Resultado da pesquisa (233)

Termo utilizado na pesquisa pequenos animais

#1 - Safety and efficacy of allogeneic bone marrow mesenchymal stem cells for treatment of canine leukopenia induced by canine parvovirus infection

Abstract in English:

This study aims to establish a therapy strategy for canine leukopenia induced by canine parvovirus (CPV) infection through intravenous infusion of allogeneic bone marrow mesenchymal stem cells (BMMSCs) and to evaluate the therapeutic effect of BMMSCs on canine parvovirus. Forty healthy 2-month-old dogs were randomly divided into four groups including the BMMSC treatment group (A), conventional treatment group (B), CPV infection group (C), and a normal control group (D). Then the A, B, and C groups were orally infected with CPV (103.25 TCID50/mL) at 1mL/kg, and the D group received the same dose of saline. After the onset of infection, Group A received mesenchymal stem cells (MSCs) and rehydration as the treatment; Group B was treated with anti-inflammatory therapeutics and rehydration; and Group C and D were injected with the same dose of physiological saline. The level of leukocytes rebounded significantly after the treatment with BMMSCs and returned to reference numbers on Day 3 after treatment, which was significantly higher than that in the conventional treatment group. The concentrations of IL-2 and IFN-α were gradually increased during the treatment, and the BMMSC treatment group exhibited significantly higher IL-2 and IFN-α concentrations than the conventional treatment group on Days 3 and 4. The expression of the virus in the blood gradually decreased during the treatment, and the BMMSC treatment group displayed a faster decrease than the conventional treatment group. These results showed the advantages of BMMSC treatment over conventional treatment. This study provides a new BMMSC treatment strategy for canine leukopenia induced by CPV infection and reveals the mechanism by which BMMSC increases leukocytes after CPV infection.

Abstract in Portuguese:

Este estudo tem como objetivo estabelecer uma estratégia terapêutica de leucopenia canina induzida pela infecção por parvovírus canino (CPV) através de infusão intravenosa de células tronco mesenquimais da medula óssea alogênica (BMMSCs) e avaliar o efeito terapêutico de BMMSCs no parvovírus canino. Quarenta cães saudáveis de dois meses de idade foram divididos aleatoriamente em quatro grupos: o grupo de tratamento de BMMSCs (A), o grupo de terapia convencional (B), o grupo de infecção por CPV (C) e um grupo controle (D). Os grupos A, B e C foram infectados oralmente com CPV (103.25 TCID50/mL) a 1mL/kg e o D recebeu a mesma dose de soro fisiológico. Após o início da infecção, o grupo A recebeu uma dose de derivadas da medula óssea (CTMMO) e hidratação como tratamento, o grupo B foi tratado com terapia anti-inflamatória e hidratação, e grupos C e D foram injetados com a mesma dose de soro fisiológico. As concentrações de IL-2 e IFN-α aumentaram gradualmente durante o tratamento, e o grupo de tratamento BMMSC mostrou concentrações significativamente maiores de IL-2 e IFN-α do que o grupo de tratamento convencional nos Dias 3 e 4. A expressão de vírus no sangue diminuiu gradualmente durante o tratamento, e o grupo de tratamento BMMSC mostrou uma diminuição mais rápida do que o grupo de tratamento convencional. Esses resultados mostraram as vantagens do tratamento BMMSC em relação ao tratamento convencional. Este estudo fornece uma nova estratégia de tratamento da BMMSC para leucopenia canina induzida pela infecção por VCP e revela o mecanismo pelo qual a BMMSC aumenta os leucócitos após infecção por VCP.


#2 - Histopathological characterization and analysis of cell proliferation in 162 cases of canine subcutaneous mast cell tumors in Brazil

Abstract in English:

here are limited publications about canine subcutaneous mast cell tumors (MCT). International studies have shown that subcutaneous MCT has longer survival times than cutaneous MCT, with lower recurrence and metastasis rates. In addition, subcutaneous MCT has a specific histopathological classification (circumscribed, combined, or infiltrative pattern). Our study evaluated 162 cases of subcutaneous MCT diagnosed from 2014 to 2017 in Brazil. The mean age of the animals was 8.6 years, with a predominance of females and higher incidence in dogs with mixed breed (n=40), followed by Boxer (n=20), Labrador Retriever (n=14), Golden Retriever (n=11) and Pug (n=10). Regarding histopathological characterization, the most common infiltrative pattern represented 54.3% of cases, followed by circumscribed (34.8%) and combined (11%) patterns. The mean mitotic index (MI) was 1.04, with 93.9% of cases presenting MI≤4 and 53.1% MI=0. The data found in this Brazilian study regarding subcutaneous MCT does not differ from those described in American studies, suggesting similar genetic and epidemiological factors. The evaluated proliferation indices suggest that subcutaneous MCT presents slow progression and should be evaluated as a distinct form of cutaneous MCT.

