Non-Renal Lesions of Uraemia in Domestic Cats.

Uraemia is a clinical syndrome caused by an increase in uraemia-associated toxins in the bloodstream as a consequence of intrinsic kidney or lower urinary tract diseases. Cats seem to be more affected by urinary tract diseases than dogs, particularly considering that chronic kidney disease (CKD) is one of the most important conditions in cats. Considering the lack of information on the systemic lesions of uraemia in cats, the aim of this study was to investigate the prevalence and clinical and pathological aspects of non-renal lesions in uraemic cats, with special attention to the differences between cats and dogs. Cats necropsied between 2000 and 2019 (n = 1,330) were investigated for urinary tract diseases and non-renal lesions of uraemia. The prevalence of uraemic cats with non-renal lesions (n = 78) was 5.8%. Adult, elderly and male animals were predominantly affected. Anorexia, apathy and vomiting were the most common clinical signs and CKD was observed in the majority of uraemic cats. Pulmonary oedema was the most frequent non-renal lesion identified. In contrast with previous reports, haemorrhagic and ulcerative gastritis was frequently observed, whereas soft tissue mineralization and parathyroid hyperplasia were uncommon features. Fibrous osteodystrophy was not observed. Cats with urinary tract diseases did not have as wide a variety of non-renal uraemic lesions as uraemic dogs and multisystemic manifestation of uraemia was observed in only 24.4% of cases.

Testicular tumors in 190 dogs: clinical, macroscopic and histopathological aspects / Neoplasmas testiculares em 190 cães: aspectos clínicos, macroscópicos e histopatológicos

This study aimed to characterize the prevalence and clinical, macroscopic and histopathological aspects of dogs affected by testicular tumors based on biopsy specimens from the Laboratório de Patologia Veterinária of the Universidade Federal de Santa Maria (LPV-UFSM) over 19 years. Parameters regarding the age, size, and breed of the affected dogs were also established. Of all dogs with some type of neoplasm submitted to histopathological analysis at the LPV over these 19 years (n=1,900), 213 (11.2%) had at least one testicular neoplasm. The tissues of 190 dogs (with 220 neoplasms) were available for histological reassessment. The dogs in this study had different types of testicular tumors with relatively similar frequencies. In descending order, the most frequent testicular neoplasms were seminomas (88/220), Leydig (interstitial) cell tumor (LCT; 64/220), Sertoli cell tumor (SCT; 61/220), and mixed germ cell-sex cord stromal tumor (MGSCT) (07/220). Among the dogs of defined breed (119 cases), large breeds had the largest number of cases (50/119), followed by small (47/119) and medium-sized (22/119) breeds. The ages of dogs affected by testicular tumors ranged from 10 months to 18 years. Increased testicular volume was the most common clinical manifestation. Eleven dogs presented information about clinical signs suggestive of hyperestrogenism syndrome (feminization). In seminomas, the diffuse pattern predominated over the intratubular pattern. Two sites (luminal and basal compartments) suggestive of the onset of neoplastic transformations in germ cells were observed in intratubular seminomas. They corroborate the hypothesis that canine seminomas possibly have pathogenesis similar to that observed in human spermatocytic seminomas. The SCTs and LCTs presented high cell morphology variation. SCTs had neoplastic cells organized in five different histological arrangements. As for LCT, solid-diffuse and cystic-vascular histological patterns were the most commonly observed. Through this study, it was possible to establish some of the leading clinical, macroscopic, and histopathological aspects of testicular neoplasms diagnosed over 19 years in the area covered by the LPV-UFSM.(AU)

Este estudo teve por objetivo caracterizar a prevalência, aspectos clínicos, macroscópicos e histopatológicos dos cães acometidos por neoplasmas testiculares, a partir dos espécimes de biópsias do Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria (LPV-UFSM) em 19 anos. Parâmetros quanto à idade, porte, raça dos cães acometidos também foram estabelecidos. De todos os cães com algum tipo de neoplasma submetido à análise histopatológica no LPV nesses 19 anos (n=1.900), 213 (11,2%) tinham ao menos um neoplasma testicular. Os tecidos de 190 cães (com 220 neoplasmas) estavam disponíveis para reavaliação histológica. Os cães deste estudo apresentaram diferentes tipos de neoplasmas testiculares com frequências relativamente semelhantes. Em ordem decrescente, os neoplasmas testiculares mais frequentes foram: seminomas (88/220), leydigomas (64/220), sertoliomas (61/220) e o tumor misto de células germinativas e do estroma do cordão sexual (MGSCT; 07/220). Dentre os cães com raça definida (119 casos), as raças de grande porte tiveram o maior número de casos (50/119), seguido das raças de pequeno (47/119) e médio porte (22/119). As idades dos cães acometidos por neoplasmas testiculares variaram de 10 meses a 18 anos. Aumento de volume testicular foi a manifestação clínica mais comum. Onze cães tinham informações sobre sinais clínicos sugestivos da síndrome da feminilização. Nos seminomas, houve o predomínio do padrão difuso sobre o intratubular. Dois locais (compartimentos luminal e basal) sugestivos de início das transformações neoplásicas nas células germinativas foram observados nos seminomas intratubulares, corroborando com a hipótese de que os seminomas caninos possivelmente tem patogênese semelhante à observada nos seminomas espermatocíticos humanos. Sertoliomas e leydigomas foram neoplasmas com alta variação na morfologia celular. Os sertoliomas tinham células neoplásicas dispostas em cinco arranjos histológicos distintos. Quanto aos leydigomas, os padrões histológicos sólido-difuso e cístico-vascular foram os mais comumente observados. Através deste estudo foi possível estabelecer alguns dos principais aspectos clínicos, macroscópicos e histopatológicos dos neoplasmas testiculares diagnosticados em 19 anos na área de abrangência do LPV-UFSM.(AU)

