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.

Bovine sarcocystosis: Sarcocystis species, diagnosis, prevalence, economic and public health considerations, and association of Sarcocystis species with eosinophilic myositis in cattle.

Infections by Sarcocystis in cattle are ubiquitous worldwide. There is considerable debate concerning the identity of Sarcocystis spp. in cattle. Proper diagnosis of Sarcocystis spp. is important to assess their economic and public health importance. Currently there are seven named species: Sarcocystis hirsuta, Sarcocystis cruzi, Sarcocystis hominis, Sarcocystis bovifelis, arcocystis heydorni, Sarcocystis bovini and Sarcocystis rommeli. Additionally, there are unnamed Sarcocystis spp. Two species, S. hominis and S. heydorni, are zoonotic. One out of seven species (S. hirsuta, contracted from cats) forms macroscopic cysts which can be visible during carcass inspection. Current molecular characterization is based on DNA extracted from sarcocysts from naturally infected cattle because DNA was not characterized from tissues of experimentally infected cattle or feces of experimentally infected definitive hosts. Sarcocystis cruzi (transmitted via canids) is recognized as the most pathogenic species and it causes abortion, low milk yield, poor body growth, and outbreaks of clinical sarcocystosis and death. Additionally, Sarcocystis infections have been linked to an inflammatory condition of striated muscles termed bovine eosinophilic myositis (BEM). Cattle affected by BEM appear clinically normal. Diagnosis of BEM at slaughter occurs when inspecting the carcass surface, or once the carcass has been divided into prime cuts or quarters. Sex and breed have no apparent influence on prevalence of BEM. The condition evidently occurs with equal frequency in steers, cows, and heifers. Virtually all striated muscles can be affected including skeletal muscles, the muscles of the eye, larynx, and the heart. In the USA, regulations require condemnation of BEM-affected parts, or (in severe cases) the entire carcass. These aesthetic considerations result in economic losses. Cattle experimentally infected with Sarcocystis did not have BEM at slaughter. Here, we review the status of Sarcocystis spp. and BEM in cattle including prevalence, lesions, epidemiology, and association of BEM with different species of Sarcocystis.

Molecular detection of Sarcocystis cruzi in three beef carcases with eosinophilic myositis lesions and in unaffected beef from animals in the same herd.

Eosinophilic myositis in bovine striated muscle thought to be caused by a hypersensitivity reaction to the degradation of Sarcocystis tissue cysts, is a rare reason for carcase condemnation in the United Kingdom. This paper describes the identification of Sarcocystis cruzi associated with lesions of generalised eosinophilic myositis in three English beef carcases, by gross and histopathological examination followed by PCR with subsequent sequencing. Samples from two unaffected animals were also examined. Although sarcocystosis caused by S.cruzi is not considered a public health risk, the clinically affected carcases were deemed unfit for human consumption due to the extensive lesions affecting meat quality. We believe this to be the first report from the UK describing the molecular-based identification of Sarcocystis cruzi in meat affected and unaffected with eosinophilic myositis.

Clinical characteristics of non-infectious inflammatory myopathy in the boxer dog.

OBJECTIVES: To evaluate the clinical characteristics, treatment, outcome and potential association between non-infectious inflammatory myopathy and malignancy in boxer dogs. MATERIALS AND METHODS: Boxer dogs histologically diagnosed with non-infectious inflammatory myopathy at the Comparative Neuromuscular Laboratory, University of California San Diego from 2010 to 2018 and with complete medical records were included in this retrospective study. Signalment, history, clinical signs, clinicopathologic findings, treatment and outcome were documented. RESULTS: Twenty-eight boxer dogs with non-infectious inflammatory myopathy, aged 1 to 11 years, were included. Eighteen were male (16 neutered; two entire) and 10 were female (seven spayed; three entire). Clinical signs included generalised weakness (n=17), dysphagia (n=11) and weight loss (n=10). Serum creatine kinase activity was elevated in all 20 cases tested (range 908 to 138,000 IU/L). One dog had undifferentiated round cell neoplastic infiltration within the muscle at the time of inflammatory myopathy diagnosis. Five dogs historically had mast cell tumours and 21 dogs were not diagnosed with neoplasia prior, at the time of or after inflammatory myopathy diagnosis. Treatment included glucocorticoid monotherapy (n=12), cyclosporine monotherapy (n=1) or multiple immune-suppressive medications (n=14). Six dogs neurologically improved, 11 improved but relapsed while on treatment, seven did not improve. Eight dogs were euthanased, one died, four were lost to follow-up. CLINICAL SIGNIFICANCE: Boxer dogs with non-infectious inflammatory myopathy can present for generalised weakness and dysphagia; long-term successful outcome is uncommon. The relationship between neoplasia and non-infectious inflammatory myopathy in boxer dogs remains unclear; future prospective studies evaluating a larger cohort are warranted.