Abstract in Portuguese:

Há poucas informações prognósticas sobre o mastocitoma (MCT) subcutâneo em cães, apresentando maiores tempos de sobrevida e menores taxas de recidiva e metástase em comparação ao MCT cutâneo. Além disso, o MCT subcutâneo canino segue a classificação histopatológica própria, sendo subdivididos de acordo com o padrão em: circunscrito, combinado ou infiltrativo. Sendo assim, o principal objetivo desse estudo foi caracterizar a incidência e as características histopatológicas de MCT subcutâneos no Brasil. Para isso, foram avaliadas 164 amostras de MCT subcutâneos diagnosticados entre o período de 2014 a 2017 no Brasil. A média de idade dos animais foi de 8,6 anos (variação de 3 a 20 anos), com predomínio de fêmeas (64,8%) e maior incidência em cães sem raça definida (n=40), seguido de Boxer (n=20), Labrador Retriever (n=14), Golden retriever (n=11) e Pug (n=10). Em relação a caracterização histopatológica, o padrão infiltrativo foi o mais comum representando 54,3% dos casos, seguido dos padrões circunscritos (34,8%) e combinados (11%). Quanto a contagem de mitose (CM), 93,8% dos casos apresentam CM≤4 e, em 53,1%, CM=0. Os dados encontrados nesse estudo brasileiro em relação ao MCT subcutâneo reforçam outros trabalhos realizados em diferentes regiões demográficas, sugerindo fatores genéticos e epidemiológicos para a doença. Por fim, os índices de proliferação avaliados sugerem que o MCT subcutâneo apresenta progressão lenta devendo ser avaliado como uma forma distinta do MCT cutâneo.


#3 - Expression of TLR2, FOXP3, and COX2 in the synovial membrane of dogs with canine leishmaniasis-induced arthritis

Abstract in English:

Canine leishmaniasis (CanL) is a multifaceted disease triggered by the protozoan Leishmania infantum, characterized by diverse clinical presentations, including osteoarticular complications. Immune-mediated joint diseases invariably initiate at the synovial membrane, implicating its pivotal role in arthritis pathogenesis. This study aimed to investigate the influence of natural L. infantum infection on synovial fluid characteristics and the expression of immune markers, including TLR-2, FOXP3, and COX-2, in the synovial membrane. Twenty naturally infected dogs (NID) with L. infantum were sourced from the Zoonosis Surveillance Unit (ZSU). Clinical-orthopedic assessments were conducted, encompassing lameness, joint edema, crepitus, patellar luxation, and the drawer test. Synovial fluid (SF) parameters, including volume, appearance, viscosity, total nucleated cell count (TNC), neutrophil count, and total protein (TP) content, were determined. After anesthesia and euthanasia, synovial membrane specimens were obtained. SF protein concentrations categorized dogs into three groups: GI (2 to 2.5g/dL), GII (2.5 to 6.0g/dL), and GIII (>6g/dL). Inflammatory infiltrates and synovial membrane changes were assessed, and immunohistochemistry evaluated TLR-2, FOXP3, and COX-2 marker expressions. Clinical evaluations revealed various osteoarticular abnormalities in NID dogs, including lameness (55%), joint edema (25%), crepitus (30%), patellar luxation (20%), and positive drawer test (25%). Post mortem examinations revealed bilateral subchondral bone, meniscus, and trochlea erosion in 30% of cases. Amastigotes of L. infantum were identified extracellularly and within macrophages (60%). An inflammatory infiltrate was predominant in 70% of dogs, with varying intensity among the groups. Mononuclear cells, chiefly macrophages and lymphocytes, and neutrophils comprised the infiltrate. TLR-2 and COX-2 expression levels were elevated in GIII compared to GII and GI. Conversely, FOXP3 showed moderate expression in GI and minimal expression in GII and GIII. This study underscores the contributory role of L. infantum infection in the development of joint lesions in CanL. Additionally, alterations in the expression of immune markers TLR2, FOXP3, and COX2 within the synovial membrane imply the perpetuation and exacerbation of the inflammatory processes, shedding light on the intricate pathogenesis of CanL-induced arthritis.

Abstract in Portuguese:

A leishmaniose canina (LC) é uma doença causada pelo protozoário Leishmania infantum com diversas manifestações clínicas, incluindo alterações osteoarticulares. A membrana sinovial é o local inicial de eventos patogênicos em todos os tipos de doenças articulares mediadas pelo sistema imunológico. Devido a essa relação, o objetivo foi avaliar a influência da infecção natural por L. infantum nas características do líquido sinovial e na expressão de TLR-2, FOXP3 e COX-2 na membrana sinovial. Cães naturalmente infectados por L. infantum (NID, N=20) foram obtidos na Unidade de Vigilância de Zoonoses (UVZ). Critérios clínicos ortopédicos foram avaliados, assim como foram obtidas amostras de líquido sinovial por artrocentese. O volume, aspecto, viscosidade, contagem total de células nucleadas (TNC) e contagem de neutrófilos e proteína total (PT) no líquido sinovial (LS) foram determinados. Os cães foram anestesiados e posteriormente eutanasiados para obtenção da membrana sinovial. Os animais do estudo apresentaram claudicação (55%), edema (25%), crepitação na articulação do joelho (30%) e luxação patelar medial (20%) e foram positivos no teste da gaveta (25%). Trinta por cento (30%) dos cães apresentaram erosão bilateral do osso subcondral, menisco e tróclea. Amastigotas de L. infantum foram visualizadas extracelularmente e dentro de macrófagos (60% dos animais). Os cães foram ainda divididos em três grupos de acordo com a concentração de proteína no líquido sinovial: GI: 2 a 2,5g/dL (valor de referência normal), GII: 2,5 a 6,0g/dL, GIII: >6g/dL. Infiltrado celular inflamatório, bem como aumento da camada da membrana sinovial, foram identificados em 70% (14/20) dos cães. O infiltrado inflamatório estava ausente em membranas sinoviais originadas de GI, presente em GII com intensidade moderada e presente em GIII com intensidade alta. O infiltrado inflamatório era predominantemente composto por macrófagos, linfócitos e neutrófilos. Houve um aumento na expressão dos marcadores TLR2 e COX2 em GIII em comparação com os grupos GII e GI. Contudo, em relação à expressão de FOXP3, houve uma marcação moderada em GI e apenas uma marcação leve em GII e GIII. Este trabalho reforça o papel da infecção por L. infantum no desenvolvimento de lesões articulares em cães. Além disso, nosso estudo indica que a LC modifica a expressão de TLR2, FOXP3 e COX2 na membrana sinovial, o que implica a manutenção e progressão do processo inflamatório.