First case report of nematode parasitic myelopathy in a wild feline in Brazil.

Parasitic myelopathy caused by Gurltia paralysans in domestic cats is a disease commonly reported in several South American countries. The adult parasite is lodged in the meningeal veins and spinal cord, often causing clinical manifestations of vascular proliferation, thrombophlebitis, and medullary compression. Wild felines are believed to be the definitive hosts of this parasite. The infection occurs through the ingestion of paratenic hosts, but the life cycle of G. paralysans is not yet clearly understood. In this paper, we discuss a case of parasitic myelopathy in a margay (Leopardus wiedii) that died during post-surgical care. Necropsy revealed focal hemorrhages in the thoracolumbar spinal cord. A microscopic examination revealed adult nematodes and eggs inside the veins of subarachnoid space in spinal cord, suggesting G. paralysans infection. This is first description of parasitic myelopathy in a margay in Brazil.

First case report of nematode parasitic myelopathy in a wild feline in Brazil / Primeiro relato de caso de mielopatia parasitária causada por nematódeo em um felídeo selvagem no Brasil

Abstract Parasitic myelopathy caused by Gurltia paralysans in domestic cats is a disease commonly reported in several South American countries. The adult parasite is lodged in the meningeal veins and spinal cord, often causing clinical manifestations of vascular proliferation, thrombophlebitis, and medullary compression. Wild felines are believed to be the definitive hosts of this parasite. The infection occurs through the ingestion of paratenic hosts, but the life cycle of G. paralysans is not yet clearly understood. In this paper, we discuss a case of parasitic myelopathy in a margay (Leopardus wiedii) that died during post-surgical care. Necropsy revealed focal hemorrhages in the thoracolumbar spinal cord. A microscopic examination revealed adult nematodes and eggs inside the veins of subarachnoid space in spinal cord, suggesting G. paralysans infection. This is first description of parasitic myelopathy in a margay in Brazil.

Resumo Mielopatia parasitária causada por Gurltia paralysans em gatos domésticos é uma doença comumente relatada em vários países da América do Sul. O parasita adulto aloja-se nas veias das meninges e da medula espinhal, muitas vezes causando proliferação vascular, tromboflebite e compressão medular, que se manifestam como sinais clínicos. Acredita-se que os felídeos selvagens sejam hospedeiros definitivos deste parasita e que a infecção ocorre por ingestão de hospedeiros paratênicos, entretanto seu ciclo de vida completo é desconhecido. Aqui, apresentamos um caso de um gato-maracajá (Leopardus wiedii) que morreu durante a assistência pós-cirúrgica. Na necropsia, foram observadas hemorragias focais na medula espinhal toracolombar. A microscopia revelou presença de nematódeos adultos e ovos, localizados dentro das veias do espaço subaracnoide da medula espinhal, o que sugeriu a infecção por G. paralysans. Esta é a primeira descrição de mielopatia parasitária em um gato-maracajá no Brasil.

Adenosquamous carcinoma of the cervical oesophagus in a dog / Carcinoma adenoescamoso do esôfago cervical em um cão

ABSTRACT: A 9-year-old male Shih Tzu dog presented with a mass on the ventral region of the neck and developed ptyalism. Radiographs revealed a radiodense nodule located in the mid-third of the oesophagus compressing the trachea. Preoperative cytology showed large neoplastic cells with abundant vacuolated cytoplasm arranged in clusters. The nodule was removed by oesophagectomy and submitted for histopathology. Microscopically, the oesophageal mass was multilobulated and unencapsulated. It had a mixed cellular growth pattern with areas showing squamous and glandular differentiation. The squamous component of the tumor was formed by solid strands of neoplastic epithelial cells; many neoplastic cells had undergone central keratinization and sometimes formed keratin pearls. The deeper adenocarcinomatous portion of the tumor consisted of tubules filled with slightly basophilic mucinous material. Histological and immunohistochemical examination confirmed the diagnosis of primary adenosquamous carcinoma (ASC) of the esophagus. This is the first report of primary ASC of the cervical oesophagus in a dog.