Punica granatum and amygdalin extracts plus cobalamin combined with albendazole reduce larval burden and myositis in experimental trichinosis / Extratos de Punica granatum e amígdalina mais cobalamina combinado com albendazol reduzem a carga larvar e a miosite na triquinose experimental

Abstract Trichinellosis is a zoonosis results from eating raw or semi-cooked meat of infected animals. Medicinal plants have been used lately as alternatives and/or combined therapies to resolve some drawbacks of the current regimens. This work analyzed the effect of albendazole monotherapy on Trichinella spiralis experimental infection (group A), in comparison to P. granatum and amygdalin extracts +cobalamin (group B), plus its combination with albendazole (group C). The study revealed that the extracts alone or combined with albendazole had an inferior effect to albendazole monotherapy regarding number of adult worms (40.83 ±3.82, 18.67 ±1.86 and 16.83 ±2.32, respectively). However, their effect was more obvious in muscle phase combined with albendazole, achieving the lower number of larvae/mL tissue homogenate (22.33 ±3.27 in comparison to 39.67 ±2.58 achieved by albendazole monotherapy). The extracts exerted a significant immunomodulatory effect by reducing the local CD4+ expression in the intestine as well as in muscle phase (1.15 ±0.25 and 3.80 ±0.65 in comparison to 4.97 ±0.37 and 12.20 ±0.87 with albendazole monotherapy, respectively). So, these extracts improved the therapeutic efficacy of albendazole, specifically in muscle phase and counteracted the inflammatory reaction caused by albendazole monotherapy, thus extensively alleviating the resulting myositis.

Resumo Trichinellosis é uma zoonose resultante da ingestão de carne crua ou semicozida de animais infectados. As plantas medicinais têm sido usadas, ultimamente, como alternativas e/ou terapias combinadas, para resolver algumas desvantagens dos regimes atuais. Este trabalho analisou o efeito da monoterapia albendazole na infecção experimental por Trichinella spiralis (grupo A), em comparação com extratos de P. granatum e amígdalina +cobalamina (grupo B), além de sua combinação com albendazol (grupo C). O estudo revelou que os extratos sozinho ou combinado com albendazol teve efeito inferior à monoterapia albendazol em relação ao número de vermes adultos (40,83 ±3,82, 18,67 ±1,86 e 16,83 ±2,32, respectivamente). No entanto, seu efeito foi mais óbvio na fase muscular combinado com o albendazol, alcançando o menor número de larvas/mL homogeneizado de tecido (22,33 ±3,27 em comparação com 39,67 ±2,58 obtidos pela monoterapia albendazol). Os extratos exerceram um efeito imunomodulatório significativo, ao reduzir a expressão local CD4+ no intestino, bem como na fase muscular (1,15 ±0,25 e 3,80 ±0,65 em comparação com 4,97 ±0,37 e 12,20 ±0,87 com monoterapia albendazol, respectivamente). Assim, esses extratos melhoraram a eficácia terapêutica do albendazol, especificamente na fase muscular e neutralizaram a reação inflamatória causada pela monoterapia albendazol, aliviando extensivamente a miosite resultante.

Sarcocystis gigantea infection associated with granulomatous eosinophilic myositis in a horse.