#4 - Detection of multiple circulating sandflies species and investigation of dogs and vectors naturally infected with Leishmania in the city of Ribeirão Vermelho, southeastern Brazil

Abstract in English:

Leishmaniasis is a zoonotic disease caused by parasites of the Leishmania genus, resulting in various clinical forms, including a highly lethal visceral form. This study aimed to identify Leishmania spp. in sandflies and dogs in a small Brazilian town. DPP® Visceral Canine Leishmaniasis (CVL) was used for screening, and ELISA and conventional PCR were used for confirmatory testing, while sandflies were captured using CDC light traps and conventional PCR targeting ITS1. The Hill series was used to identify the diversity profile of species in the sampled area using R software. The study identified a Leishmania spp. prevalence of 4.02% in dogs, exceeding the 2% limit required by the Brazilian Ministry of Health. A total of 443 sandflies belonging to 14 different species were identified, with Lutzomyia longipalpis being the most abundant (73.81%). Negligence regarding leishmaniasis in small towns can lead to late diagnosis, hence the need to implement effective strategies, including early diagnosis and treatment of human and canine cases, vector control programs, and awareness campaigns to educate the public about risks and preventive measures. These measures can help prevent the spread of leishmaniasis and improve health outcomes for affected individuals and animals.

Abstract in Portuguese:

A leishmaniose é uma doença zoonótica causada por parasitas do gênero Leishmania, resultando em várias formas clínicas, incluindo uma forma visceral altamente letal. Este estudo teve como objetivo identificar Leishmania spp. DNA em flebotomíneos e cães em uma pequena cidade brasileira. A investigação usou DPP® Visceral Canine Leishmaniasis (CVL) para triagem, e ELISA e PCR convencional para teste confirmatório, enquanto flebotomíneos foram capturados usando armadilhas de luz CDC e PCR convencional visando ITS1. A série Hill foi utilizada para identificar o perfil de diversidade das espécies na área amostrada, utilizando o software R. O estudo identificou uma prevalência de Leishmania spp. em 4,02% dos cães, ultrapassando o limite de 2% exigido pelo Ministério da Saúde do Brasil. Foi identificado um total de 443 flebotomíneos, pertencentes a 14 espécies diferentes, com Lutzomyia longipalpis sendo o mais abundante (73,81%). A negligência com a leishmaniose em cidades pequenas pode levar ao diagnóstico tardio, daí a necessidade de implementar estratégias eficazes, incluindo diagnóstico precoce e tratamento de casos humanos e caninos, programas de controle de vetores e campanhas de conscientização para educar o público sobre riscos e medidas preventivas. Essas medidas podem ajudar a prevenir a propagação da leishmaniose e melhorar os resultados de saúde para indivíduos e animais afetados.


#5 - Obesity outcomes on electrocardiographic, echocardiographic, and blood pressure parameters in cats

Abstract in English:

Obesity is considered a chronic inflammatory process that is related to metabolic impairment, respiratory distress, and cardiovascular disease. In cats, few studies have evaluated the implications of obesity on the cardiovascular system, and the existing literature is controversial. Therefore, the aim of this study is to detect pressure, electrocardiographic, and morphofunctional changes in overweight and obese cats. After clinical and laboratory evaluation, 45 animals were selected for the study. Cats were separated according to body condition score (BCS) into three groups (control, overweight, and obese). All animals underwent blood pressure measurement, electrocardiogram, and transthoracic echocardiogram. Results are presented as mean ± standard deviation (SD). Data were considered statistically significant at p<0.05. GraphPad Prism® 7.04 software was used for statistical analyses. Mean arterial pressure in obese cats was higher than in animals with ideal weight (CT 123.60 ± 8.97mmHg vs OB 143.00 ± 22.12mmHg, p<0.0138), but hypertension was not detected. On the electrocardiogram, P wave duration (CT 33.67 ± 1.56ms vs OB 37.76 ± 2.76ms; p<0.0003) and QRS complex (CT 48.14 ± 2.56ms vs OB 54.48 ± 5.51ms; p<0.002) were significantly higher in the obese group. There were no significant echocardiographic changes. There was a direct correlation between blood pressure and BCS (r:0.36, p<0.01). The P wave was positively correlated with the BCS (r:0.56, p<0.0001). Likewise, the QRS complex correlated directly with the BCS (r:0.52, p<0.0003). The results indicate cat obesity can directly affect the cardiovascular system, promoting pressure and electrocardiographic changes. Therefore, monitoring the cardiovascular system of cats with obesity is essential.

