Resultado da pesquisa (78)

Termo utilizado na pesquisa Pavarini S.P.

#1 - Clinical, pathological and immunohistochemical characterization of spontaneous neoplasms in pet rodents in Northeastern Brazil

Abstract in English:

In the last decade, there has been a significant increase in the demand for small rodents such as hamsters, guinea pigs, rats, and mice to be kept as pets. Consequently, the veterinary care provided to these animals has also increased. The aim of this study was to describe gross, histopathological and immunohistochemical findings of 26 spontaneous neoplasms diagnosed in 25 pet rodents in Northeastern Brazil. A retrospective study was carried out from 2014 to 2022 in two veterinary diagnostic laboratories to identify cases of tumoriform lesions in these species. Hamsters represented the most frequent species in this study (60%, 15/25), followed by rats (28%, 7/25), guinea pigs (8%, 2/25), and mice (4%, 1/25), with a mean age of 17.63 months. The anatomical regions of the face/head and thoracic region were the most affected. The most affected tissues were the skin/subcutaneous/mucosal (65%, 15/26) and mammary gland (23%, 6/26). Eighteen different types of neoplasms were diagnosed, and T-cell lymphomas and mammary adenocarcinomas were the most diagnosed tumors, each corresponding to 12% (3/26) of the cases. Leiomyosarcoma, myxosarcoma and mammary adenocarcinoma metastases were also noted. Immunohistochemistry was essential for the diagnosis of certain malignant mesenchymal and round-cell neoplasms. Pet rodent neoplasms in Northeastern Brazil are common, especially in hamsters, and immunohistochemistry can be a useful tool for the definitive diagnosis of these tumors.

Abstract in Portuguese:

In the last decade, there has been a significant increase in the demand for small rodents such as hamsters, guinea pigs, rats, and mice to be kept as pets. Consequently, the veterinary care provided to these animals has also increased. The aim of this study was to describe gross, histopathological and immunohistochemical findings of 26 spontaneous neoplasms diagnosed in 25 pet rodents in Northeastern Brazil. A retrospective study was carried out from 2014 to 2022 in two veterinary diagnostic laboratories to identify cases of tumoriform lesions in these species. Hamsters represented the most frequent species in this study (60%, 15/25), followed by rats (28%, 7/25), guinea pigs (8%, 2/25), and mice (4%, 1/25), with a mean age of 17.63 months. The anatomical regions of the face/head and thoracic region were the most affected. The most affected tissues were the skin/subcutaneous/mucosal (65%, 15/26) and mammary gland (23%, 6/26). Eighteen different types of neoplasms were diagnosed, and T-cell lymphomas and mammary adenocarcinomas were the most diagnosed tumors, each corresponding to 12% (3/26) of the cases. Leiomyosarcoma, myxosarcoma and mammary adenocarcinoma metastases were also noted. Immunohistochemistry was essential for the diagnosis of certain malignant mesenchymal and round-cell neoplasms. Pet rodent neoplasms in Northeastern Brazil are common, especially in hamsters, and immunohistochemistry can be a useful tool for the definitive diagnosis of these tumors.


#2 - Pathological aspects of a septicemic salmonellosis outbreak caused by Salmonella serotype Typhimurium in captive blue-fronted Amazon parrots (Amazona aestiva)

Abstract in English:

There are reports of septicemic salmonellosis in exotic birds caused by Salmonella enterica serotype Typhimurium, although they are scarce and do not address the anatomopathological and immunohistochemical aspects of this condition in blue-fronted Amazon parrots (Amazona aestiva). This study aims to report an outbreak of salmonellosis by S. Typhimurium in 15 blue-fronted parrots introduced to a rehabilitation center in the state of Mato Grosso do Sul, Brazil. Hepatomegaly and splenomegaly, accompanied by flat white areas in the capsule and parenchyma, were the most frequent gross changes, histologically represented by necrotic and heterophilic hepatitis and splenitis and associated with bacteria in the cytoplasm of macrophages and free in the affected tissue. S. Typhimurium was identified from bacterial culture, PCR, and DNA sequencing. Along with immunohistochemistry samples of liver, spleen, kidney, small intestine, pancreas, thyroid, heart, and lung, immunostaining was used for Salmonella spp. without previous bacterial isolation. The lethality of this outbreak demonstrates the relevance of salmonellosis in blue-fronted parrots, which are known to be carriers of this bacteria.