The only Sarcocystis species currently known to inhabit the fibers of skeletal and cardiac muscles in horses are S. fayeri, S. bertrami, and S. asinus. We describe herein the invasion of myofibers in a horse by S. gigantea, a sheep-specific species with low virulence in the original host. A hunter gelding was referred to a veterinary surgeon in Newmarket (UK). The anamnestic data reported that the horse had an initial history of swelling of the right forelimb with fluid on the front of the carpus and edema spreading up the forearm. Subsequently, 2 firm lumps were found on the left pectoral muscle adjacent to the axilla of the left forelimb. Histologic examination of biopsies from the lumps revealed multifocal granulomatous eosinophilic myositis associated with intact and degenerate encysted parasites, consistent with Sarcocystis spp. Based on amplification and DNA sequencing of the 18S rRNA gene obtained from formalin-fixed, paraffin-embedded tissue blocks, S. gigantea was identified. The presence of sarcocysts in equine skeletal muscles has been considered an incidental finding, and there are only sporadic associated reports of myositis. Our finding suggests that some Sarcocystis spp. have a wider intermediate host range than believed previously, and that Sarcocystis of other species (not considered horse-associated) can invade the muscle fibers of equids, leading to myositis.

Muscular Sarcocystosis in Sheep Associated With Lymphoplasmacytic Myositis and Expression of Major Histocompatibility Complex Class I and II.

Sarcocystosis is a protozoal disease affecting a wide range of animals. The aims of this study were to characterize the following in sheep: (1) the muscle pathology in Sarcocystis infection, (2) the inflammatory infiltrate and its relationship to severity of infection, and (3) immune markers expressed by parasitized muscle fibers and parasitic cysts. Skeletal muscle samples from 78 sheep slaughtered in southern Italy were snap frozen and analyzed by histopathology, immunohistochemistry, and immunofluorescence. Polymerase chain reaction (PCR) and sequencing were used for Sarcocystis species identification. All 40 muscle samples tested were PCR-positive for Sarcocystis tenella. Histologically, cysts were identified in 76/78 cases (97%), associated with an endomysial infiltrate of lymphocytes and plasma cells. The T cells were predominantly CD8+, with fewer CD4+ or CD79α+ cells. Eosinophils were absent. Notably, sarcolemmal immunopositivity for major histocompatibility complex (MHC) I and II was found in 76/78 cases (97%) and 75/78 cases (96%), respectively, both in samples with and in those without evident inflammatory infiltrate. The number of cysts was positively correlated with inflammation. In addition, MHC I was detected in 55/78 cyst walls (72%), and occasionally co-localized with the membrane-associated protein dystrophin. The findings suggest that muscle fibers respond to the presence of cysts by expression of MHC I and II. The possible role of MHC I and II in the inflammatory response and on the cyst wall is also discussed.

Polyphasic Rhabdomyositis in California Sea Lions (Zalophus Californianus): Pathology and Potential Causes.

A myositis syndrome has been recognized for more than a decade in California sea lions (CSLs; Zalophus californianus) but a detailed description of the lesions and potential causes of this condition is lacking. The tissues of 136 stranded CSLs with rhabdomyositis were examined. Rhabdomyositis was considered incidental in 67% (91/136) of the CSLs, and a factor contributing to the animal stranding (significant rhabdomyositis) in 33% (45/136). Of the 91 cases with incidental rhabdomyositis, lesions consisted of a few small foci of lymphohistiocytic inflammation. Of the 45 cases with significant rhabdomyositis, 28 (62%) also presented with major comorbidities such as leptospirosis (2 animals) and domoic acid toxicosis (6 animals), whereas 17 (38%) had severe polyphasic rhabdomyositis as the only major disease process associated with mortality. In these animals, most striated muscles had multiple white streaks and diffuse atrophy. Microscopically, there was myofiber necrosis surrounded by lymphocytes and histiocytes admixed with areas of myofiber regeneration, and/or moderate to severe rhabdomyocyte atrophy usually adjacent to intact Sarcocystis neurona cysts. At the interface of affected and normal muscle, occasional T lymphocytes infiltrated the sarcoplasm of intact myocytes, and occasional myofibers expressed MHCII proteins in the sarcoplasm. S. neurona antibody titers and cyst burden were higher in animals with significant polymyositis antibody titers of (26125 ± 2164, 4.5 ± 1.2 cysts per section) and active myonecrosis than animals with incidental rhabdomyositis antibody titers of (7612 ± 1042, 1.7 ± 0.82 cysts per section). The presented findings suggest that S. neurona infection and immune-mediated mechanisms could be associated with significant polyphasic rhabdomyositis in CSLs.

