS: Eight dogs and nine cats diagnosed with Aspergillus otitis. METHODS: A retrospective review of medical records from 1989 to 2014 identified animals diagnosed with Aspergillus otitis based on culture. RESULTS: All dogs weighed greater than 23 kg. The most common putative risk factors identified in this study were concurrent diseases, therapy causing immunosuppression or a history of an otic foreign body. Aspergillus otitis was unilateral in all study dogs and most cats. Concurrent otitis media was confirmed in three dogs and one cat, and suspected in two additional cats. Aspergillus fumigatus was the most common isolate overall and was the dominant isolate in cats. Aspergillus niger and A. terreus were more commonly isolated from dogs. Animals received various topical and systemic antifungal medications; however, otic lavage under anaesthesia and/or surgical intervention increased the likelihood of resolution of the fungal infection. CONCLUSION: Aspergillus otitis is uncommon, typically seen as unilateral otitis externa in cats and larger breed dogs with possible risk factors that include immunosuppression and otic foreign bodies; previous antibiotic usage was common.

Alopecia universalis in a dog with testicular neoplasia.

OBJECTIVE: To describe a case of testicular neoplasia and alopecia universalis in a dog, and successful treatment of the latter with ciclosporin. ANIMAL: Twelve-year-old intact male wirehaired fox terrier. METHODS: Castration, skin biopsy for histopathology, lymphocyte immunophenotyping and clonality analysis of the canine T-cell receptor gamma locus (TCRγ) rearrangement. RESULTS: The dog presented with symmetrical generalized alopecia. Testicular enlargement was noted which on castration was determined to be caused by bilateral interstitial cell tumours, Sertoli cell tumours and a unilateral seminoma. During the four months after castration the alopecia became more severe and widespread. Histopathology of the skin showed moderate, multifocal, mural folliculitis, peribulbar mucinosis and lymphocytic bulbitis, and targeting of anagen hair follicles. Immunophenotyping of the infiltrate showed a population of well-differentiated, small CD3-positive T lymphocytes, some expressing CD4 and others CD8. Molecular analysis revealed a polyclonal lymphocytic infiltrate, substantiating the diagnosis of alopecia areata rather than lymphoma. Treatment with ciclosporin (4.6 mg/kg) and ketoconazole (4.6 mg/kg) resulted in complete hair regrowth. CONCLUSION AND CLINICAL IMPORTANCE: Ciclosporin treatment, in combination with ketoconazole, can be effective for treatment of alopecia universalis in the dog. Alopecia universalis may present with clinically noninflammatory, symmetrical, generalized alopecia, mimicking an endocrine alopecia, and skin biopsies are needed to confirm the diagnosis.

A retrospective review of hyperaesthetic leucotrichia in horses in the USA.

BACKGROUND: Hyperaesthetic leucotrichia (HL) rarely affects horses and causes painful lesions on the dorsum that result in leucotrichia. This may be a variant of erythema multiforme (EM), but there are no studies investigating this condition. OBJECTIVES: Describe the clinical and histological features of HL and compare them to the histological features of EM. METHODS: A retrospective review of medical records from 1985 to 2015 identified 15 horses with HL. Thirteen biopsies of HL and five of EM were evaluated and compared. RESULTS: Arabian horses and their crosses (χ(2) (1)  = 8.56, P < 0.01) and American paint horses (χ(2) (1)  = 6.64, P < 0.05) were over represented. The onset of clinical signs was between April and September (14 of 15). The most common clinical signs were pain (15 of 15), leucotrichia (11 of 15), crusting (10 of 15) and alopecia (8 of 15) limited to darkly pigmented skin. The lesions recurred seasonally in 6 of 12 horses and unpredictably in 1 of 12 horse. The most common histological features were the presence of large stellate cells (13 of 13) and oedema (12 of 13) in the superficial dermis, perivascular to diffuse lymphocytic inflammation (13 of 13), pigmentary incontinence (12 of 13), apoptotic keratinocytes (9 of 13) and vesicle formation (8 of 13). Horses with EM (n = 5) had significantly more acanthosis (z = -2.40, P < 0.02) and lymphocytic exocytosis (z = -3.1, P < 0.004), satellitosis (Fisher's exact P = 0.02) and inflammation (z = -2.91, P < 0.004). Horses with HL had significantly more pigmentary incontinence (z = 2.13, P < 0.04) and superficial dermal oedema (z = 2.56, P < 0.002). CONCLUSIONS: HL affects primarily Arabian horses and American paint horses. It occurs mainly in summer and may recur. Histologically HL shares features with EM, but there are significant differences between them.