Abstract in Portuguese:

A obesidade é considerada um processo inflamatório crônico que está relacionada ao comprometimento metabólico, dificuldade respiratória e doenças cardiovasculares. Em gatos, poucos estudos avaliaram as implicações da obesidade no sistema cardiovascular e a literatura é controversa. Portanto, o objetivo deste trabalho é detectar as alterações pressóricas, eletrocardiográficas e morfofuncionais em gatos com sobrepeso e obesidade. Quarenta e cinco animais, após avaliação clínica e laboratorial, foram selecionados para o estudo. Os gatos foram separados conforme o escore de condição corporal (ECC) em três grupos (controle, sobrepeso e obesidade). Todos os animais realizaram mensuração de pressão arterial, eletrocardiograma e ecocardiograma transtorácico. Os resultados foram apresentados como média ± desvio padrão (DP). Os dados foram considerados estatisticamente significativos se p<0,05. O software GraphPad Prism® 7.04 foi usado para análises estatísticas. A pressão arterial média dos gatos obesos era maior que nos animais com peso ideal (CT 123,60 ± 8,97mmHg vs OB 143,00 ± 22,12mmHg, p<0,0138), porém não se detectou hipertensão. No eletrocardiograma, a duração da onda P (CT 33,67 ± 1,56ms vs OB 37,76 ± 2,76ms; p<0,0003) e complexo QRS (CT 48,14 ± 2,56ms vs OB 54,48 ± 5,51ms; p<0,002) foi significativamente maior no grupo obeso. Não houve alterações ecocardiográficas significativas. Houve correlação direta da pressão arterial com o ECC (r:0,36, p<0,01). A onda P correlacionou-se positivamente com o ECC (r:0,56, p<0,0001). Do mesmo modo, o complexo QRS se correlacionou diretamente com o ECC (r:0,52, p<0,0003). Os resultados indicam que a obesidade em gatos pode afetar diretamente o sistema cardiovascular, promovendo alterações pressóricas e eletrocardiográficas. Sendo assim, é indispensável o acompanhamento do sistema cardiovascular dos gatos com obesidade.


#6 - Causes of death in domestic cats during COVID-19 pandemic (2020-2021): A multi-institutional necropsy study from Mato Grosso and Rio de Janeiro, Brazil

Abstract in English:

Retrospective studies that address the diseases in the feline species are scarce. Herein, we presented the cause of death or euthanasia of cats from January 2020 to December 2021, during the first and second years of the SARS-CoV-2 pandemic. The data were obtained from necropsies performed by the Federal Rural University of Rio de Janeiro and the Federal University of Mato Grosso. A total of 96 feline necropsies were performed. In 87 cases (90.6%), we established the reason for death, while in nine cases (9.4%), the diagnoses were inconclusive. We established the diagnostic groups: infectious and parasitic (37.5%), neoplasm (14.5%), malformation (7.3%), lower urinary tract disease (7.3%), degenerative (6.2%), traumas (6.2%), other causes (8.4%) and iatrogenic (3.1%). The most common cat diseases in Mato Grosso and Rio de Janeiro were infectious. The most common inflammatory lesions were bacterial and viral pneumonia. Alphaherpesvirus (FeHV), Mycoplasma sp., and Pseudomonas sp. were the main detected agents.

Abstract in Portuguese:

Estudos retrospectivos que abordam doenças em felinos domésticos são escassos. Apresentamos aqui a causa da morte ou razões para eutanásia de gatos domésticos entre janeiro de 2020 e dezembro de 2021, durante o primeiro e segundo ano da pandemia de SARS-CoV-2. Os dados foram obtidos em necropsias realizadas pela Universidade Federal Rural do Rio de Janeiro e Universidade Federal de Mato Grosso. Foram realizadas 96 necropsias de felinos. Em 87 casos (90,6%) foi estabelecido a causa da morte e em nove casos (9,4%) os diagnósticos foram inconclusivos. Estabelecemos os grupos diagnósticos: infecciosos e parasitários (37,5%), neoplasias (14,5%), malformações (7,3%), doenças do trato urinário inferior (7,3%), degenerativas (6,2%), traumas (6,2%), outras causas (8,4%) e iatrogênicas (3,1%). As doenças mais frequentes em gatos do Mato Grosso e Rio de Janeiro foram as infecciosas. As lesões inflamatórias mais frequentes foram as pneumonias bacterianas e virais. Os principais agentes detectados foram Alphaherpesvirus (FeHV), Mycoplasma sp. e Pseudomonas sp.