Blackleg in a free-range brown brocket deer (Mazama gouazoubira) / Carbúnculo sintomático em veado virá de vida livre (Mazama gouazoubira)

A case of blackleg in a brown brocket deer (Mazama gouazoubira) associated with trauma from being hit by a car in southern Rio Grande do Sul is reported. The clinical signs included fever, dehydration and lethargy that worsened progressively until 36 hours after the accident, when the animal died. In the fore right limb, there was a comminuted closed fracture of the radius and ulna but no skin wounds were observed. Grossly, the musculature of the pelvic limbs presented hemorrhage, edema and emphysema. Microscopically, the muscles of both rear legs had necrosis, edema, hemorrhage and mild inflammatory infiltration of neutrophils. Clostridium chauvoei was cultured from affected skeletal muscles, and it was also detected by immunohistochemistry, confirming a diagnosis of blackleg. The overlapping habitat of cattle and brown brocket deer is proposed as a predisposing factor in this case and alerts to spillover cases maybe happening in this region. In addition, blackleg should be included as differential diagnoses of deer with post-traumatic myositis.(AU)

Descreve-se um caso de carbúnculo sintomático em um veado-virá (Mazama gouazoubira), macho, jovem, resgatado após atropelamento em uma rodovia na região sul do Rio Grande do Sul. O cervídeo apresentou febre, desidratação e letargia, progredindo para a morte em 36 horas. No membro torácico direito foi observado fratura cominutiva fechada de rádio e ulna sem a presença de feridas perfurantes. Na necropsia foi observada hemorragia, edema e enfisema na musculatura dos membros pélvicos. Microscopicamente, os músculos dos membros pélvicos apresentaram necrose, edema, hemorragia e discreto infiltrado inflamatório neutrofílico. Houve o isolamento de Clostridium chauvoei e marcação positiva na técnica de IHQ com anticorpo monoclonal anti-C. chauvoei, confirmando o diagnóstico de carbúnculo sintomático. A sobreposição de habitat entre bovinos domésticos e cervídeos pode ser um fator de risco para esta doença e chama a atenção para casos de "spillover" que podem estar ocorrendo na região. Adicionalmente, sugere-se que o carbúnculo sintomático seja incluído nos diagnósticos diferenciais de cervídeos que apresentam miosite pós-traumática.(AU)

High prevalence of chigger mite infection in a forest-specialist frog with evidence of parasite-related granulomatous myositis.

Amphibians are hosts for a wide variety of micro- and macro-parasites. Chigger mites from the Hannemania genus are known to infect a wide variety of amphibian species across the Americas. In Chile, three species (H. pattoni, H. gonzaleacunae and H. ortizi) have been described infecting native anurans; however, neither impacts nor the microscopic lesions associated with these parasites have been described. Here, we document 70% prevalence of chigger mite infection in Eupsophus roseus and absence of infection in Rhinoderma darwinii in the Nahuelbuta Range, Chile. Additionally, we describe the macroscopic and microscopic lesions produced by H. ortizi in one of these species, documenting previously undescribed lesions (granulomatous myositis) within the host's musculature. These findings highlight that further research to better understand the impacts of chigger mite infection on amphibians is urgently required in Chile and elsewhere.

Blackleg in cattle in the state Mato Grosso do Sul, Brazil: 59 cases / Carbúnculo sintomático em bovinos em Mato Grosso do Sul: 59 casos

This study aimed to review cases of blackleg (Clostridium chauvoei infection) diagnosed in cattle from Midwestern Brazil from 1994 to 2014 considering epidemiological, clinical, necropsy and histopathological findings. Also the following laboratory tests were used for the diagnosis of some cases of blackleg: microbiological culture and identification of the agent, microbiological culture and identification of the agent by the polymerase chain reaction (PCR), and identification of the agent in formalin fixed paraffin embedded tissues (FFPE). Criteria for presumptive diagnosis of blackleg included necrohemorrhagic emphysematous myositis consisting of inflammatory infiltrate, coagulative necrosis of myofiber, interstitial edema, hemorrhage, and gas bubbles between myofibers. Fifty nine cases from 51 outbreaks of blackleg were found, which corresponded to 1.1% of 5,375 cattle deaths investigated. In five of those outbreaks, samples of affected muscles cultures for the identification of pathogenic clostridia were made. Another three samples of similar material were cultured for clostridia with subsequent identification of the isolate by PCR. Twelve samples of FFPE affected muscle fragments were submitted to PCR for identification of the etiological agent. Except for January, cases were observed in each month of the year, with higher numbers in July-October. Most affected cattle were in the age of 7-12 years, but calves younger than 6 month-old and older than 24 months were also observed. Vaccination histories were scarce. In 32 outbreaks some vaccination history was available, but only in two of those vaccination has been carried out properly. In 56 six cases the skeletal muscles were involved. Muscles of the hind limbs were the most affected. In ten cases muscles of the tongue, myocardium and diaphragm were also affected. In three of the cases the visceral form was observed. Deaths occurred after a clinical course of 6-24 hours, but in most cases cattle were found death. Sudden death was the outcome in visceral cases (cardiac) blackleg. Clostridium chauvoei was confirmed to be the cause by culturing in 5 cases, and by PCR and histopatology in 8 cases. Bacterial culture followed by PCR did not demonstrate C. chauvoei. Calculation of the economic impact indicates that blackleg is a frequent disease in the state of Mato Grosso do Sul (MS) that inflicts significant economic loss. The amount of these losses would be reduced through proper vaccination programs against the prevalent strains of C. chauvoei in the region.(AU)

