PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Tochetto C., Flores M.M., Kommers G.D., Barros C.S.L. & Fighera R.A. 2012. [Pathological aspects of leptospirosis in dogs: 53 cases (1965-2011).] Aspectos anatomopatológicos da leptospirose em cães: 53 casos (1965-2011). Pesquisa Veterinária Brasileira 32(5)430-443. Departamento de Patologia, Universidade Federal de Santa Maria, Av. Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: anemiaveterinaria@yahoo.com.br The pathological aspects of canine leptospirosis were studied in 53 dogs with a conclusive diagnosis of the disease, as confirmed by immunohistochemistry on renal tissue. Main necropsy lesions included icterus (79.2%) and hemorrhage (75.5%), mainly in the lungs (56.6%). Gross hepatic (56.6%) and renal (50.9%) changes were frequently found and were characterized mainly by discoloration (respectively 30.2% and 32.1%), accentuation of hepatic lobular pattern (26.4%) and white streaks in the cut surface of kidneys (22.6%). Extrarenal lesions secondary to uremia occurred in half of the cases (50.9%). Enlarged livers (11.3%), and kidneys (9.4%), and rough renal capsular surfaces (3.8%) were less common findings. In the histopathology of the kidneys (n=53), the encountered lesions (98.1%) were almost exclusively acute or subacute (96.2%) and were characterized by varying degrees of tubular nephrosis (86.8%) and non-suppurative interstitial nephritis (60.4%), with evident degenerative-inflammatory dissociation. In the histopathology of the liver (n=42), the encountered lesions (97.6%) consisted mainly of hepatocellular dissociation (78.6%), intracanalicular cholestasis (33.3%) and hepatocellular necrosis (31%). Reactive lesions, such as Kupffer cell hypertrophy, sinusoidal leucocytostasis and inflammatory mononuclear infiltrate within portal triads were observed in several cases (42.8%). In the histopathology of the lung (n=28), alveolar hemorrhage (85.7%) and edema (57.1%) were rather frequent lesions. Neutrophils and macrophages in the alveolar spaces (35.7%) and neutrophils within small pulmonary vessels (17.9%) were also frequent findings. The findings stemming from the current study should serve as an alert for Brazilian veterinary pathologists, since the pathological presentations of canine leptospirosis in this region (Central Region of the State of Rio Grande do Sul, Brazil) did not change in the last 50 years, and is still similar to that described worldwide up to the decade of 1980’s, but rather different from that currently recognized in the United States, Canada and part of West Europe. We recommend that the histopathological criteria for the diagnosis of canine leptospirosis should include the concomitant occurrence of acute or subacute tubulointerstitial nephritis, non specific reactive hepatitis and diffuse alveolar damage, including diffuse alveolar hemorrhage with capillaritis, in a dog which at necropsy had presented icterus, hemorrhage and extrarenal lesions of uremia without splenomegaly.

• Leptospirosis Leptospira icterohemorrhagiae leptospirose

Abstract in Portuguese:

RESUMO.- Tochetto C., Flores M.M., Kommers G.D., Barros C.S.L. & Fighera R.A. 2012. [Pathological aspects of leptospirosis in dogs: 53 cases (1965-2011).] Aspectos anatomopatológicos da leptospirose em cães: 53 casos (1965-2011). Pesquisa Veterinária Brasileira 32(5)430-443. Departamento de Patologia, Universidade Federal de Santa Maria, Av. Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: anemiaveterinaria@yahoo.com.br Os aspectos anatomopatológicos da leptospirose foram estudados em 53 cães que tiveram diagnóstico definitivo confirmado por imuno-histoquímica do tecido renal. Na necropsia, as principais lesões observadas incluíram icterícia (79,2%) e hemorragia (75,5%), principalmente no pulmão (56,6%). Alterações macroscópicas hepáticas (56,6%) e renais (50,9%) foram frequentes e caracterizavam-se principalmente por descolorações (30,2% e 32,1% respectivamente), acentuação do padrão lobular hepático (26,4%) e estriações brancas na superfície de corte dos rins (22,6%). Lesões extrarrenais de uremia ocorreram na metade dos casos (50,9%). Hepatomegalia (11,3%), nefromegalia (9,4%) e irregularidade da superfície capsular dos rins (3,8%) foram menos comuns. Na histologia dos rins (n=53), as lesões encontradas (98,1%) foram quase que exclusivamente agudas ou subagudas (96,2%) e caracterizavam-se por graus variados de nefrose tubular (86,8%) e nefrite intersticial não supurativa (60,4%), com evidente dissociação degenerativo-inflamatória. Na histologia do fígado (n=42), as lesões encontradas (97,6%) eram constituídas principalmente por dissociação dos cordões de hepatócitos (78,6%), colestase intra-canalicular (33,3%) e necrose hepática (31%). Lesões reativas, como hipertrofia das células de Kupffer, leucocitostase sinusoidal e infiltrado inflamatório mononuclear nos espaços porta, foram vistas em muitos casos (42,8%). Na histologia do pulmão (n=28), hemorragia (85,7%) e edema (57,1%) alveolares foram muito prevalentes. Neutrófilos e macrófagos nos espaços alveolares (35,7%) e neutrófilos no interior de pequenos vasos pulmonares (17,9%) também foram achados frequentes. Os resultados aqui demonstrados devem servir de alerta aos patologistas veterinários brasileiros, pois a apresentação anatomopatológica da leptospirose canina em nossa região (Região Central do Rio Grande do Sul, Brasil) não se modificou nos últimos 50 anos, mantendo-se semelhante àquela descrita internacionalmente até a década de 1980, mas muito diferente do que é atualmente reconhecido para os Estados Unidos, o Canadá e parte da Europa Ocidental. Recomendamos que os critérios histopatológicos para o diagnóstico da leptospirose canina devem incluir a presença concomitante de nefrite tubulointersticial aguda ou subaguda, hepatite reativa não específica e lesão alveolar difusa, incluindo hemorragia alveolar difusa com capilarite, em um cão que durante a necropsia demonstre icterícia, hemorragias e lesões extrarrenais de uremia na ausência de esplenomegalia.

