Intracranial epidermoid cyst in a cat / Cisto epidermoide intracraniano em um gato

Epidermoid cysts, also known as epidermal and keratin cysts, or congenital cholesteatomas are benign congenital non-neoplastic tumors, rarely observed in the brain of humans and some animal species (dogs, horses, mice, and rats). Histologically, they are composed of laminated, concentrically arranged keratin surrounded by a thin layer of stratified squamous epithelium. We describe a case of intracranial epidermoid cyst in a 6-year-old mixed-breed male cat in southern Brazil. The patient presented central vestibular syndrome. Given the poor prognosis and the fact that it belonged to a shelter with many dogs and cats, the owner requested euthanasia, and a thorough post-mortem examination was conducted immediately after death. The definitive diagnosis was based on histopathological findings. To the best of our knowledge, this is the first report of an intracranial epidermoid cyst in a cat.(AU)

Cisto epidermoide, também denominado cisto epidermal, cisto de queratina ou colesteatoma congênito é um tumor não neoplásico, benigno e congênito raramente encontrado no encéfalo de humanos e de algumas poucas espécies animais (cães, equinos, camundongos e ratos). Histologicamente, esse tumor é composto por queratina laminada concentricamente arranjada e circundada por uma fina parede de epitélio escamoso estratificado. Descreve-se um caso de cisto epidermoide intracraniano em um gato, macho, sem raça definida, de seis anos de idade, no sul do Brasil. O paciente foi encaminhado para atendimento veterinário por apresentar sinais de síndrome vestibular central. Devido ao mau prognóstico e por pertencer a um abrigo com muitos cães e gatos, o proprietário optou pela eutanásia e o paciente foi encaminhado para a realização de necropsia. O diagnóstico definitivo foi baseado nos achados histopatológicos. Pelo conhecimento dos autores, este é o primeiro relato de um cisto epidermoide intracraniano em um gato.(AU)

Segmental enteritis associated with Pythium insidiosum infection in a horse

Background: Pythiosis is an infectious disease caused by the oomycete Pythium insidiosum, with higher occurrence in wetlands and hot climate regions. This microorganism develops its cycle in aquatic plants, and most cases happen because of the contact of animals or people with water containing the motile zoospores (infectious form). Horses are the principal species affected and develop principally cutaneous and subcutaneous lesions, but the gastrointestinal tract is seldom affected. Humans develop various forms of pythiosis, such as a vascular form. The objectives of the current study are to describe an unusual case of intestinal pythiosis, its clinical signs, aspects of pathogenesis, and diagnosis. Case: A 13-year-old Crioula mare, from Santa Maria, RS, Brazil, presented with reduced food and water intake, apathy, restlessness, rolling, nasal reflux, firm abdomen upon palpation, and tachypnea during 2 days. The horses of this farm were fed native pasture and horse feed, and they had access to a nearby pond. Two days following the start of the clinical signs, the horse died and was necropsied on the farm. During necropsy, there was around 400 mL of reddish effusion in the abdominal cavity (modified transudate). A 15 cm segment of jejunum was firm upon palpation and had a severe transmural thickening. The wall of the affected area was up to 3 cm in thickness and firm, with small yellowish and irregular masses that stood out and looked friable, interpreted as kunkers. Microscopically, the yellowish masses (kunkers) were characterized by dense accumulations of intact and degenerate eosinophils (eosinophilic necrosis). Within these kunkers, and also on their periphery, there were multiple negatively stained hyphal profiles. Hyphae were also seen on the wall of small arteries inside the kunkers. These hyphae had nearly parallel walls and were occasionally...

Segmental enteritis associated with Pythium insidiosum infection in a horse

Background: Pythiosis is an infectious disease caused by the oomycete Pythium insidiosum, with higher occurrence in wetlands and hot climate regions. This microorganism develops its cycle in aquatic plants, and most cases happen because of the contact of animals or people with water containing the motile zoospores (infectious form). Horses are the principal species affected and develop principally cutaneous and subcutaneous lesions, but the gastrointestinal tract is seldom affected. Humans develop various forms of pythiosis, such as a vascular form. The objectives of the current study are to describe an unusual case of intestinal pythiosis, its clinical signs, aspects of pathogenesis, and diagnosis. Case: A 13-year-old Crioula mare, from Santa Maria, RS, Brazil, presented with reduced food and water intake, apathy, restlessness, rolling, nasal reflux, firm abdomen upon palpation, and tachypnea during 2 days. The horses of this farm were fed native pasture and horse feed, and they had access to a nearby pond. Two days following the start of the clinical signs, the horse died and was necropsied on the farm. During necropsy, there was around 400 mL of reddish effusion in the abdominal cavity (modified transudate). A 15 cm segment of jejunum was firm upon palpation and had a severe transmural thickening. The wall of the affected area was up to 3 cm in thickness and firm, with small yellowish and irregular masses that stood out and looked friable, interpreted as kunkers. Microscopically, the yellowish masses (kunkers) were characterized by dense accumulations of intact and degenerate eosinophils (eosinophilic necrosis). Within these kunkers, and also on their periphery, there were multiple negatively stained hyphal profiles. Hyphae were also seen on the wall of small arteries inside the kunkers. These hyphae had nearly parallel walls and were occasionally...(AU)