Este estudo foi realizado com o objetivo de descrever casos de carbúnculo sintomático (infecção por Clostridium chauvoei) diagnosticados em bovinos do Centro-Oeste brasileiro de 1994-2014, avaliando a epidemiologia, os sinais clínicos, os achados de necropsia e a histopatologia; objetivou-se também avaliar os seguintes testes laboratoriais para o diagnóstico de carbúnculo sintomático: cultura microbiológica e identificação do agente, cultura microbiológica e identificação do agente por reação em cadeia de polimerase (PCR) e identificação do agente em material fixado em formol e incluído em parafina (FFIP). Os critérios para o diagnóstico presuntivo de carbúnculo sintomático incluíram miosite necro-hemorrágica enfisematosa, caracterizada por infiltrado inflamatório, necrose de coagulação de miofribras, edema intersticial, hemorragia e bolhas de gás em meio às miofribras. Cinquenta e nove casos oriundos de 51 surtos foram encontrados, o que corresponde a 1,1% das 5.375 mortes de bovinos investigadas. Em cinco desses casos, amostras do músculo afetado foram cultivadas para clostrídios patogênicos. Amostras semelhantes de outros três animais foram cultivadas para clostrídios e os isolamentos identificados subsequentes por PCR. Doze fragmentos de músculo afetado FFIP foram submetidos a PCR para identificação do agente etiológico. Com exceção de janeiro, os casos de carbúnculo sintomático foram observados em todos os meses do ano com uma maior incidência em junho-outubro. A faixa etária da maioria dos bovinos afetados era de 7-12 anos de idade, mas bovinos mais jovens que 6 meses e mais velhos que 24 meses foram também afetados. Os históricos de vacinação eram escassos nesses surtos. Em 32 surtos havia alguma informação sobre a vacinação, mas em apenas dois casos a vacinação tinha sido realizada adequadamente. Cinquenta e seis casos de carbúnculo sintomático deste estudo eram casos clássicos afetando os músculos esqueléticos. Os músculos mais afetados foram os dos membros pélvicos. Em dez casos os músculos da língua, miocárdio e diafragma estavam também afetados. Apenas três dos casos apresentaram a forma visceral (cardíaca). O curso clínico foi de 6-24 horas, mas na maioria dos casos os bovinos foram encontrados mortos. Em casos da forma visceral ocorria morte súbita. Clostridium chauvoei foi confirmado como o agente causal por cultura em cinco casos e por PCR em amostra FFIP em 8 casos. Cultura bacteriana seguida de PCR do isolado não demonstrou C. chauvoei. Carbúnculo sintomático é uma doença frequente em bovinos no Mato Grosso do Sul podendo provocar importantes prejuízos para os produtores rurais. Esses prejuízos podem ser reduzidos através de um programa de vacinação adequado usando-se vacinas eficazes contra cepas de C. chauvoei prevalentes na região.(AU)

Inflammatory Myopathy in Horses With Chronic Piroplasmosis.