Abstract in English:

ABSTRACT.- Pierezan F., Rissi D.R., Oliveira Filho J.C., Lucena R.B., Tochetto C., Flores M.M., Rosa F.B & Barros C.S.L. 2009. [Granulomatous enteritis associated with larval cyathostomiasis in horses in Rio Grande do Sul, Brazil.] Enterite granulomatosa associada a larvas de ciatostomíneos em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(5):382-386. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Five cases of granulomatous enteritis associated with cyathostomes are described in horses from three farms in Rio Grande do Sul, Brazil. The cases occurred from January 1999 to December 2007. The clinical course in two cases in which clinical follow-up was available was 10-14 days. Clinical signs presented by two horses were similar and included diarrhea (3/3), weight loss (2/3), pyrexia (1/3), tachycardia (1/3), and tachypnea (1/3). Gross changes consisted of thickening of the wall of large colon and cecum by edema and the occurrence of numerous 1-4mm, dark-tan, slightly raised multifocal pinpoints disseminated throughout the mucosa. Up on the incision of these pinpoints, brown-reddish, small (1-2mm) nematode larvae emerged. Large numbers of parasites with morphology compatible with small strongyles were observed in the lumina of large colon and cecum or adhered to the mucosae of these organs. Histologically, multiple granulomas were seen in the mucosa and submucosa of large colon and cecum. These granulomas consisted of moderate to severe inflammatory infiltrate of macrophages, epithelioid macrophages, and eosinophils surrounded by fewer lymphocytes and plasma cells. In the center of these granulomas, transversal cut sections of parasites with morphology compatible with cyathostomes larvae were observed. Additionally, there was edema and moderate to marked lymphohistioplasmacytic and eosinophilic inflammatory infiltrate throughout the mucosa and submucosa of the large colon and cecum; necrosis and lymphohistiocytic proliferation in the submucosal lymphoid follicles, with hyperplasia of goblet cells in the epithelial lining of these organs were also observed. The diagnosis of granulomatous enteritis associated with larval cyathostomiasis was made based on epidemiological, clinical, and gross findings which were confirmed by histopathology.

• Diseases of horses strongylus cyathostomes Doenças de eqüinos estrôngilos ciastotomíneos

Abstract in Portuguese:

ABSTRACT.- Pierezan F., Rissi D.R., Oliveira Filho J.C., Lucena R.B., Tochetto C., Flores M.M., Rosa F.B & Barros C.S.L. 2009. [Granulomatous enteritis associated with larval cyathostomiasis in horses in Rio Grande do Sul, Brazil.] Enterite granulomatosa associada a larvas de ciatostomíneos em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(5):382-386. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Five cases of granulomatous enteritis associated with cyathostomes are described in horses from three farms in Rio Grande do Sul, Brazil. The cases occurred from January 1999 to December 2007. The clinical course in two cases in which clinical follow-up was available was 10-14 days. Clinical signs presented by two horses were similar and included diarrhea (3/3), weight loss (2/3), pyrexia (1/3), tachycardia (1/3), and tachypnea (1/3). Gross changes consisted of thickening of the wall of large colon and cecum by edema and the occurrence of numerous 1-4mm, dark-tan, slightly raised multifocal pinpoints disseminated throughout the mucosa. Up on the incision of these pinpoints, brown-reddish, small (1-2mm) nematode larvae emerged. Large numbers of parasites with morphology compatible with small strongyles were observed in the lumina of large colon and cecum or adhered to the mucosae of these organs. Histologically, multiple granulomas were seen in the mucosa and submucosa of large colon and cecum. These granulomas consisted of moderate to severe inflammatory infiltrate of macrophages, epithelioid macrophages, and eosinophils surrounded by fewer lymphocytes and plasma cells. In the center of these granulomas, transversal cut sections of parasites with morphology compatible with cyathostomes larvae were observed. Additionally, there was edema and moderate to marked lymphohistioplasmacytic and eosinophilic inflammatory infiltrate throughout the mucosa and submucosa of the large colon and cecum; necrosis and lymphohistiocytic proliferation in the submucosal lymphoid follicles, with hyperplasia of goblet cells in the epithelial lining of these organs were also observed. The diagnosis of granulomatous enteritis associated with larval cyathostomiasis was made based on epidemiological, clinical, and gross findings which were confirmed by histopathology.