RESUMO: Um cão Shih Tzu de nove anos de idade apresentou uma massa na região ventral do pescoço e desenvolveu ptialismo. As radiografias revelaram um nódulo radiodenso localizado no terço médio do esôfago que comprimia a traqueia. A citologia pré-operatória mostrou células neoplásicas grandes com citoplasma vacuolizado abundante, dispostas em aglomerados. O nódulo foi removido por esofagectomia e submetido à histopatologia. Microscopicamente, a massa esofágica era multilobulada e não encapsulada. Apresentava um padrão de crescimento celular misto, com áreas mostrando diferenciação escamosa e áreas de diferenciação glandular. O componente escamoso do tumor era formado por filamentos sólidos de células epiteliais neoplásicas; muitas células neoplásicas demonstravam queratinização central e, por vezes, formavam pérolas de queratina. A porção adenocarcinomatosa mais profunda do tumor consistia em túbulos preenchidos com material mucinoso levemente basofílico. O exame histológico e imunohistoquímico confirmaram o diagnóstico de carcinoma adenoescamoso primário do esôfago. No conhecimento dos autores, este é o primeiro relato de carcinoma adenoescamoso primário do esôfago cervical em um cão.

Use of different fixation times and application of two immunohistochemical methods for detection of KIT and Ki67 proteins in canine cutaneous mast cell tumors / Utilização de diferentes tempos de fixação e métodos imuno-histoquímicos na detecção das proteínas KIT e Ki67 em mastocitomas cutâneos caninos

Due to the high prevalence of mast cell tumors (MCTs) in the diagnostic routine, several factors, especially prognostic, have been sought to determine the biological behavior of these neoplasms. Immunohistochemistry (IHC) is one of the main tools utilized to biologically differentiate more aggressive tumors from less aggressive ones. However, some immunostainings are influenced by formalin fixation, interfering with the results. This is both a retrospective and prospective study of MCTs diagnosed in laboratory routine. A total of 25 samples, without knowledge about fixation time, were analyzed in the retrospective study, whereas 12 samples, with known fixation times, were assessed in the prospective study. Two histologic grading systems (Patnaik and Kiupel), special staining of toluidine blue, and IHC for KIT and Ki67 proteins were applied in both studies. Additionally, two amplification systems (biotinylated and non-biotinylated) for Ki67 protein and counting of the argyrophilic nucleolar organizing regions (AgNOR method) were tested in the prospective study. In the retrospective study, greater agreement between the evaluating pathologists was observed when the Kiupel system was used. IHC staining for KIT protein was effective in both studies, regardless of fixation time. IHC staining for Ki67 protein was highly sensitive to formaldehyde, and staining failure was observed in 56% of the cases in the retrospective study. In the prospective study, samples fixed for longer than 24 hours showed a reduction in the number of stained cells (altering the determination of the cell growth fraction) or showed absence of IHC staining in both amplification systems. The use of the AgNOR method to evaluate the rate of cell proliferation may be an alternative when the fixation time of the neoplasm is unknown or longer than 24 hours.(AU)

Devido a alta prevalência dos mastocitomas cutâneos caninos (MCCs) na rotina diagnóstica, vários fatores, especialmente fatores prognósticos, têm sido buscados para auxiliar na determinação do comportamento biológico desse neoplasma. A imuno-histoquímica é uma das principais ferramentas empregadas para diferenciar tumores biologicamente mais agressivos de tumores menos agressivos. Entretanto, algumas imunomarcações sofrem influência pela fixação em formol, interferindo nos resultados. Este estudo compreendeu avaliar através de uma etapa retrospectiva e uma etapa prospectiva casos de MCCs diagnosticados na rotina laboratorial. Um total de 25 amostras, sem conhecimento do tempo de fixação, foi analisado no estudo retrospectivo e 12 amostras, com tempos de fixação conhecidos, no estudo prospectivo. Foram aplicados nos dois estudos, dois sistemas de graduação histológica (Patnaik e Kiupel), a coloração especial de azul de toluidina e a imuno-histoquímica para as proteínas KIT e Ki67. Adicionalmente, no estudo prospectivo, foram testados dois sistemas de amplificação (biotinilado e não biotinilado) para a proteína Ki67 e a técnica de AgNOR (contagem das regiões organizadoras nucleolares argirofílicas). Na etapa retrospectiva, observou-se uma maior concordância entre os patologistas avaliadores quando o sistema Kiupel foi utilizado. A imunomarcação para KIT se manteve eficaz em ambos os estudos, independentemente do tempo de fixação. A imunomarcação para o Ki67 mostrou-se altamente sensível ao tempo de fixação em formol, sendo observada falha na imunomarcação em 56% dos casos do estudo retrospectivo. No estudo prospectivo, constatou-se que amostras fixadas por mais de 24 horas em formol apresentaram redução na quantidade de células imunomarcadas (alterando a determinação da fração de crescimento celular) ou apresentaram ausência de imunomarcação em ambos os sistemas de amplificação. A utilização do método AgNOR, para avaliar a taxa de proliferação celular, pode ser uma alternativa quando o tempo de fixação do neoplasma for desconhecido ou superior a 24 horas.(AU)