Abstract in English:
ABSTRACT.- Kondo K.R.J., Fonseca C.C., Da Matta S.L.P. & Viloria M.I.V. 2009. [Histomorphometric analysis of the extracellular matrix of popliteal lymph nodes from dogs naturally infected by Leishmania (L.) chagasi.] Análise histomorfométrica da matriz extracelular do linfonodo poplíteo de cães naturalmente infectados por Leishmania (L.) chagasi. Pesquisa Veterinária Brasileira 29(8):610-616. Departamento de Veterinária, Universidade Federal de Viçosa, Av. Peter Henry Rolfs s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil. E-mail: krisregia@hotmail.com
In the Americas, canine visceral leishmaniasis is caused by Leishmania (Leishmania) chagasi, an obligatory intracellular parasite of the phagocytic-monocytic system; the main histological changes associated with this disease occur in the lymphoid organs. Although dogs are considered to be the main carriers and disseminators of leishmaniasis in urban areas, there are few studies on the histopathologic and histomorphometric aspects in dogs naturally infected by L.chagasi analyzing the interaction between parasite and extracellular matrix. The current study characterize and quantify changes in the cellular and extracellular matrix (collagens type I and III) components of the popliteal lymph node from of 22 dogs with the natural infection by L. chagasi confirmed by indirect immuno-fluorescence assay (IFA) and compare theses findings with those fund in the popliteal lymph node from 10 non-infected dogs, that reacted negative in the IFA, and were clinically healthy. Lymph node fragments were longitudinally sliced and sections were processed for routine histopathology and stained by hematoxylin and eosin. For histomorphometry, additional sections from the same lymph node were fixed in glycol methacrylate and stained with toluidine blue. Lymph nodes from affected dogs were systemically enlarged, had increased numbers of lymphoid follicles, capsule hyperplasia and hypertrophy, and significant hyperplasia of lymphoid cells. In the lymph nodes from infected dogs, quantitative analyses of collagen fibers revealed predominance of type I collagen over type III fibers. These results demonstrate that dogs infected by L.chagasi experience degradation of the extracellular matrix components and consequently destruction of the lymphoid framework, thus altering nodal morphology.
Abstract in Portuguese:
RESUMO.- Kondo K.R.J., Fonseca C.C., Da Matta S.L.P. & Viloria M.I.V. 2009. [Histomorphometric analysis of the extracellular matrix of popliteal lymph nodes from dogs naturally infected by Leishmania (L.) chagasi.] Análise histomorfométrica da matriz extracelular do linfonodo poplíteo de cães naturalmente infectados por Leishmania (L.) chagasi. Pesquisa Veterinária Brasileira 29(8):610-616. Departamento de Veterinária, Universidade Federal de Viçosa, Av. Peter Henry Rolfs s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil. E-mail: krisregia@hotmail.com
Nas Américas, a leishmaniose visceral canina é causada por Leishmania (Leishmania) chagasi, um protozoário intracelular obrigatório do sistema fagocítico mononuclear; as principais alterações histológicas associadas a essa doença ocorrem nos em órgãos linfóides. Apesar de o cão ser considerado o principal mantenedor e disseminador da leishmaniose no ambiente urbano, são escassos estudos dos aspectos histopatológicos e histomorfométricos, em cães naturalmente infectados com L. chagasi, que investiguem a interação entre o parasito e a matriz extracelular. Este estudo visou caracterizar e quantificar as alterações dos componentes celulares e da matriz extracelular (colágenos I e III) do linfonodo poplíteo de 22 cães com infecção natural por L. chagasi detectada através da reação de imunofluorescência indireta (RIF) e compará-las com as alterações encontradas no linfonodo poplíteo de 10 cães não-infectados, negativos na RIF e clinicamente saudáveis. Fragmentos dos linfonodos foram seccionados longitudinalmente, processados rotineiramente para exame histológico e corados por hematoxilina-eosina. Cortes adicionais do mesmo linfonodo incluídos em glicol metacrilato foram corados pelo azul de toluidina para histomorfometria. Linfonodos de cães infectados apresentaram linfadenopatia generalizada, aumento do tamanho e do número dos folículos linfóides, hipertrofia da cápsula e hiperplasia linfóide significativa. Nos linfonodos de cães do grupo infectado, a análise quantitativa de fibras colágenas mostrou significativo predomínio do colágeno I sobre o colágeno III. Esses resultados demonstram que cães infectados por L. chagasi apresentam degradação dos constituintes da matriz extracelular e conseqüente destruição do arcabouço linfóide, alterando a morfologia do órgão.
Abstract in English:
ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br
Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.
Abstract in Portuguese:
ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br
Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.
Abstract in English:
Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br
A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.
Abstract in Portuguese:
Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br
A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.
Abstract in English:
Recent reports on human cases with a clinical diagnosis of visceral Leishmaniasis in Corumbá, Mato Grosso do Sul state, where the agent had never been demonstrated parasitologically, caused a more thorough investigation of the local epidemiological situation of the dog population, one of the main reservoirs of the protozoa in question. Amastigotes were observed in parasitological examinations of skin and viscera in 7 out of 30 animals with clinical symptoms of kala-azar. The isolated parasites from infected dogs were identified as Leishmania donovani by biochemical methods. A serological survey was also carried out on 481 dogs from the urban area, by collecting blood on filter paper for indirect immunofluorescence and passive hemagglutination tests: The serological prevalence of the infection in the dog population studied was 8.7%, of which only 19% showed clinical signs of kala-azar. The remaining 81% was suggestive of being potential carriers without, however, ruling out the possibility of cross reactions with other animal protozoa. The canine infection. is dissiminated in practically all of the town.
Abstract in Portuguese:
Recentes relatos sobre casos humanos com diagnóstico clínico de leishmaniose visceral em Corumbá, Mato Grosso do Sul, onde o agente nunca havia sido demonstrado parasitologicamente, levou a uma melhor investigação epidemiológica local sobre a situação da população canina, um dos principais reservatórios do parasita. Formas amastigotas foram observadas através de exame parasitológico da pele e de vísceras de 7 entre 30 animais com sintomas clínicos de calazar. Os parasitas isolados de cães infectados foram identificados bioquímicamente como sendo Leishmania donovani. Inquérito sorológico foi também realizado em 481 cães da área urbana, através das reações de imunofluorescência indireta e hemaglutinação passiva, utilizando-se sangue coletado em papel de filtro. Sorologicamente, a prevalência da infecção na população canina estudada foi de 8,7%, dos quais, apenas 19% apresentavam sinais clínicos de calazar e o restante, 81 %, eram sugestivos de serem portadores em potencial, sem contudo, poder ser excluída a possibilidade de reações cruzadas com outros protozoários. A infecção canina encontra-se praticamente disseminada por toda a cidade.