Localized parakeratotic hyperkeratosis in sixteen Boston terrier dogs.

BACKGROUND: Although zinc responsive dermatosis is typically a disorder of Arctic breed dogs, this study identifies similar cutaneous lesions on the face and pressure points of Boston terrier dogs. HYPOTHESIS/OBJECTIVES: To document the clinical and histological features of localized parakeratotic hyperkeratosis of Boston terrier dogs, to determine if the lesions respond to zinc supplementation and to determine whether tissue zinc levels were decreased in affected versus unaffected dogs. MATERIAL AND METHODS: Sixteen Boston terrier dogs with similar gross and histological findings were identified retrospectively from two institutions. Follow-up information for nine dogs from one institution was obtained from referring veterinarians using a questionnaire. Tissue zinc levels were measured from formalin-fixed paraffin-embedded skin biopsy samples of affected and unaffected dogs using inductively coupled plasma mass spectrometry. RESULTS: Mild to severe parakeratotic hyperkeratosis with follicular involvement was present in all 16 cases. Of the nine dogs for which follow-up information was available, five dogs received oral zinc supplementation and four dogs had documented clinical improvement or resolution of dermatological lesions. The median skin zinc levels were not significantly different between affected and unaffected dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge this is the first report of localized parakeratotic hyperkeratosis in Boston terrier dogs, some of which improved with oral zinc supplementation. Prospective studies in Boston terrier dogs are warranted to document potential zinc deficiency (serum and/or tissue levels, pre- and post-treatment) and to objectively assess response to zinc supplementation and other therapies.

Canine sterile nodular panniculitis: a retrospective study of 39 dogs.

BACKGROUND: Canine sterile nodular panniculitis (SNP) is an inflammatory disease of the panniculus that is typically managed with immunomodulatory or immunosuppressive treatments. It has been reported to be a cutaneous marker of an underlying systemic disease. HYPOTHESIS/OBJECTIVES: To assess the presence or absence of concurrent systemic diseases associated with canine SNP and to document breed predispositions. ANIMALS: Thirty nine dogs presented to a veterinary teaching hospital from 1990 to 2012 which met inclusion criteria. METHODS: Inclusion in this retrospective study required a diagnosis of SNP via histopathological analysis and negative special stains for infectious organisms. Breed distributions of affected dogs were compared to all other dogs examined at this hospital during the study period. Correlations between the histological pattern of panniculitis and the histological presence of dermatitis, clinical presentation of lesions, dog breed and therapeutic outcomes were assessed. RESULTS: Australian shepherd dogs, Brittany spaniels, Dalmatians, Pomeranians and Chihuahuas were significantly over-represented, but correlations between inflammatory patterns of panniculitis and other histological and clinical factors were not identified. Based on the information available in medical records, 32 dogs (82.1%) had no concurrent systemic diseases identified. Four dogs had concurrent polyarthritis, which may be related to SNP through unknown mechanisms. CONCLUSIONS/CLINICAL IMPORTANCE: This study identified several novel breed predilections for SNP; it failed to find any clear correlations with associated systemic diseases other than polyarthritis. The histological inflammatory pattern of SNP does not predict therapeutic outcome.

An exon 53 frameshift mutation in CUBN abrogates cubam function and causes Imerslund-Gräsbeck syndrome in dogs.