Horses affected by chronic piroplasmosis may develop poor performance and muscle atrophy. Here we investigate the pathological and immunopathological aspects of myopathy occurring in chronic equine piroplasmosis. The study included 16 horses serologically positive for equine piroplasms presenting with clinical signs and supporting serum biochemical evidence of a myopathy. Skeletal muscle was evaluated by histopathology, immunohistochemistry, indirect immunofluorescence, and molecular detection of piroplasms and inflammatory cytokines in skeletal muscle. Histologic lesions included muscle fiber atrophy (100% of cases), degenerative changes (13/16, 81%), and perivascular perimysial and endomysial lymphocytic infiltrates (81% of cases). In 15 cases (94%), muscle fibers had strong immunostaining for major histocompatibility complex classes I and II. T lymphocyte populations were mainly CD3+, CD8+, and CD4+ in equal proportions, with a lower number of CD79α+ cells. The serum from affected horses was tested by indirect immunofluorescence for binding of IgG, IgM, or IgA to sections of normal equine muscle to detect circulating autoantibodies against muscle antigen(s). In all cases, distinct sarcolemmal staining was detected in sections incubated with serum from affected horses, in contrast to sections incubated with phosphate-buffered saline or equine control sera. Reverse transcription polymerase chain reaction (RT-PCR) testing of muscles from affected animals revealed a significant increase of interferon-γ, interleukin-12, and tumor necrosis factor-α gene expression compared to healthy controls. Theileria equi or Babesia caballi was not detected in samples of affected muscle by RT-PCR. Thus, inflammatory myopathy associated with equine piroplasmosis may involve an autoimmune pathogenesis with upregulation of inflammatory cytokines that may cause myofiber atrophy and degeneration.

Granulomatous Necrotizing Myositis in Swine Affected by Porcine Circovirus Disease.

Porcine circovirus type 2 (PCV2) is associated with multiple clinical syndromes in pigs, known as porcine circovirus diseases. This work describes an outbreak of porcine circovirus diseases with severe lesions affecting the skeletal muscle. Ninety-two pigs had apathy, weight loss, and diarrhea over a clinical course of 7 to 10 days. Approximately 30 of the pigs had stiff gait, muscle weakness, hind limb paresis, and recumbency. Twelve of the 92 pigs were necropsied, and 4 had pale discoloration of skeletal muscles with microscopic lesions of granulomatous necrotizing myositis. Immunohistochemistry of skeletal muscle showed that PCV2 antigen was located primarily in the cytoplasm and nuclei of macrophages, lymphocytes, and multinucleated giant cells, with a lower amount in the cytoplasm of endothelial cells, necrotic fibers, and satellite cells. Affected muscle samples were polymerase chain reaction-positive for PCV2 and the amplicon exhibited 99% identity with sequences belonging to the PCV2b genotype. Locomotor clinical signs and granulomatous necrotizing myositis should be considered as another expression of PCV2 infection in pigs.

Management of Orbital Diseases.

Orbital diseases are common in dogs and cats and can present on emergency due to the acute onset of many of these issues. The difficulty with diagnosis and therapy of orbital disease is that the location of the problem is not readily visible. The focus of this article is on recognizing classical clinical presentations of orbital disease, which are typically exophthalmos, strabismus, enophthalmos, proptosis, or intraconal swelling. After the orbital disease is confirmed, certain characteristics such as pain on opening the mouth, acute vs. chronic swelling, and involvement of nearby structures can be helpful in determining the underlying cause. Abscesses, cellulitis, sialoceles, neoplasia (primary or secondary), foreign bodies, and immune-mediated diseases can all lead to exophthalmos, but it can be difficult to determine the cause of disease without advanced diagnostic imaging, such as ultrasound, magnetic resonance imaging, or computed tomography scan. Fine-needle aspirates and biopsies of the retrobulbar space can also be performed.

Clinical features of idiopathic inflammatory polymyopathy in the Hungarian Vizsla.

