RESUMO
Visceral leishmaniasis (VL) is an important zoonotic vector-borne disease and domestic dogs are considered the main domiciliary and peri-domiciliary reservoir of Leishmania (Leishmania) infantum in South America. Distinct eco-epidemiological scenarios associated to the prevalence of the disease, clusters of parasite genotypes and chemotypes of vectors population are described in Brazil, especially in the state of São Paulo (SP). In this context, the purpose of the present study is to evaluate the clinical signs, histopathological lesions, parasite load and cytokine profile by immunohistochemistry (IHC) in popliteal lymph nodes of canines naturally infected with L. infantum, from different municipalities of the state of SP. Eighty-three dogs with VL, 61 from northwest SP (NWSP) and 22 from southeast SP (SESP), were clinically classified in stage II, with no babesiosis and ehrlichiosis. Subcapsular inflammatory infiltration and histiocytosis were significantly higher in the SESP group (pâ¯=â¯0.0128; 0.0077, respectively). On the other hand, dogs from NWSP revealed 4.6-fold significantly higher parasite burden (pâ¯=â¯0.0004) and higher IHC scores of IL-1ß (pâ¯=â¯0.0275) and IL-4 (pâ¯=â¯0.0327) in the popliteal lymph node tissues, which may be associated with the susceptibility and progression of the disease in these dogs. Differences in immune response profile associated with higher parasite load in dogs can also contribute to explain the distinct eco-epidemiological patterns of VL in specific geographic regions.
Assuntos
Citocinas/imunologia , Doenças do Cão/imunologia , Leishmania infantum , Leishmaniose Visceral/veterinária , Linfonodos/parasitologia , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/patologia , Cães , Feminino , Leishmania infantum/imunologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/patologia , Linfonodos/patologia , Masculino , Carga ParasitáriaRESUMO
Two cases of Leishmania (Leishmania) amazonensis are reported in the domestic dog (Canis familiaris). These are the first records of this parasite in this species. The animals lived in the endemic visceral leishmaniasis area of Araçatuba, São Paulo State, Brazil and were initially diagnosed, on clinical grounds, as having visceral leishmaniasis. Attempted parasite isolation from inguinal lymph node aspirates was unsuccessful and the indirect immunofluorescent test for visceral leishmaniasis was negative in both cases. Parasites were seen in cytological preparations of their lymph nodes and the DNA obtained from these same tissues produced the expected fragment in a Leishmania specific rDNA based PCR assay. The products only hybridized with the L. (L.) amazonensis specific probe S8. No human cases of L. (L.) amazonensis have been reported in this region. These results suggest that L. (L.) amazonensis is being transmitted in the peridomestic habitat and that this parasite is responsible for a clinical condition that is similar to visceral leishmaniasis caused by L. (L.) i. chagasi that is present in the same area.
Assuntos
Doenças do Cão/diagnóstico , Leishmania/classificação , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Cães , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologiaRESUMO
Em inquéritos caninos, realizados em municípios paulistas com autoctonia de leishmaniose visceral americana (LVA), o desempenho do teste rápido imunocromatográfico (formato dipstick) empregando antígeno recombinante K39 (rK39) foi realizado em amostras de sangue total e soro de cães. Este teste foi comparado com a técnica de RIFI e com ELISA as quais foram realizadas em amostras de soro. As amostras foram colhidas de 1.333 cães, sendo 1199 selecionados por sorteio em municípios com transmissão de LVA. O grupo controle foi constituído de amostras de 134 cães portadores de outras patologias ou residentes em áreas indenes para LVA, para avaliar a especificidade do teste rápido antirK39. Nos cães selecionados por sorteio, a positividade do teste rápido anti-rK39 foi de 31,3% nas amostras de soro e de 17,4% no sangue total; a RIFI e o ELISA detectaram anticorpos anti-Leishmania em 25,1% e 27,2% das amostras, respectivamente. Todas amostras do grupo controle apresentaram resultados negativos no teste rápido. O teste rápido realizado em amostras de soro apresenta-se como ensaio simples, rápido, de baixo custo e, portanto, adequado para ser empregado como técnica alternativa de triagem diagnóstica em função de sua especificidade para as espécies do complexo Leishmania donovani, responsáveis pela leishmaniose visceral.
Canine visceral leishmaniasis (CVL) coexists with human visceral leishmaniasis (HVL) in Brazil. Dogs play an important role as reservoir of etiological agent, and for CVL dissemination. For diagnosing CVL, IFA and ELISA have been routinely employed. These assays have not been suitable for diagnosis studies owing to low sensitivity and/or specificity. The CVL diagnosis in different regions of São Paulo was assessed, comparing the performance of a immunochromatographic dipstick based rapid test using K39 recombinant antigen (rK39RT) on whole blood and serum samples, and with IFI and ELISA on serum samples. The 1,333 samples dogs were tested including 1,199 samples from randomly selected dogs from eight municipalities with CVL transmission. The control group was comprised by samples from 134 animals living VL-free area or from dogs with other diseases. Of 1,199 samples, 31.3% were positive by rK39RT on sera, and 17.4% on whole blood. Anti-Leishmania antibodies were detected in 25.1% and 27.2% of samples on IFA and ELISA, respectively. rK39RT revealed a low performance on whole blood, however on dog serum higher number of positive samples were detected. All samples from 47 dogs with other diseases were negative on rK39RT. The rK39RT is a simple, rapid, inexpensive, specific and sensitive, and suitable as an alternative screening testing.
Assuntos
Animais , Cães , Leishmaniose Visceral/diagnóstico , Proteínas Recombinantes/imunologia , Técnicas Imunológicas , Ensaio de Imunoadsorção EnzimáticaRESUMO
Com o objetivo de avaliar a participaçäo de flebotomíneos e de animais domésticos, domiciliados e/ou silvestres na epidemiologia da leishmaniose tegumentar americana, foram realizadas observaçöes em área periurbana do município de Eldorado, Vale do Ribeira, Säo Paulo. No interior da mata, as capturas de flebotomíneos ocorreram no período de janeiro de 1996 a dezembro de 1997, com armadilha de Shannon e armadilhas luminosas, tipo Falcäo modificada e em ecótopos artificiais para manutençäo de galinhas, marsupiais, roedores silvestres, hamsters e cäes com papéis embebidos com vaselina líquida, além de um pano branco estendido na parede dos recintos. A fauna de flebotomíneos esteve representada pr 10 espécies e um total de 1.066 exemplares capturados. A presença de iscas animais näo interferiu na diversidade das espécies de flebotomíneos. L. ayrozai foi a espécie predominante nesse ambiente revelando maior atividade nos meses mais secos do ano, entre abril e julho. A presença marcante dessa espécie em ambiente florestal, confere-lhe condiçöes potenciais para o papel de vetor de Leishmania sp em seu ciclo silvestre na regiäo
Observations were made in periurban area in Eldorado county, Ribeira Valley, São Paulo State, Brazil for the purpose of assessing the participation of phlebotomines, domestic, domiciliar and wildanimals in the epidemiology of American Cutaneous Leishmaniasis. Several artificial ecotopes were installedwithin the forest for the capture of phlebotomines between January 1996 and December 1997. Ten sandflyspecies represented by 1,066 specimens were captured during this period. Lutzomyia ayrozai waspredominant in the forest.The greatest peak occurred from April to July. Lu.ayrozai could be an importantvector in enzootic cicle of Leishmania in this region