Cobalamin malabsorption accompanied by selective proteinuria is an autosomal recessive disorder known as Imerslund-Gräsbeck syndrome in humans and was previously described in dogs due to amnionless (AMN) mutations. The resultant vitamin B12 deficiency causes dyshematopoiesis, lethargy, failure to thrive, and life-threatening metabolic disruption in the juvenile period. We studied 3 kindreds of border collies with cobalamin malabsorption and mapped the disease locus in affected dogs to a 2.9Mb region of homozygosity on canine chromosome 2. The region included CUBN, the locus encoding cubilin, a peripheral membrane protein that in concert with AMN forms the functional intrinsic factor-cobalamin receptor expressed in ileum and a multi-ligand receptor in renal proximal tubules. Cobalamin malabsorption and proteinuria comprising CUBN ligands were demonstrated by radiolabeled cobalamin uptake studies and SDS-PAGE, respectively. CUBN mRNA and protein expression were reduced ~10 fold and ~20 fold, respectively, in both ileum and kidney of affected dogs. DNA sequencing demonstrated a single base deletion in exon 53 predicting a translational frameshift and early termination codon likely triggering nonsense mediated mRNA decay. The mutant allele segregated with the disease in the border collie kindred. The border collie disorder indicates that a CUBN mutation far C-terminal from the intrinsic factor-cobalamin binding site can abrogate receptor expression and cause Imerslund-Gräsbeck syndrome.

Prevalence of and risk factors for isolation of meticillin-resistant Staphylococcus spp. from dogs with pyoderma in northern California, USA.

BACKGROUND: Canine pyodermas associated with meticillin-resistant Staphylococcus spp. (MRS) have increased in prevalence over the past decade. HYPOTHESIS/OBJECTIVES: To compare the prevalence of MRS isolation from dogs with superficial pyoderma at a primary care clinic (PCC) and those at a tertiary care facility (VMTH) in California, USA, and identify associated risk factors. ANIMALS: Client-owned dogs from the VMTH (80 dogs) and the PCC (30 dogs). METHODS: Aerobic bacterial culture and antibiotic susceptibility were performed on swab specimens collected from dogs, and meticillin resistance was determined using microdilution methods according to Clinical and Laboratory Standards Institute guidelines. A mecA gene PCR assay was used to confirm meticillin resistance when possible. RESULTS: Of 89 staphylococcal isolates from the VMTH, 34 (38.2%) were meticillin resistant. In 31 dogs, pyoderma persisted, and one or more follow-up isolates were obtained. The species isolated and drug susceptibility changed unpredictably during treatment. Of 33 PCC isolates, nine (27.3%) were meticillin resistant. Multiple drug resistance was identified in 41 of 53 (77.3%) MRS isolates from the VMTH and five of nine from the PCC. The sensitivity and specificity of PCR for the detection of meticillin resistance was 34 of 39 (87%) and 86 of 87 (99%), respectively. Risk factors for meticillin resistance for both sites were antibiotic treatment within the last year (P = 0.001), and for VMTH, hospitalization of dogs within the last year (P = 0.001). CONCLUSIONS AND CLINICAL IMPORTANCE: The prevalence of meticillin resistance was not different between VMTH and PCC isolates (P = 0.29). Previous antimicrobial therapy was an important risk factor for the isolation of MRS at both sites.

Equine alopecia areata: a retrospective clinical descriptive study at the University of California, Davis (1980-2011).

BACKGROUND: Alopecia areata (AA) causes hair loss due to inflammatory changes within and around hair bulbs and lower portions of the hair follicles. Documentation of AA in horses is limited to a few case reports. HYPOTHESIS/OBJECTIVES: The aim of this retrospective study was to characterize equine AA by describing patterns in age, sex, breed and lesion distribution in a series of cases. An attempt was made to characterize the long-term course of the disease by surveying owners of affected horses. ANIMALS: Computerized records from 1 January 1980 to 1 July 2011 yielded 15 horses. METHODS: Descriptive statistics were calculated for age at presentation, breed, sex, dermatological signs, season when diagnosed and any recurrence of AA. The breed and sex distribution of horses with AA was compared with the equine hospital population during the study period. RESULTS: The prevalence of AA was 0.017%. Appaloosas and quarter horses were the most commonly recorded breeds. The median age was 9 years, with an age range from 3 to 15 years. Alopecia was the primary dermatological abnormality in all horses and commonly affected the mane, tail and face. More than half of the horses presented for other medical conditions. Five of seven (71.4%) owners who returned completed surveys reported a seasonal pattern to the disease, which usually worsened in spring and summer. CONCLUSIONS AND CLINICAL IMPORTANCE: Alopecia areata is a rare disease in horses, and is typically cosmetic in nature. To the authors' knowledge, this is the first study investigating the epidemiology of equine AA.