BACKGROUND: A retrospective study of the clinicopathological features of presumed and confirmed cases of idiopathic inflammatory polymyopathy in the Hungarian Vizsla dog and guidelines for breeding. RESULTS: 369 medical records were reviewed (1992-2013) and 77 Hungarian Vizslas were identified with a case history consistent with idiopathic inflammatory polymyopathy. Inclusion criteria were: group 1 (confirmed diagnosis); histopathology and clinical findings compatible with an inflammatory polymyopathy and group 2 (probable diagnosis); clinical findings compatible with a polymyopathy including dysphagia, sialorrhea, temporal muscle atrophy, elevated serum creatine kinase (CK) activity, and sufficient clinical history to suggest that other neuromuscular disorders could be ruled out. Some group 2 dogs had muscle biopsy, which suggested muscle disease but did not reveal an inflammatory process. The mean age of onset was 2.4 years; male dogs were slightly overrepresented. Common presenting signs were dysphagia, sialorrhea, masticatory muscle atrophy, and regurgitation. Common muscle histopathological findings included degenerative and regenerative changes, with multifocal mononuclear cell infiltration with lymphoplasmacytic myositis of variable severity. A positive response to immunosuppressive treatment supported an immune-mediated aetiology. The mean age at death and survival time were 6.4 and 3.9 years, respectively. Recurrence of clinical signs and aspiration pneumonia were common reasons for euthanasia. CONCLUSIONS: Diagnosis of Vizsla idiopathic inflammatory polymyopathy can be challenging due to lack of specific tests, however the presence of dysphagia, regurgitation and masticatory muscle atrophy in this breed with negative serological tests for masticatory muscle myositis and myasthenia gravis, along with muscle biopsies suggesting an inflammatory process, support the diagnosis. However, there is an urgent need for a more specific diagnostic test. The average of inbreeding coefficient (CoI) of 16.3% suggests an increased expression of a Dog Leukocyte Antigen Class II haplotype, leading to an increased disease risk. The prognosis remains guarded, as treatment can only manage the disease. Recurrence of clinical signs and perceived poor quality of life are the most common reasons for humane euthanasia.

Dynamic exophthalmos and lateral strabismus in a dog caused by masticatory muscle myositis.

CASE DESCRIPTION: A 5.5-year-old neutered male mixed-breed dog was presented for evaluation of a 5-month history of deviation of the right globe upon opening the mouth and a 1-month history of conjunctivitis in the same eye. Clinical findings, diagnostic imaging results, treatment and follow-up are described. CLINICAL FINDINGS: When the mouth was opened, the right globe deviated rostrally and laterally. There was no pain or resistance to opening the mouth, or resistance to retropulsion of the globe. No other abnormalities were observed. Computed tomography was performed, revealing a contrast-enhancing region associated with the right masseter muscle impinging into the right orbit; this was more pronounced with the mouth open. Cytology revealed a small number of mildly to moderately atypical mesenchymal cells. Histopathology was consistent with polyphasic myositis, with a predominance of lymphocytes and plasma cells. No infectious agents were identified. Serum antibody titers for Toxoplasma gondii and Neospora caninum were negative. Serum titers for 2 M antibody were positive at 1:500, consistent with a diagnosis of masticatory muscle myositis. TREATMENT AND OUTCOME: Therapy with prednisone was initiated. During a follow-up period of 5 months, there was no recurrence of clinical signs, and the dose of prednisone was reduced by 25%. CLINICAL SIGNIFICANCE: To the authors' knowledge, this is the first reported case of masticatory muscle myositis causing dynamic exophthalmos and strabismus in a dog.

Acute myonecrosis in horse caused by Clostridium novyi type A.

The objective of this study was to describe the first report involving a case of equine acute myonecrosis caused by C. novyi type A with an emphasis on clinical signs, the pathological and bacteriological analysis, and molecular identification of the microorganisms as the key of the definitive diagnosis.

Acute myonecrosis in horse caused by Clostridium novyi type A

The objective of this study was to describe the first report involving a case of equine acute myonecrosis caused by C. novyi type A with an emphasis on clinical signs, the pathological and bacteriological analysis, and molecular identification of the microorganisms as the key of the definitive diagnosis.

Different Sarcocystis spp. are present in bovine eosinophilic myositis.

It has been suggested that Sarcocystis species are associated with bovine eosinophilic myositis (BEM). To date, parasite identification in this myopathy has been based on morphological techniques. The aim of the present study was to use molecular techniques to identify Sarcocystis species inside lesions of BEM. Histologically, BEM lesions of 97 condemned carcasses were examined for the presence of Sarcocystis species. Intralesional and extralesional cysts were collected using laser capture microdissection and the species was determined with a PCR-based technique based on 18S rDNA. Intralesional sarcocysts or remnants were found in BEM lesions in 28% of the carcasses. The majority (82%) of intralesional Sarcocystis species were found to be S. hominis. However S. cruzi and S. hirsuta were also found, as well as an unidentified species. It can be concluded that Sarcocystis species present in lesions of BEM are not restricted to one species.