Abstract in Portuguese:

Apesar de existirem relatos sobre salmonelose septicêmica em aves silvestres por Salmonella enterica sorovar Typhimurium, eles são escassos e não abordam os aspectos anatomopatológicos e imuno-histoquímicos da condição em papagaios-verdadeiros (Amazona aestiva). Este trabalho visou relatar um surto de salmonelose por S. Typhimurium em 15 papagaios-verdadeiros introduzidos em um centro de reabilitação localizado no estado de Mato Grosso do Sul, Brasil. Hepatomegalia e esplenomegalia acompanhadas por áreas planas brancacentas na cápsula e no parênquima foram as alterações macroscópicas mais frequentes, representadas histologicamente por hepatite e esplenite necróticas e heterofílicas associadas a bactérias no citoplasma de macrófagos e livres no tecido afetado. S. Typhimurium foi identificada a partir de cultura bacteriana, PCR e sequenciamento de DNA. Na imuno-histoquímica, as amostras de fígado, baço, rim, intestino delgado, pâncreas, tireoide, coração e pulmão evidenciaram imunomarcação para Salmonella spp., mesmo quando não houve isolamento bacteriano prévio. A alta letalidade deste surto demonstra relevância da salmonelose em papagaios-verdadeiros, que são majoritariamente atribuídos como hospedeiros carreadores desta bactéria.


#3 - Pituitary pars intermedia dysfunction in horses associated to pituitary adenoma

Abstract in English:

The clinical syndrome of the pituitary pars intermedia dysfunction (PPID) is the most common endocrinopathy of older horses. This syndrome is characterized by several clinical and pathological changes, which are usually associated with adenomas of the pars intermedia (PI) of the pituitary gland. The aim of this work is to describe five cases of pituitary adenoma of the PI associated with PPID in horses, addressing its clinical and pathological aspects. The horses had a mean of 22 years of age. The main clinical signs were hirsutism and paresis of hind limbs, and at post mortem examination all horses had hirsutism, and a nodule in the pituitary gland, which was histologically characterized as an adenoma of PI (5/5). Furthermore, two horses had gross lesions suggestive of chronic laminitis. Moreover, there was intense parasitism of Sarcocystis neurona (2/5), Strongylus vulgaris (1/5), Parascaris equorum (1/5), Draschia megastoma (1/5), and Klossiella equi (1/5).

Abstract in Portuguese:

A síndrome clínica da disfunção da pars intermedia da hipófise (PPID) é a endocrinopatia mais comum em cavalos idosos. Essa síndrome é caracterizada por várias alterações clínicas e patológicas, geralmente associadas a adenomas da pars intermedia (PI) da hipófise. O objetivo deste trabalho é descrever cinco casos de adenoma hipofisário de PI associado a PPID em equinos, abordando seus aspectos clínicos e patológicos. Os cavalos apresentaram média de 22 anos de idade. Os principais sinais clínicos incluíam hirsutismo e paresia dos membros pélvicos, e no exame post mortem todos os equinos apresentavam hirsutismo e um nódulo na glândula pituitária, que foi histologicamente caracterizada como um adenoma de PI (5/5). Além disso, dois cavalos tinham lesões macroscópicas sugestivas de laminite crônica. Ainda, havia intenso parasitismo de Sarcocystis neurona (2/5), Strongylus vulgaris (1/5), Parascaris equorum (1/5), Draschia megastoma (1/5) e Klossiella equi (1/5).


#4 - Increased frequency of pneumonia in dogs with meningioma in ventral rhombencephalon

Abstract in English:

Intracranial tumors occurring in specific brain regions, such as the cerebellopontine angle, may be associated with cranial nerve dysfunction and dysphagia in humans and animals. Although dysphagia is a known risk factor for pneumonia, only postoperative pneumonia has been investigated in veterinary medicine. This study aimed to describe the clinical and pathological features of dogs with untreated intracranial meningiomas and concomitant pneumonia. Data from post-mortem examination registries from 2011 to 2021 were used (n=23). The frequency of pneumonia and other characteristics were compared between dogs with meningiomas in the ventral rhombencephalon region (VR group; n=13) and those with meningiomas in other intracranial sites (OIS group; n=10). The frequency of pneumonia was higher in the VR group than in the OIS group (n=5 vs. n=0; P=0.039). Plaque-like lesions were also more common in the VR group than in the OIS group (P=0.012). Dogs with concomitant pneumonia had cerebellopontine angle (n=3) and basilar meningiomas (n=2), mainly plaque-like lesions extending to or from other brain areas. In dogs with concomitant pneumonia, meningiomas had invasive (n=5) and compressive (n=3) growth behaviors and nerve roots involved in the swallowing process were frequently affected. Microscopically, these meningiomas were classified as atypical (n=4) and meningiomas (n=1). The reported clinical signs included anorexia (n=3), adipsia (n=1), and dysphagia (n=1). Our findings suggest untreated dogs with ventral rhombencephalon meningiomas may develop cranial nerve damage and aspiration pneumonia.

Abstract in Portuguese:

Tumores intracranianos que ocorrem em regiões específicas do cérebro, como o ângulo ponto-cerebelar, podem estar associados à disfunção de nervos cranianos e disfagia em humanos e animais. Embora a disfagia seja um conhecido fator de risco para pneumonia, apenas a pneumonia pós-operatória tem sido investigada na medicina veterinária. Este estudo teve como objetivo descrever as características clínicas e patológicas de cães com meningiomas intracranianos não tratados e pneumonia concomitante. Foram utilizados dados de registros de necropsias de 2011 a 2021. A frequência de pneumonia e outras características foram comparadas entre cães com meningiomas na região do rombencéfalo ventral (grupo VR; n=13) e aqueles com meningiomas em outros sítios intracranianos (grupo OIS; n=10). A frequência de pneumonia foi maior no grupo VR do que no grupo OIS (n=5 vs. n=0; P=0,039). Lesões tipo placa também foram mais comuns no grupo VR do que no grupo OIS (P=0,012). Cães com pneumonia concomitante apresentaram meningiomas no ângulo ponto-cerebelar (n=3) e região basilar (n=2), predominantemente lesões em forma de placa que se estendem de ou para outras áreas do cérebro. Em cães com pneumonia concomitante, os meningiomas apresentaram comportamentos de crescimento invasivo (n=5) e compressivo (n=3) e as raízes nervosas envolvidas no processo de deglutição foram frequentemente afetadas. Microscopicamente, esses meningiomas foram classificados como atípicos (n=4) e papilar (n=1). Os sinais clínicos relatados incluíram anorexia (n=3), adipsia (n=1) e disfagia (n=1). Nossos achados sugerem que cães com meningiomas no rombencéfalo ventral, não tratados, podem desenvolver lesão em nervos cranianos e pneumonia aspirativa.


#5 - A comparative analysis of anatomopathological features and COX-2 expression of mammary neoplasms with malignant mesenchymal components in female dogs

Abstract in English:

Canine mammary neoplasms with malignant mesenchymal components, such as carcinosarcomas and sarcomas, belong to an uncommon and histologically heterogeneous group. Little is known about the biological behavior of these histogenic variants. This study aimed to compare the clinicopathological characteristics and the COX-2 immunohistochemical expression of different histologic subtypes of carcinosarcomas and sarcomas. Samples of 23 carcinosarcomas and 15 sarcomas from the mammary glands of female dogs were studied. Medical records were reviewed to obtain clinical data. Subsequently, histology microscope slides were analyzed to assess for mesenchymal subtypes, necrosis, vascular invasion, histologic grades, and lymph node metastasis. Immunohistochemistry was used to assess the COX-2 expression. The malignant mesenchymal proliferation was categorized into osteosarcomas (23/40), fibrosarcomas (5/40), liposarcomas (6/40) and chondrosarcomas (4/40). The osteosarcomatous differentiation was the most predominant type among the sarcomas and carcinosarcomas and was associated with vascular invasion (P=0.010) and lymph node metastases (P=0.014). High COX-2 expression was detected in 14.3% of the carcinosarcomas (carcinoma and/or sarcoma cells) and 27.3% of the sarcomas. The carcinosarcomas and sarcomas had similar clinical and pathological characteristics and developed as large tumors, with intratumoral necrosis and a predominance of high histologic grades, although the frequency of vascular invasion and lymph node metastasis was low. Osteosarcoma subtypes presented more aggressive characteristics than non-osteosarcoma subtypes.

Abstract in Portuguese:

Neoplasias mamárias caninas com componentes mesenquimais malignos, como carcinossarcomas e sarcomas, são um grupo de neoplasias pouco frequentes e histologicamente heterogêneas e pouco se sabe sobre o comportamento biológico das variantes histogênicas. O objetivo desse estudo é comparar as características anatomopatológicas e a expressão imunoistoquímica de COX-2 de diferentes subtipos histológicos de carcinossarcomas e sarcomas. Foram estudados 23 carcinosarcomas e 17 sarcomas da glândula mamária de cadelas. Os prontuários médicos foram revisados para obtenção de dados clínicos. Posteriormente, as lâminas histológicas foram avaliadas para acessar os subtipos mesenquimais, necrose, invasão vascular, grau histológico, metástase linfonodal. A imunoistoquímica foi realizada para avaliar a expressão de COX-2. Os tipos encontrados de proliferação mesenquimal maligna foram osteossarcoma (23/40), fibrossarcoma (7/40), lipossarcoma (6/40) e condrossarcoma (4/40). A diferenciação osteossarcomatosa foi predominante entre os sarcomas e carcinossarcomas e foi associado com invasão vascular (P=0,006) e metástase linfonodal (P=0,014). Uma expressão alta de COX-2 foi detectada em 14,3% dos carcinossarcomas (células carcinomatosas e/ou sarcomatosas) e 27,3% dos sarcomas. Os carcinossarcomas e sarcomas apresentaram características clínicas e patológicas semelhantes e se desenvolveram como tumores grandes, com necrose intratumoral e predomínio de alto grau histológico, mas com baixa frequência de invasão vascular e metástase distante. Os subtipos osteossarcomatosos apresentaram características mais agressivas quando comparados com subtipos não osteossarcomatosos.


#6 - Evaluation of troponin I and C in horses intoxicated by salinomycin

Abstract in English:

Ionophores are antibiotics frequently used in animals of production. The most common are monensin, salinomycin, narasin, and lasalocid. The equine species is highly susceptible to ionophores poisoning. The present study aimed to analyze the serum use of cardiac troponin I (cTnI) and the anti-troponin C immunohistochemistry (IHC) technique (anti-cTnC) as a diagnostic tool for cardiac injuries in horses spontaneously poisoned by salinomycin. Seven horses were affected by a disease lasting for 6-72 hours. Three horses recovered. The primary morphological lesions reported in the four necropsied horses that died spontaneously were necrosis of the myocardium and skeletal muscle. Immunohistochemistry for anti-cTnC was performed in selected sections of the cardiac muscle from the equine submitted for necropsy. A decrease in cTnC expression in the cytoplasm of cardiomyocytes was noticed in all four necropsied horses. Samples of serum from six horses tested for cardiac troponin I levels; the most expressive values were mainly in horses with more severe cardiac histological lesions. The serum detection of cTnI can be considered a good marker to determine cardiac damage in horses intoxicated with salinomycin with a clinical evolution of 48 hours or more. The anti-cTnC IHC aided in the detection of cardiac injury in horses independent of clinical evolution.

Abstract in Portuguese:

Ionóforos são antibióticos frequentemente utilizados em animais de produção. Dentre eles, os mais comuns são a monensina, salinomicina, narasina e lasalocida. A espécie equina é altamente suscetível à intoxicação por antibióticos ionóforos. O objetivo do presente estudo foi analisar o uso da troponina sérica cardíaca I (cTnI) e da técnica de imuno-histoquímica anti-troponina C (IHC) (anti-cTnC), como ferramenta diagnóstica para lesões cardíacas em equinos intoxicados espontaneamente por salinomicina. Sete equinos foram afetados, com evolução clínica de seis a 72 horas. Destes, quatro foram necropsiados e três se recuperaram. As principais lesões morfológicas observadas foram necrose do miocárdio e dos músculos esqueléticos. A imuno-histoquímica anti-cTnC foi realizada em amostras selecionadas de tecido cardíaco dos quatro equinos submetidos à necropsia. Em todos os casos foi observada diminuição da expressão de cTnC no citoplasma dos cardiomiócitos. Amostras de soro de seis equinos foram submetidas à dosagem de troponina cardíaca I. Os valores mais altos foram observados em equinos que apresentaram lesões histológicas cardíacas mais graves. A detecção sérica de cTnI pode ser considerada um bom marcador para determinar lesão cardíaca em equinos intoxicados com salinomicina com evolução clínica de 48 horas ou mais. A IHC anti-cTnC auxiliou na detecção da lesão cardíaca nos equinos independente da evolução clínica.


#7 - Equine abortion associated with placentitis caused by Pasteurella pneumotropica

Abstract in English:

Pasteurella pneumotropica is a bacterium that has so far not been described as a cause of placentitis in animals. Two cases of aborted equine fetuses were sent to the Department of Veterinary Pathology of the “Universidade Federal do Rio Grande do Sul” (SPV-UFRGS) for anatomopathological examination. Both cases presented suppurative placentitis associated with multiple basophilic bacterial cells. After bacterial isolation and biochemical analysis, P. pneumotropica was identified.

Abstract in Portuguese:

Pasteurella pneumotropica é uma bactéria que até o momento não foi descrita como causa de placentite em animais. Dois casos de fetos equinos abortados foram enviados ao Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS) para exame anatomopatológico. Em ambos os casos se observou placentite supurativa associada a múltiplas colônias bacterianas basofílicas. Após o isolamento bacteriano e análise bioquímica, indentificou-se P. pneumotropica.


#8 - Causes of abortion, stillbirth, and perinatal mortality in horses

Abstract in English:

Causes of abortion, stillbirth, and perinatal mortality in horses were investigated in the Department of Veterinary Pathology of the Federal University of Rio Grande do Sul (SPV-UFRGS) from 2000 to 2015. In this period, 107 cases were analyzed using macroscopic, microscopic, and complementary tests. Of these, 77 were aborted fetuses, 16 were stillbirths, and 14 were perinatal deaths. Conclusive diagnosis was established in 42.8% of the fetuses analyzed, with 28.6% classified as infectious origin, 9.1% as non-infectious, and 5.1% as other. Bacterial infections, especially those related to Streptococcus spp. were the most frequently observed. In stillborn foals, diagnosis was established in 62.5% of cases, and 50% of these were related to non-infectious causes, such as dystocia and birth traumas. As for perinatal mortality, a conclusive diagnosis was reached in 78.57% of cases, and infectious causes associated with bacterial infections accounted for 64.1% of these diagnoses.

Abstract in Portuguese:

Causas de aborto, natimortalidade e mortalidade perinatal em equinos foram investigadas no Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS) durante o período de 2000 a 2015. Nesse período, foram analisados 107 casos através de exames macroscópico, microscópico e exames complementares, desses 77 correspondiam a fetos abortados, 16 natimortos e 14 mortes perinatais. Diagnóstico conclusivo foi estabelecido em 42,8% dos fetos analisados e classificados como origem infecciosa em 28,6% dos casos, não infecciosa com 9,1% e outros com 5,1% dos casos. As infecções bacterianas, em especial as relacionadas a Streptococcus spp. foram as mais frequentemente observadas. Em potros natimortos, diagnostico foi estabelecido em 62,5% dos casos, e destes, 50% foram relacionados a causas não infecciosas, como distocia e traumas durante o parto. Quanto a mortalidade perinatal, em 78,57% dos casos houve um diagnostico conclusivo, e as causas infecciosas associadas a infecções bacterianas corresponderam a 64,1% desses diagnósticos.


#9 - Anatomopathological aspects and the use of immunohistochemistry in slaughter pigs with cutaneous lesions of erysipelas

Abstract in English:

Swine erysipelas is a disease of worldwide distribution, responsible for causing economic losses in swine and considered an occupational zoonotic disease. It is estimated that 30% to 50% of pigs are carriers and stress can predispose the appearance of clinical disease. The diagnosis of erysipelas in slaughter pigs becomes a challenge for pathologists, since scalding and dehairing, routine procedures in slaughterhouses, generate histological artifacts that often make the final diagnosis impossible. This study describes the anatomopathological aspects and evaluate the use of immunohistochemistry as a diagnostic tool in these cases. Forty-three cases of erysipelas in slaughter pigs were analyzed. Grossly, the cutaneous lesions were characteristic pink, red, or purple raised rhomboid, rectangular or square lesions (“diamond skin”). Histologically, in the dermis and subcutaneous tissue, there were suppurative vasculitis, hidradenitis and folliculitis, as well as degeneration and necrosis of the vessel wall, thrombosis and multifocal areas of necrosis. Suppurative vasculitis and damage to the blood vessel wall were observed in all cases, with varying degrees of severity. The immunohistochemical technique proved to be an effective complementary method of diagnosis, with positive immunostaining in 93%. In most cases, we observed mild immunostaining (57.5%), moderate in 22.5% and marked in 20%.

Abstract in Portuguese:

A erisipela suína é uma doença de distribuição mundial, responsável por causar prejuízos econômicos na suinocultura, além de ser uma doença zoonótica com caráter ocupacional. Estima-se que 30%-50% dos suínos sejam portadores e fatores estressantes podem predispor o aparecimento da doença clínica. O diagnóstico de erisipela em suínos de abate torna-se um desafio aos patologistas, uma vez que os processos de escaldagem e depila, rotineiros em abatedouros frigoríficos, geram artefatos histológicos que muitas vezes impossibilitam o diagnóstico final. Este trabalho descreve os aspectos anatomopatológicos e avalia o uso da imuno-histoquímica como uma ferramenta diagnóstica nestes casos. Foram analisados fragmentos de pele de 43 casos de erisipela em suínos de abate. Macroscopicamente, eram múltiplas lesões cutâneas romboides, retangulares ou quadradas rosa, vermelho ou roxo característicos (“pele de diamante”). Histologicamente, na derme e subcutâneo, havia vasculite, hidradenite e foliculite supurativas, bem como degeneração e necrose da parede de vasos, trombose e áreas de necrose multifocais. A vasculite supurativa e a lesão na parede de vasos sanguíneos foram observadas em todos os casos, em diferentes graus de severidade. A técnica imuno-histoquímica se mostrou um eficaz método complementar de diagnóstico, com imunomarcação positiva em 93%. Na maior parte dos casos observamos marcação discreta (57,5%), moderada em 22,5% e acentuada em 20%.


#10 - Osteoporosis in swine

Abstract in English:

Forty-six pigs presented muscle weakness, hind limb paresis and paralysis, weight loss, lateral recumbency, and death in a clinical course of 7 to 10 days. Two pigs were necropsied and exhibited bone fragility, bone callus formation, and multiple fractures in the limbs, ribs, and vertebrae. Microscopically, there was a diffuse and marked decrease in thickness and number of trabeculae. These were disconnected, with a “free-floating” appearance, while the cortex of the long bones was thinned, with an increase of the cortical porosity by enlargement of Haversian canals and endosteal erosion and decreased osteoblastic activity. Flame atomic absorption spectrometry in liver samples revealed significant zinc overload (>2300ppm) and copper deficiency (<33.1ppm). In this communication, we present the first pathologic description of an outbreak of osteoporosis in pigs, and we also provide a brief review of metabolic bone diseases in pigs.

Abstract in Portuguese:

Quarenta e seis suínos apresentaram fraqueza muscular, paresia e paralisia de membros pélvicos, perda de peso, decúbito lateral e morte, com um curso clínico de 7 a 10 dias. Dois suínos foram submetidos a necropsia e exibiram fragilidade óssea, formação de calo ósseo, e múltiplas fraturas em membros, costelas e vértebras. Microscopicamente notou-se difusamente um marcado decréscimo na espessura e número de trabéculas ósseas. Essas estavam desconexas, com uma aparência de flutuação, enquanto o córtex dos ossos longos estava afinado, com um aumento da porosidade pela dilatação dos canais de Haversian, erosão endosteal e diminuição da atividade osteoblástica. Espectrofotometria por chama foi realizada em amostras de fígado, e revelou um excesso de zinco (>2300ppm) e deficiência de cobre (<33.1ppm). Neste trabalho, apresentamos a primeira descrição patológica de um surto de osteoporose em suínos, além de fornecer uma breve revisão de doenças metabólicas em suínos.


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