Aspectos anatomopatológicos do linfoma cutâneo em cães – revisão / Anatomopathological aspects of cutaneous lymphoma in dogs – review / Características histopatológicas del linfoma cutáneo en perros – revisión

O linfoma é um dos tipos de câncer mais prevalentes em cães, no entanto, aspectos macroscópicos, de lesões superficiais eritematosas e esfoliativas a tumores. é incomum na pele. Quando se origina na pele, tem sido observado sob vários Histologicamente, os linfomas cutâneos são subdivididos em epiteliotrópicos. Os linfomas epiteliotrópicos geralmente são vistos como micose fungoide e, mais raramente, como reticulose pagetoide ou síndrome de Sézary. Os linfomas não epiteliotrópicos incluem: linfoma anaplásico de grandes células T, linfoma de células T periféricas inespecífico, granulomatose linfomatoide, linfoma intravascular e linfoma de células T semelhante a paniculite subcutânea. Esta revisão de literatura apresenta os aspectos macroscópicos e histopatológicos dos linfomas cutâneos caninos.

Lymphoma is one of the most prevalent forms of cancers in dogs, however, it is uncommon on the skin. Cutaneous lymphoma can present as erythematous and exfoliative superficial lesions or raised masses. Histologically, cutaneous lymphomas are subdivided into epitheliotropic and non-epitheliotropic. Epitheliotropic lymphomas is mostly seen as mycosis fungoides and more rarely as pagetoid reticulosis or Sézary syndrome. Non-epitheliotropic lymphomas include anaplastic large T-cell lymphoma, unspecified peripheral T-cell lymphoma, lymphomatoid granulomatosis, intravascular lymphoma, and subcutaneous panniculitis-like T-cell lymphoma. This literature review presents macroscopic and histopathological aspects of canine cutaneous lymphomas.

El linfoma representa uno de los tipos de cáncer más prevalentes en perros, si bien su manifestación dérmica es poco frecuente. Los linfomas de piel pueden presentarse como lesiones superficiales eritematosas y exfoliativas, o bien como tumores. Desde el punto de vista histológico pueden ser clasificados como epiteliotrópicos y no epiteliotrópicos. Los primeros suelen ser vistos como micosis fúngica y, más raro, como reticulosis pagetoide o Síndrome de Sézary. Los linfomas no epiteliotrópicos incluyen el linfoma anaplásico de células T gigantes, linfoma inespecífico de células T, granulomatosis linfomatoide, linfoma intravascular y linfoma de células T similar a paniculitis subcutánea. Esta revisión de literatura presenta aspectos macroscópicos e histopatológicos de los linfomas cutáneos del perro.

Aspectos anatomopatológicos do linfoma cutâneo em cães revisão / Anatomopathological aspects of cutaneous lymphoma in dogs review / Características histopatológicas del linfoma cutáneo en perros revisión

O linfoma é um dos tipos de câncer mais prevalentes em cães, no entanto, aspectos macroscópicos, de lesões superficiais eritematosas e esfoliativas a tumores. é incomum na pele. Quando se origina na pele, tem sido observado sob vários Histologicamente, os linfomas cutâneos são subdivididos em epiteliotrópicos. Os linfomas epiteliotrópicos geralmente são vistos como micose fungoide e, mais raramente, como reticulose pagetoide ou síndrome de Sézary. Os linfomas não epiteliotrópicos incluem: linfoma anaplásico de grandes células T, linfoma de células T periféricas inespecífico, granulomatose linfomatoide, linfoma intravascular e linfoma de células T semelhante a paniculite subcutânea. Esta revisão de literatura apresenta os aspectos macroscópicos e histopatológicos dos linfomas cutâneos caninos.(AU)

Lymphoma is one of the most prevalent forms of cancers in dogs, however, it is uncommon on the skin. Cutaneous lymphoma can present as erythematous and exfoliative superficial lesions or raised masses. Histologically, cutaneous lymphomas are subdivided into epitheliotropic and non-epitheliotropic. Epitheliotropic lymphomas is mostly seen as mycosis fungoides and more rarely as pagetoid reticulosis or Sézary syndrome. Non-epitheliotropic lymphomas include anaplastic large T-cell lymphoma, unspecified peripheral T-cell lymphoma, lymphomatoid granulomatosis, intravascular lymphoma, and subcutaneous panniculitis-like T-cell lymphoma. This literature review presents macroscopic and histopathological aspects of canine cutaneous lymphomas.(AU)

El linfoma representa uno de los tipos de cáncer más prevalentes en perros, si bien su manifestación dérmica es poco frecuente. Los linfomas de piel pueden presentarse como lesiones superficiales eritematosas y exfoliativas, o bien como tumores. Desde el punto de vista histológico pueden ser clasificados como epiteliotrópicos y no epiteliotrópicos. Los primeros suelen ser vistos como micosis fúngica y, más raro, como reticulosis pagetoide o Síndrome de Sézary. Los linfomas no epiteliotrópicos incluyen el linfoma anaplásico de células T gigantes, linfoma inespecífico de células T, granulomatosis linfomatoide, linfoma intravascular y linfoma de células T similar a paniculitis subcutánea. Esta revisión de literatura presenta aspectos macroscópicos e histopatológicos de los linfomas cutáneos del perro.(AU)