#7 - Feline application/inflammation-associated sarcoma: Gross aspects and histomorphological

Abstract in English:

Feline injection-site sarcomas in felines account for more than 40% of cutaneous and subcutaneous neoplasms in felines. The present study aimed to describe the macroscopic and histomorphological findings of feline application/injection sarcomas. Samples from 31 feline tumors with a history of feline application/inflammation sarcoma were re-evaluated regarding histological subtype, mitotic index and score, depth of tissue invasion, and presence of inflammation considering the location, intensity and predominant cell types. Of the 31 samples from felines diagnosed with sarcoma at the application/inflammation site, 87.15% were cats with no defined breed (NDB), with a mean age of 8.5 years. The predominant anatomical sites were the back and flank/abdomen, both with 29% (9/31), and the prevalent histological subtype was fibrosarcoma at 77.4% (24/31), followed by anaplastic giant cell sarcoma at 12.9% (4/31) and myxosarcoma 9.6% (3/31). The histological grade with the highest number of cases was III (51.6%), followed by Grade II (35.4%) and I (12.9%). The mean of the longest axis measurements varied between the different tumor grades without being significant, with the average being 2.5±2.79cm in Grade I tumors and 3.2±2.28cm in Grade II tumors. and 4.68±2.07cm in Grade III tumors. Necrosis was observed in 74.2% of tumors. The tissue inflammation score was mild to moderate in 58% of cases and severe in 32.2%, with lymphocytic and lymphoplasmacytic infiltrates being prevalent, with 25.8% each, followed by lymphoplasmohistiocytic with 22.6%. The infiltration depth was 38.7% in muscle tissue, followed by 32.2% in the subcutaneous tissue. Pleomorphism was accentuated in 51.6%. Desmoplasia was moderate in 45.1%. Satellite nodules were present in 29% of cases, and 19.4% had macrophages with intracytoplasmic content suggestive of adjuvants. Surgical margins were infiltrated (M1) in 48.4% and narrowed in 25.8% (M2). The anatomical locations observed were different from those recommended by the Vaccine-Associated Feline Sarcoma Task Force (VAFST); in most cases, the adjuvanted macrophage was not present. From this data, we can suggest that sarcomas in felines are not only correlated to the vaccine application, corroborating the hypothesis that any material, whether liquid or solid, and any chronic inflammatory process in the subcutaneous tissue of cats can induce the entity if they are predisposed to do so. The detailed histomorphological data evaluated in this study were key points and provided important information about tumor behavior, being a tool for clinical-oncological decision-making.

Abstract in Portuguese:

Feline injection-site sarcomas in felines account for more than 40% of cutaneous and subcutaneous neoplasms in felines. The present study aimed to describe the macroscopic and histomorphological findings of feline application/injection sarcomas. Samples from 31 feline tumors with a history of feline application/inflammation sarcoma were re-evaluated regarding histological subtype, mitotic index and score, depth of tissue invasion, and presence of inflammation considering the location, intensity and predominant cell types. Of the 31 samples from felines diagnosed with sarcoma at the application/inflammation site, 87.15% were cats with no defined breed (NDB), with a mean age of 8.5 years. The predominant anatomical sites were the back and flank/abdomen, both with 29% (9/31), and the prevalent histological subtype was fibrosarcoma at 77.4% (24/31), followed by anaplastic giant cell sarcoma at 12.9% (4/31) and myxosarcoma 9.6% (3/31). The histological grade with the highest number of cases was III (51.6%), followed by Grade II (35.4%) and I (12.9%). The mean of the longest axis measurements varied between the different tumor grades without being significant, with the average being 2.5±2.79cm in Grade I tumors and 3.2±2.28cm in Grade II tumors. and 4.68±2.07cm in Grade III tumors. Necrosis was observed in 74.2% of tumors. The tissue inflammation score was mild to moderate in 58% of cases and severe in 32.2%, with lymphocytic and lymphoplasmacytic infiltrates being prevalent, with 25.8% each, followed by lymphoplasmohistiocytic with 22.6%. The infiltration depth was 38.7% in muscle tissue, followed by 32.2% in the subcutaneous tissue. Pleomorphism was accentuated in 51.6%. Desmoplasia was moderate in 45.1%. Satellite nodules were present in 29% of cases, and 19.4% had macrophages with intracytoplasmic content suggestive of adjuvants. Surgical margins were infiltrated (M1) in 48.4% and narrowed in 25.8% (M2). The anatomical locations observed were different from those recommended by the Vaccine-Associated Feline Sarcoma Task Force (VAFST); in most cases, the adjuvanted macrophage was not present. From this data, we can suggest that sarcomas in felines are not only correlated to the vaccine application, corroborating the hypothesis that any material, whether liquid or solid, and any chronic inflammatory process in the subcutaneous tissue of cats can induce the entity if they are predisposed to do so. The detailed histomorphological data evaluated in this study were key points and provided important information about tumor behavior, being a tool for clinical-oncological decision-making.


