Intestinal T-cell lymphoma in a coati (Nasua nasua) - Short communication.

A 10-year-old female coati (Nasua nasua) was necropsied after an 8-day history of apathy, weight loss and dehydration. Gross changes consisted of multifocal to coalescing nodules ranging from 0.5 to 2.0 cm in diameter in the wall of the small intestine, adjacent to the mesentery and in the mesenteric lymph nodes. Histologically, neoplastic CD3-positive lymphocytes infiltrated all layers of the intestine, as well as the mesenteric adipose tissue and mesenteric lymph nodes. Based on the pathological and immunohistochemical findings, a diagnosis of intestinal T-cell lymphoma was made.

Pulmonary Langerhans cell histiocytosis in cats and a literature review of feline histiocytic diseases.

OBJECTIVES: The aim of this study was to report the clinical, radiographic and pathological features of pulmonary Langerhans cell histiocytosis in four cats, and carry out a literature review of feline histiocytic diseases. METHODS: Necropsy reports archived at the Department of Veterinary Pathology of the Federal University of Rio Grande do Sul were reviewed. The clinical information was then obtained from the clinical records at the Veterinary Hospital. Routine samples had been collected during necropsy, fixed in 10% formalin, routinely processed for histology, and stained with hematoxylin and eosin. Samples of lung were submitted for bacterial and fungal culture. Tissue sections of lung underwent immunohistochemical testing for vimentin, pancytokeratin, CD18, CD3, CD79αcy, E-cadherin and Iba1. RESULTS: This disease affected mixed breed cats aged 7-14 years. Clinical signs consisted of severe mixed inspiratory and expiratory restrictive dyspnea, lethargy and anorexia. Thoracic radiographs revealed different lesion profiles, predominantly of an interstitial and alveolar pattern. Grossly, the lungs were diffusely firm and did not collapse. The pleural surface was bright and irregular due to multifocal-to-coalescent, well-demarcated, white, firm nodules that also extended into and obliterated the pulmonary parenchyma. Histological changes were characterized by poorly demarcated infiltration with histiocytic cells arranged in cohesive groups within the alveolar, bronchiolar and bronchial spaces. Histiocytic cells had intense cytoplasmic immunolabeling for vimentin and Iba1, and robust membrane immunolabeling with CD18 and E-cadherin; these cells were negative for CD3, CD79αcy and pancytokeratin in all cases. CONCLUSIONS AND RELEVANCE: This article confirms that pulmonary Langerhans cell histiocytosis is a rare disease that occurs in middle-aged to older cats and causes widespread involvement of the pulmonary parenchyma, inducing acute or chronic, progressive respiratory disease characterized by mixed restrictive dyspnea that eventually leads to death. While a definitive clinical diagnosis is challenging, the nodular appearance of the pulmonary changes, together with the histological and immunohistochemistry findings, suffice for diagnostic confirmation of pulmonary Langerhans cell histiocytosis.

Infiltrative gastric adenocarcinoma in a chinchilla (Chinchilla lanigera).

A case of infiltrative gastric adenocarcinoma in a 5-year-old female chinchilla (Chinchilla lanigera) is described. The animal died after a 5-day period of lethargy and anorexia. Gross examination revealed increased gastric volume. The gastric wall was thickened and contained numerous firm, white nodules on the serosal surface. The lumen was obliterated by a firm mass and large amount of white, mucous secretion. Numerous white, irregular plaques and nodules were observed on the mesentery, visceral surface of the diaphragm, renal capsule, and uterine serosa (implantation metastases). Histopathological examination revealed an infiltrative gastric adenocarcinoma composed of neoplastic cells organized in a gland-like pattern interspersed with connective tissue. Neoplastic cells infiltrated the lamina propria, submucosa, and muscular layers, and were positive for cytokeratin. Detection of Helicobacter spp. in the gastric mucosa failed using Warthin-Starry and Steiner silver stains or immunohistochemistry, but a Helicobacter-specific nested polymerase chain reaction followed by sequencing was positive for Helicobacter pylori and showed more than 99% similarity to the 16S ribosomal RNA gene.

Melanoma maligno anaplásico em um eqüino / Anaplastic malignant melanoma in a horse

Descreve-se um caso de melanoma maligno anaplásico em uma égua Crioula, tordilha, com 10 anos de idade, com histórico clínico de apatia, perda de peso progressiva, febre, anorexia e dispnéia. Múltiplas massas pigmentadas e não-pigmentadas, bem delimitadas ou infiltrativas, foram observadas no tecido subcutâneo e em vários órgãos. Histologicamente o neoplasma era composto de populações de células fusiformes, redondas ou poliédricas e, menos freqüentemente, de células multinucleadas e "células em anel de sinete". O diagnóstico foi realizado com base nos achados clinicopatológicos e confirmado pela microscopia eletrônica de transmissão.

A case of anaplastic malignant melanoma in a 10-year-old gray mare is described. Clinical signs included depression, progressive weight loss, fever, anorexia, and dyspnea. Multiple circumscribed or infiltrative, pigmented, and non-pigmented tumors were observed in subcutaneous tissue and in several organs. Histological examination revealed a marked variation in neoplastic cell population, which was composed by spindle, round, polyhedrical, and less frequently, multinucleated or signet ring cells. The diagnostic was based up on clinical and pathological findings, and confirmed by transmission electronic microscopy.

Aceturato de diminazeno e dipropionato de imidocarb no controle de infecção por Trypanosoma evansi em Rattus norvegicus infectados experimentalmente / Diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in Rattus norvegicus experimentally infected

Este estudo teve como objetivo avaliar o efeito do aceturato de diminazeno e do dipropionato de imidocarb no controle da infecção por Trypanosoma evansi em ratos (Rattus norvegicus) infectados experimentalmente. Cinqüenta e quatro ratos machos foram inoculados via intraperitonial com 104 tripomastigotas de T. evansi/animal. Os ratos foram monitorados diariamente por meio de esfregaço sanguíneo periférico. No momento em que se observassem oito protozoários por campo microscópico de 1000x, era iniciado o tratamento com as drogas (dia zero). O estudo foi dividido em dois protocolos terapêuticos e os fármacos foram administrados via intramuscular. O primeiro protocolo foi aplicado nos grupos A, B, C e D e o segundo protocolo nos grupos E, F, G e H. O grupo controle foi identificado como grupo I, não medicados. No primeiro protocolo, os ratos receberam uma dose única dos fármacos no dia zero e sempre que se observasse T. evansi na circulação periférica. No segundo protocolo, os roedores receberam as mesmas doses, no entanto, por cinco dias consecutivos. No primeiro protocolo, os dois princípios ativos não apresentaram eficácia curativa, ocorrendo reincidência da parasitemia após alguns dias do tratamento. No segundo protocolo, o aceturato de diminazeno eliminou a forma tripomastigota da circulação e os ratos foram eutanasiados após 90 dias do início do tratamento. Os roedores tratados com dipropionato de imidocarb apresentaram recidiva da infecção após 30 dias. Na histopatologia não se observou alteração renal e hepática relacionada à doença ou aos medicamentos testados. Com base nos resultados, foi concluído que o aceturato de diminazeno, quando administrado por cinco dias consecutivos, é efetivo no tratamento da tripanossomose em ratos.

The aim of this study was to evaluate the efficacy of diminazene aceturate and imidocarb dipropionate in the control of Trypanosoma evansi infection in rats (Rattus norvegicus) experimentally infected. Fifty-four male rats were inoculated through intraperitoneal route with 104 T. evansi trypomastigotes. The rats were evaluated daily by periferic blood smears examination and treated when eight flagellated parasites were observed in 1000x microscopic field. Two therapeutics protocols were used. The first one included Groups A, B, C, D in which the rats were submitted to a single dose of the testing drugs administered by intramuscular route at the day 0 and again when T. evansi was observed in the blood smears. The rats of the second protocol (Groups E, F, G, H) were submitted to the same treatment by five consecutive days. Four rats (Group I) were used as control and were not submitted to any treatment. Tested drugs did not show any curative effect when used in the first protocol, since parasitaemia was evident few days after treatment. The use of diminazene aceturate in the second protocol resulted in elimination of the trypomastigotes from circulation. In this case the rats were euthanized at the day 90. The infection recurred 30 days after the administration of imidocarb dipropionate. Histologically, no lesions were found in the liver or kidney. Diminazene aceturate is effective in treating trypanosomosis in rats when used five days consecutively.

Cenurose em ovinos no sul do Brasil: 16 casos / Coenurosis of sheep in southern Brazil: 16 cases

Neste trabalho são descritos casos de doença neurológica causada por Coenurus cerebralis em 16 ovinos provenientes de nove propriedades rurais do Rio Grande do Sul. Os casos ocorreram entre janeiro de 1990 e dezembro de 2006. A evolução clínica variou de 30-90 dias e os ovinos afetados apresentavam depressão (9/16), isolamento do rebanho (8/16), andar cambaleante (7/16), cegueira (4/16), desvio da cabeça (3/16), incoordenação (3/16), movimentos de pedalagem (2/16), quedas (2/16), andar em círculos, deficiência proprioceptiva nos membros torácicos e pélvicos, estrabismo, midríase, opistótono, tremores e rigidez dos membros (1/16 cada). Os achados macroscópicos foram restritos ao sistema nervoso central e caracterizados por cistos de 2 a 9cm de diâmetro preenchidos por líquido translúcido e revestidos por fina membrana. Na parte interna da membrana, havia numerosas estruturas levemente alongadas e brancas de aproximadamente 1mm de diâmetro (escólices). Na maioria dos ovinos, os cistos eram localizados no telencéfalo (12/16); em três, os cistos estavam no cerebelo e em um ovino havia um cisto no cerebelo e um na medula espinhal. Em todos os casos havia acentuada compressão e deslocamento do tecido nervoso adjacente aos cistos. Histologicamente, os cistos parasitários eram formados por dupla membrana fracamente eosinofílica da qual evaginavam múltiplos escólices esféricos acelomados. Adjacente à parede da vesícula eram observadas sucessivas camadas compostas por uma zona de necrose e mineralização, circundadas por infiltrado inflamatório composto por macrófagos epitelióides e células gigantes multinucleadas, com uma cápsula externa de tecido fibrovascular e infiltrado inflamatório linfoistioplasmocitário perivascular. Adicionalmente, havia compressão e atrofia das substâncias branca e cinzenta adjacentes. O diagnóstico de cenurose foi realizado com base nos achados epidemiológicos, clínicos e macroscópicos, e confirmado pela histopatologia.

Sixteen cases of neurologic disease caused by Coenurus cerebralis occurring in sheep from nine farms in Rio Grande do Sul, Brazil, from January 1990 to December 2006, are described. Clinical courses varied from 30 to 90 days and affected sheep developed depression (9/16), isolation from the herd (8/16), staggering (7/16), blindness (4/16), head tilt (3/16), incoordination (3/16), paddling (2/16), falls (2/16), circling, proprioceptive deficits in fore and hindlimbs, strabismus, mydriasis, opisthotonus, trembling and rigidity of the limbs (1/16 each one). Macroscopic findings were restricted to central nervous system and consisted of 2 to 9cm fluid filled cysts with numerous slightly elongated 1 mm white scolices attached to the inner wall surface of the capsule. Cysts were located in the telencephalon (12/16); in the cerebellum (3 sheep); and in the cerebellum and spinal cord (1 sheep). All cases showed severe compression and displacement of the adjacent nervous tissue. Histologically, the cyst walls were characterized by a thin walled eosinophilic vesicle in which evaginated multiple spherical acelomated scolices. The cyst wall was surrounded by successive layers consisting of an internal necrotic and mineralized band, a layer of epithelioid macrophages with abundant number of multinucleated giant cell and an external fibrovascular capsule with perivascular lymphohistioplasmacytic infiltrate. Adjacent white and gray matter were compressed and atrophied. The diagnosis was based on epidemiologic, clinical and pathologic findings and confirmed by histopathology.

Autólise da camada de células granulares do cerebelo em bovinos / Conglutination of the cerebellar granule cell layer in cattle

A autólise da camada de células granulares do cerebelo é um achado postmortem observado em bovinos e relacionado ao prolongado tempo de duração entre a morte e a fixação do encéfalo. Para observar a prevalência desse artefato, 228 cerebelos foram examinados histologicamente ao longo do verme cerebelar. Trinta e seis por cento desses casos apresentaram conglutinação cerebelar não relacionada a doença específica. Em 74,4 por cento dos casos em que foi observada conglutinação cerebelar, não foram observadas alterações histopatológicas. Histologicamente, a conglutinação cerebelar caracterizou-se por dissolução segmentar ou difusa da camada de células granulares. A descrição deste artefato é importante, pois já foi confundido como lesão relacionada a doença específica do sistema nervoso de bovinos.

Cerebellar conglutination of the granule cell layer is a postmortem artifact observed in cattle. It is related to increased time between death and fixation of the brain. In this study, 228 cerebellum were histologically analyzed throughout cerebellar vermis. Cerebellar conglutination was observed in 36 percent of the cases and it was not related to specific diseases. Seventy-four percent of the cases did not present any histological lesions in the brain. Microscopically, cerebellar conglutination was characterized by segmentar or diffuse dissolution of the granule cell layer. This artifact has been misinterpreted as resulting from specific diseases of the central nervous system in cattle, and it has to be differentiated from important antemortem lesions.

Neurological disease in cattle in southern Brazil associated with Bovine herpesvirus infection.

The occurrence of neurological disease in cattle caused by Bovine herpesvirus in 11 farms from southern Brazil between 1987 and 2007 is described. Twenty-two animals were necropsied. Major clinical signs included excessive salivation, nasal and ocular discharge, circling, recumbency, depression, incoordination, grinding of teeth, and paddling movements. Necropsy findings in 10 of 22 cattle included hyperemia and softening of the rostral portions of the telencephalic cortex, with flattening of gyri, and malacia. Cattle in 10 cases did not show any gross lesions. Histological examination in most cases revealed nonsuppurative and necrotizing meningoencephalitis with acute neuronal necrosis, edema, eosinophilic intranuclear inclusion bodies in astrocytes and neurons, and infiltration of gitter cells. No histologic lesions could be detected in 4 cases. The initial diagnosis was based upon the clinical, epidemiological, and pathological findings. The diagnosis was confirmed by virus isolation in cell culture followed by virus identification by a glycoprotein C-based polymerase chain reaction. Seven isolates were identified as Bovine herpesvirus 5, and 4 were identified as Bovine herpesvirus 1.

Intoxicação em ovinos por Nierembergia veitchii: observações em quatro surtos / Poisoning in sheep by Nierembergia veitchii: observations in four outbreaks

Foram observados casos de morte súbita e doença crônica e caquetizante em ovinos provenientes de quatro rebanhos localizados em três municípios do Rio Grande do Sul, Brasil, entre junho de 2001 e maio de 2006. De uma população total sob risco de 460 ovinos, 43 foram afetados, 29 morreram espontaneamente e 10 foram eutanasiados. Treze ovinos, provenientes dos Surtos 1 e 4, apresentaram morte súbita e grande quantidade de espuma branca na cavidade nasal e oral e 30 ovinos, provenientes dos Surtos 2 e 3, apresentaram doença crônica com perda de peso, relutância em se movimentar, andar rígido, abdômen retraído e cifose. Doze ovinos foram necropsiados. Lesões de necropsia incluíam má condição da carcaça, com depleção dos depósitos de gordura, e mineralização de vários tecidos. Havia evidente rigidez das grandes artérias, que apresentavam superfície intimal irregular e dura, com múltiplas placas irregulares brancas e opacas. Areas semelhantes de mineralização também eram observadas no endocárdio valvar ou mural, nas serosas uterina, omasal, ruminal e reticular e no parênquima renal. Em seis ovinos havia moderado a acentuado edema pulmonar e em sete ovinos havia áreas multifocais ou coalescentes, brancas e duras, na superfície subpleural dos pulmões. Histologicamente havia mineralização sistêmica dos tecidos, caracterizada por fina granulação basofílica em vários órgãos. Nas artérias, a mineralização era observada principalmente na túnica média e freqüentemente havia proliferação intimal e ocasional metaplasia condróide ou óssea da média. Em sete ovinos foi observada mineralização dos vasos da rete mirabile carotídea. No miocárdio e no pulmão, podiam ser observados focos de calcificação e metaplasia óssea em cardiomiócitos e septos alveolares, respectivamente. Em cada uma das propriedades onde ocorreram os casos havia infestação da pastagem por Nierembergia veitchii.

Sudden death and chronic disease were observed in sheep from four herds in three cities from Rio Grande do Sul, Brazil, between June 2001 and May 2006. From a total population at risk of 460 sheep of various ages 43 were affected, 29 died spontaneously and 10 were euthanatized. Thirteen sheep from outbreaks 1 and 4 had sudden death with large amount of froth in oral and nasal cavities; thirty sheep from outbreaks 2 and 3 had a chronic course of loss of weight, reluctance to move, stiff gait, tucked abdomen and kyphosis. A total of 12 sheep were necropsied. Gross changes included poor body condition with depletion of fat deposits and mineralization of several tissues. The large arteries were rigid and had a hard and irregular intimal surface due to irregular prominent whitish opaque plaques. Mineralization was also observed in valvar and mural endocardium and in the uterine, omasal, ruminal and reticular serosa and in the renal parenchyma. Moderate to severe lung edema was observed in six sheep and multifocal to coalescing hard white areas were observed in the subpleural lung parenchyma of seven sheep. Histologically there was systemic tissue mineralization characterized by fine basophilic granules deposited in several tissues. In the arteries mineralization was mainly in the subintimal media and frequently there was intimal proliferation and occasional chondroid and osseous metaplasia of the media. Mineralization of the carotid rete mirabile was observed in seven cases. Foci of mineralization and osseous metaplasia were also observed in the myocardium and alveolar septa. In each of the farms where the outbreaks occurred Nierembergia veitchii was found in the pastures.