#8 - Cardiopulmonary radiographic changes in dogs naturally infected with Dirofilaria immitis

Abstract in English:

Heartworm disease is a zoonosis caused by Dirofilaria immitis, a nematode parasite of worldwide distribution and considered one of the most virulent of dogs, which are definitive and infected hosts during the blood meal of vector mosquitoes (Aedes sp., Anopheles sp. and Culex sp.). The disease has a worldwide prevalence, with a higher incidence in tropical and subtropical climate areas, and affects animals of any breed, sex, and age group. Most animals are asymptomatic, but the disease can cause various cardiovascular and respiratory symptoms. The pathophysiology is related to vessel obstruction and an intense inflammatory reaction in the lung parenchyma, with cardiovascular and respiratory symptoms leading to signs that can be severe and lead to the death of the host. It can be diagnosed through blood tests, and chest X-rays are used to assess the severity of clinical signs and help establish a prognosis. Cardiovascular alterations appear as an increase in vascular caliber, an increase in the right heart silhouette, and pulmonary patterns compatible with infection. This study aimed to describe the conditional radiographic changes caused by the parasite in the lungs, intrathoracic vessels and heart in 30 dogs, independent of breed and sex, with an average age of 9.9 years and an average weight of 10.25kg, originating from routine care at a veterinary hospital in the city of Rio de Janeiro, from January 2022 to December 2022. All animals were diagnosed with a positive heartworm infection and cardiorespiratory symptoms as essential conditions for participation in the study. The animals were x-rayed and had their lung patterns evaluated, in addition to measuring their vascular caliber and cardiac indices using vertebral-heart size (VHS), manubrium-heart size (MHS) and sphericity index (CSI). Most animals presented pulmonary patterns such as bronchoalveolar and bronchial and increased VHS and MHS indices. Increased and borderline values of CSI measurements were found in half of the patients, demonstrating that the parasite can trigger significant radiographic changes or present potential further worsening.

Abstract in Portuguese:

A dirofilariose é uma zoonose causada pela Dirofilaria immitis, parasita nematoide de distribuição mundial e considerado um dos mais patogênicos de cães, que são hospedeiros definitivos e infectados durante o repasto sanguíneo de mosquitos vetores (Aedes sp., Anopheles sp. e Culex sp.). A doença apresenta prevalência mundial, com maior incidência em áreas de clima tropical e subtropical, acometendo animais de qualquer raça, sexo e faixa etária. A maioria dos animais é assintomática, entretanto, a doença pode causar diversos sintomas cardiovasculares e respiratórios. A fisiopatologia se relaciona com a obstrução de vasos e com intensa reação inflamatória no tecido pulmonar, com sintomatologia cardiovascular e respiratória, levando a sinais que podem ser graves e levar ao óbito do hospedeiro. Pode ser diagnosticada através de exames de sangue e as radiografias de tórax são utilizadas para avaliar a gravidade dos sinais clínicos e auxiliar no estabelecimento do prognóstico. Alterações cardiovasculares surgem como aumento de calibre vascular, aumento de silhueta cardíaca direita e padrões pulmonares compatíveis com infecção. No presente artigo objetivou-se descrever as alterações radiográficas estabelecidas pelo parasita nos pulmões, nos vasos intratorácicos e no coração em 30 cães, independente de raça e sexo, com média de idade 9,9 anos e média de peso 10,25kg, oriundos da rotina de atendimento de um hospital veterinário na cidade do Rio de Janeiro, entre Janeiro de 2022 e Dezembro de 2022. Todos os animais possuem diagnóstico positivo para infecção por dirofilariose e sintomatologia cardiorrespiratória como condição indispensável para pertencerem ao estudo. Os animais foram radiografados e tiveram os padrões pulmonares avaliados, além da medição do calibre vascular e dos índices cardíacos através do VHS (índice cardio-vertebral), MHS (ou índice manúbrio-esternal) e CSI (índice de esfericidade). A maioria dos animais apresentou padrão pulmonar como broncoalveolar e bronquial e índices de VHS e MHS aumentados. Aumento e valores limítrofes das medidas de CSI foram encontrados em metade dos pacientes, demonstrando que o parasita pode desencadear alterações radiográficas significativas ou apresentar potencial agravamento posterior.


#9 - Detection of occult metastases of mammary carcinomas in lymph nodes of dogs by immunohistochemistry combined with histochemistry techniques

Abstract in English:

Lymph node status is considered an important clinical prognostic factor in canine mammary carcinomas and women’s breast neoplasms. However, occult isolated tumor cells (ITCs) can be missed during hematoxylin and eosin (HE) analyses. Immunohistochemistry (IHC) for cytokeratin can be used to detect carcinomatous occult ITCs in mammary drainage lymph nodes. However, brown pigments, such as hemosiderin and ceroid in lymph nodes, may hinder the search for occult metastases by IHC utilizing DAB (3,3′-diaminobenzidine) as the chromogen. The aim of this study was to identify ITCs in canine lymph nodes of cases in which it was not detectable by routine HE evaluation through IHC for cytokeratin (AE1/AE3) combined with histochemistry techniques, such as Perls’ Prussian blue and periodic acid-Schiff (PAS), to improve the detection of occult metastases when hemosiderin and ceroid were present in these lymph nodes. For this, 25 tubulopapillary mammary carcinomas with their respective submitted 29 regional lymph nodes, previously given as free of tumor cells by HE analyses, were selected. Mammary tumors were graduated, and vascular invasion was investigated in these tumors. The submitted lymph nodes were reevaluated in HE, looking for occult metastases. IHC for cytokeratin (AE1/AE3) was used to detect occult metastases in mammary lymph nodes. Subsequently, a combined technique of IHC with Perl’s Prussian blue (for hemosiderin) or PAS (for ceroid) was performed to optimize the detection of ITCs by IHC, distinguishing them from pigments. Occult metastases were classified by their microanatomical location in subcapsular, cortical and medullary. Hemosiderin and ceroid were searched in lymph nodes and quantified as low, moderate, or high. The amount of pigments with a percentage of ITCs was also compared. Isolated tumor cells were found in 24.1% (7/29) of mammary lymph nodes. These ITCs were located mainly in subcapsular sinuses (4/7; 57.1%), followed by cortical (2/7; 28.5%) and medullary sinuses (1/7; 14.3%). There were concomitant lymph nodes with ITCs in 33.4% (2/6) of cases with vascular invasion. Hemosiderin and ceroid were present in about 90% of the 29 lymph nodes analyzed. In 42.8% (3/7) of lymph nodes with ITCs, hemosiderin and/or ceroid were in the same location as ITCs. It was found that lymph nodes in which ITCs were detected also present high amounts of hemosiderin (3/7; 42.9%) and low amounts of ceroid (5/7; 71.4%). In this study, IHC for cytokeratin (AE1/AE3) was an efficient method to detect occult tumor cells. IHC combined with Perls’ Prussian blue or with PAS proved to be a helpful way to investigate the presence of occult metastases in the lymph nodes of mammary canine tumors. It allowed distinguishing hemosiderin and ceroid, respectively, from ITCs in the same slide of IHC (immunostained by DAB), favoring a more accurate analysis by pathologists, which can be useful for the oncological staging of these patients.

Abstract in Portuguese:

O status nodal é considerado um importante fator prognóstico clínico em cães com carcinomas mamários e em mulheres com neoplasmas mamários. No entanto, durante a análise histopatológica convencional (coloração de hematoxilina e eosina - HE), células neoplásicas podem permanecer ocultas no linfonodo. Imuno-histoquímica (IHQ) para citoqueratina pode ser utilizada para detectar células carcinomatosas isoladas ocultas em linfonodos de drenagem mamária. Entretanto, a presença de pigmentos marrons, como a hemossiderina e o ceroide em linfonodos, pode dificultar a procura por metástases ocultas durante a análise por IHQ utilizando o DAB (3,3′-diaminobenzidina) como cromógeno. O objetivo deste estudo foi identificar células tumorais isoladas (CTIs), não detectadas pela avaliação de rotina (HE), em linfonodos de cães, através de IHQ para citoqueratina (AE1/AE3) combinada com técnicas histoquímicas, como azul da Prússia e ácido periódico Schiff (PAS), para otimizar a detecção de metástases ocultas, quando os pigmentos hemossiderina e ceroide estavam presentes nos linfonodos. Para esta finalidade, 25 carcinomas mamários túbulo-papilares com seus respectivos 29 linfonodos regionais remetidos, previamente diagnosticados como livres de células neoplásicas pelo HE foram selecionados. Os tumores mamários foram graduados e a presença de invasão vascular foi investigada nestes tumores. Os linfonodos submetidos foram reavaliados histologicamente no HE, à procura de metástases ocultas. IHQ para citoqueratina (AE1/A3) foi utilizada para detectar metástases ocultas nos linfonodos mamários. Subsequentemente, técnicas combinadas de IHQ com azul da Prússia (para hemossiderina) ou PAS (para ceroide) foram realizadas para otimizar a detecção de CTIs através da IHQ, distinguindo-as dos pigmentos. As metástases ocultas foram classificadas pela sua região microanatômica nodal em subcapsular, cortical e medular. Hemossiderina e ceroide foram identificados no linfonodo e classificados de acordo com sua quantidade em baixa, moderada e alta. Também foram comparadas a quantidade de pigmentos com a porcentagem de CTIs. Foram encontradas CTIs em 24,1% (7/29) dos linfonodos mamários. Estas CTIs estavam localizadas principalmente em seios subcapsulares (4/7; 57,1%), seguido pela cortical (2/7; 28,5%) e seios medulares (1/7; 14,3%). Em 33,4% (2/6) dos casos com invasão vascular havia, concomitantemente, linfonodos de drenagem com CTIs. Hemossiderina e ceroide estavam presentes em cerca de 90% dos 29 linfonodos analisados. Em 42,8% (3/7) dos linfonodos com CTIs, hemossiderina e/ou ceroide estavam na mesma localização das CTIs. Os linfonodos que apresentaram CTIs também apresentavam grande quantidade de hemossiderina (3/7; 42,9%) e pequena quantidade de ceroide (5/7; 71,4%). Neste estudo, IHQ para citoqueratina (AE1/AE3) foi um método eficiente para detecção de células tumorais ocultas. A técnica combinada de IHQ com azul da Prússia ou com o ácido periódico de Schiff (PAS) mostrou ser uma maneira útil de investigar a presença de metástases ocultas em linfonodos de cães com tumores mamários caninos, distinguindo a hemossiderina e o ceroide, respectivamente, de CTIs na mesma lâmina de IHQ (imunomarcadas por DAB), favorecendo uma análise mais acurada pelos patologistas, o que pode ser útil no estadiamento oncológico destes pacientes.


#10 - Neurocryptococcosis in dogs and cats: Anatomopathological and fungal morphological aspects in a case series

Abstract in English:

Cryptococcosis is a fungal infection that commonly affects dogs and cats, often manifesting with neurological involvement. This study investigated the neuropathological characteristics of cryptococcosis in nine cats and two dogs submitted to necropsy through gross pathology and histopathological analysis. Clinical history, lesion location, fungal burden, type and intensity of inflammatory infiltrate, lesions in nervous parenchyma, and morphological characteristics of yeast cells were evaluated. Additionally, fungal morphological criteria, such as capsule and yeast wall thickness and budding frequency, were analyzed in each neurolocation. The Alcian blue stain method was utilized to enhance the visualization of yeasts. Debilitating and/or immunosuppressive conditions were described in five cases. Two cats were recently adopted from the streets, and one cat was treated with corticosteroids. One dog had severe cachexia and generalized weakness, and another dog had leukopenia with left shift. Only six cases (54%) had neurological signs. Gross central nervous system (CNS) lesions were found in five cases and appeared as irregular, friable, soft, gelatinous, and grayish masses with distinct borders. The telencephalic cortex and the cerebellum were the most frequently affected CNS locations observed in all cases. The first exhibited a higher fungal burden and a milder inflammatory response than other neurolocations. The cerebellum was also affected in all cases but showed a slightly higher inflammatory response and a lower fungal burden compared to the telencephalic cortices. Additionally, lung involvement was observed in all cases as well. The inflammatory intensity associated with the yeasts in the CNS was predominantly mild to moderate, being severe only in two cases, and the fungal burden was more often moderate or severe, being mild in only two cases. The observed heterogeneity in the inflammatory response and fungal burden reveals the complex nature of this infection. Other affected nervous tissues were the optic nerve, the spinal cord nerve roots and the ganglia, mostly in cats. In conclusion, our study shows the neuropathological features of cryptococcosis in a case series in cats and dogs, emphasizing the importance of considering specific neurolocations to diagnose this fungal infection and contributing to a better understanding of the simultaneous involvement of the respiratory and nervous systems.

Abstract in Portuguese:

A criptococose é uma infecção fúngica que comumente afeta cães e gatos, muitas vezes se manifestando com envolvimento neurológico. Neste estudo, foram investigadas as características neuropatológicas da criptococose em nove gatos e dois cães submetidos à necropsia, por meio da análise macroscópica e histopatológica. Foi avaliada a história clínica, localização das lesões, carga fúngica, tipo e intensidade do infiltrado inflamatório, lesões no parênquima nervoso e características morfológicas das células de levedura. Além disso, critérios morfológicos fúngicos, como espessura da cápsula e parede da levedura e frequência de brotamento, foram analisados em cada neurolocalização. Para aprimorar a visualização das leveduras, foi utilizada a técnica de coloração de azul alciano. Condições debilitantes e/ou imunossupressoras foram detectadas em cinco casos. Condições debilitantes e/ou imunossupressoras foram descritas em cinco casos. Dois gatos foram recentemente adotados das ruas e um gato foi tratado com corticosteroides. Um cão apresentava caquexia grave e fraqueza generalizada e outro cão apresentava leucopenia com desvio à esquerda. Apenas seis casos (54%) apresentaram sinais neurológicos. Lesões macroscópicas no sistema nervoso central (SNC) foram encontradas em cinco casos, aparecendo como massas irregulares, friáveis, moles, gelatinosas e acinzentadas, com bordas distintas. O córtex telencefálico e o cerebelo foram as localizações do SNC mais frequentemente afetadas, observadas em todos os casos. O córtex apresentou uma carga fúngica mais elevada e uma resposta inflamatória mais branda em comparação com outras neurolocalizações. O cerebelo também foi afetado em todos os casos, apresentando uma resposta inflamatória um pouco mais elevada e carga fúngica mais baixa do que o córtex telencefálico. Além disso, o envolvimento pulmonar também foi observado em todos os casos. A intensidade inflamatória associada às leveduras no SNC, foi predominantemente leve a moderada, sendo grave apenas em dois casos, e a carga fúngica foi mais frequentemente moderada ou grave, sendo leve em apenas dois casos. A heterogeneidade observada na resposta inflamatória e carga fúngica revela a natureza complexa dessa infecção. Outros tecidos nervosos afetados foram o nervo óptico e as raízes e gânglios nervosos da medula espinhal, principalmente em gatos. Em conclusão, nosso estudo mostra as características neuropatológicas da criptococose em uma série de casos em gatos e cães, enfatizando a importância de considerar neurolocalizações específicas para o diagnóstico dessa infecção fúngica. Além disso, contribui para uma melhor compreensão do envolvimento simultâneo dos sistemas respiratório e nervoso.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV