Estudo coproparasitológico da espécie Cebus libidinosus (macaco-prego) / Fecal study of the species Cebus libidinosus (capuchin monkey)

Os estudos sobre parasitos gastrintestinais em primatas mantidos em cativeiros são importantes para o manejo da população de macacos e para a manutenção da saúde das pessoas que trabalham com esses animais, pois muitos desses parasitos são potentes causadores de zoonoses. Este trabalho objetivou estudar os parasitas presentes nas fezes da espécie Cebus libidinosus, criada em cativeiro. Foram utilizados 22 animais apreendidos pelo Ibama-PI, Ibama-PB e Cipama (Companhia Independente de Policiamento Ambiental do Piauí), no período de 2007 a 2009, que faziam parte do Projeto de Soltura Experimental em Ilhas Lacustres de Espécies do Gênero Cebus sp., do Ibama-PI. Foram encontrados parasitas do gênero Ancylostoma em 45% (10/22) das amostras e do gênero Strongyloides em 23% (05/22). No método de Willis (1921) e no método de Hoffman, o Ancylostoma sp. estava presente em 41% (09/22) e o Strongyloides sp. em 18% (04/22) das amostras. A coprocultura revelou a presença de larva do gênero Ancylostoma em 50% dos grupos estudados. A espécie Cebus libidinosus revelou-se parasitada por helmintos gastrintestinais dos gêneros Ancylostoma e Strongyloide.(AU)

The studies of gastrointestinal parasites in primates kept in captivity are important for managing the population of monkeys and to maintain the health of people who work with these animals, as many of these parasites are potent causes of zoonosis. The study investigated the parasites present in the feces of Cebus libidinosus species bred in captivity. 22 animals were seized by IBAMA-PI, IBAMA-PB and CIPAMA (Independent Company of Piaui Environmental Policing) from 2007 to 2009. Hookworm parasites of the genus were found in 45% (10/22) of samples and gender Strongiloyde in 23% (22/05) in the Willis method (1921) and Hoffman method Ancylostoma sp. I was present in 41% (09/22) and Strongyloides sp. 18% (04/22) of the samples. A stool culture revealed the presence of hookworm larvae of the genus in 50% of the groups studied. The species Cebus libidinosus proved to be parasitized by gastrointestinal helminths of Ancylostoma and Strongyloides genres.(AU)

Inflammatory response, parasite load and AgNOR expression in ear skin of symptomatic and asymptomatic Leishmania (Leishmania) chagasi infected dogs

The skin has an important role in the transmission of visceral leishmaniasis (VL) as the infection pathway in dogs. To better characterize the inflammatory response of intact skin in VL, sixty infected dogs (30 symptomatic and 30 asymptomatic) and six non-infected controls were studied. Diagnosis of visceral leishmaniasis was confirmed by RIFI and ELISA; direct visualization of the parasite in bone marrow aspirate; imprints of popliteal lymph nodes, spleen, liver and skin; culture in NNN-phase liquid Schneider's medium; and PCR (performed only in the ear skin). Amastigote forms of the parasite in intact skin were found only in symptomatic dogs. Inflammatory infiltrates were observed in all groups, varying from intense and/or moderate in symptomatic to discrete and/or negligible in asymptomatic and control animals. Parasite load was associated with the intensity of the inflammatory response and with clinical manifestations in canine visceral leishmaniasis. AgNOr as active transcription markers were expressed in inflammatory cells and within apoptotic bodies in all groups, including controls, with no statistical difference. Therefore, cell activation and transcription do occur in both symptomatic and asymptomatic canine visceral leishmaniasis and may result in more necrosis and inflammation or in apoptosis and less symptoms, depending on the parasite load.

Transmission potential, skin inflammatory response, and parasitism of symptomatic and asymptomatic dogs with visceral leishmaniasis.

BACKGROUND: Visceral leishmaniasis in Brazil is caused by the protozoan Leishmania (Leishmania) chagasi and it is transmitted by sandfly of the genus Lutzomyia. Dogs are an important domestic reservoir, and control of the transmission of visceral leishmaniasis (VL) to humans includes the elimination of infected dogs. However, though dogs are considered to be an important element in the transmission cycle of Leishmania, the identification of infected dogs representing an immediate risk for transmission has not been properly evaluated. Since it is not possible to treat infected dogs, they are sacrificed when a diagnosis of VL is established, a measure that is difficult to accomplish in highly endemic areas. In such areas, parameters that allow for easy identification of reservoirs that represents an immediate risk for transmission is of great importance for the control of VL transmission. In this study we aimed to identify clinical parameters, reinforced by pathological parameters that characterize dogs with potential to transmit the parasite to the vector. RESULTS: The major clinical manifestations of visceral leishmaniasis in dogs from an endemic area were onicogriphosis, skin lesions, conjunctivitis, lymphadenopathy, and weight loss. The transmission potential of these dogs was assessed by xenodiagnosis using Lutzomyia longipalpis. Six of nine symptomatic dogs were infective to Lutzomyia longipalpis while none of the five asymptomatic dogs were infective to the sandfly. Leishmania amastigotes were present in the skin of all clinically symptomatic dogs, but absent in asymptomatic dogs. Higher parasite loads were observed in the ear and ungueal region, and lower in abdomen. The inflammatory infiltrate was more intense in the ears and ungueal regions of both symptomatic and asymptomatic dogs. In clinically affected dogs in which few or none Leishmania amastigotes were observed, the inflammatory infiltrate was constituted mainly of lymphocytes and macrophages. When many parasites were present, the infiltrate was also comprised of lymphocytes and macrophages, as well as a larger quantity of polymorphonuclear neutrophils (PMNs). CONCLUSION: Dogs that represent an immediate risk for transmission of Leishmania in endemic areas present clinical manifestations that include onicogriphosis, skin lesions, conjunctivitis, lymphadenopathy, and weight loss. Lymphadenopathy in particular was a positive clinical hallmark since it was closely related to the positive xenodiagnosis.

QBC for the diagnosis of human and canine american visceral leishmaniasis: preliminary data.

"Quantitative Buffy Coat" (QBC) is a direct and fast fluorescent method used for the identification of blood parasites. Since Leishmania chagasi circulates in blood, we decided to test it in American visceral leishmaniasis (AVL). Bone marrow (BM) and peripheral blood (PB) of 49 persons and PB of 31 dogs were analyzed. QBC was positive in BM of 11/11 patients with AVL and in 1/6 patients with other diseases. Amastigotes were identified in PB of 18/22 patients with AVL and in none without AVL. The test was positive in 30 out of the 31 seropositive dogs and in 28/28 dogs with Leishmania identified in other tissues. QBC is a promising method for diagnosis of human AVL, and possibly for the exam of PB of patients with AVL/AIDS, for the control of the cure and for the identification of asymptomatic carriers. Because it is fast and easy to collect and execute, QBC should be evaluated for programs of reservoir control.

CD4(+) T cells participate in the nephropathy of canine visceral leishmaniasis.

Renal involvement in visceral leishmaniasis (VL) is very frequent. The renal lesions of humans and dogs are similar but their pathogenesis has not been clearly elucidated. There is growing evidence that the cellular immune response is involved in the pathogenesis of immunologically mediated glomerulonephritis. Since T cells could participate in the pathogenesis of nephropathy, in the present study we investigated the possible involvement of CD4(+) and CD8(+) T cells in the nephropathy of canine VL. Six dogs naturally infected with Leishmania (Leishmania) chagasi from the endemic area in the Northeast of Brazil, the town of Teresina in the State of Piauí, were studied. An expressive inflammatory infiltrate of CD4(+) T cells both in glomeruli and in interstitium was present in 4 animals and absent in 2. CD8(+) T cells were detected only in one animal. CD4(+) T cells alone were observed in 3 animals; when CD8+ T cells were present CD4(+) T cells were also present. CD4(+) T cells were observed in cases of focal segmental glomerulosclerosis, diffuse membranoproliferative glomerulonephritis, diffuse mesangial proliferative glomerulonephritis and crescentic glomerulonephritis. CD8(+) T cells were present only in a case of crescentic glomerulonephritis. Leishmania antigen was detected in glomeruli and in interstitial inflammatory infiltrate in 4 animals and immunoglobulins were observed in 4 dogs. In this study we observed that T cells, in addition to immunoglobulins, are present in the renal lesion of canine VL. Further studies are in progress addressing the immunopathogenic mechanisms involving the participation of immunoglobulins and T cells in canine VL nephropathy.

CD4+ T cells participate in the nephropathy of canine visceral leishmaniasis

Renal involvement in visceral leishmaniasis (VL) is very frequent. The renal lesions of humans and dogs are similar but their pathogenesis has not been clearly elucidated. There is growing evidence that the cellular immune response is involved in the pathogenesis of immunologically mediated glomerulonephritis. Since T cells could participate in the pathogenesis of nephropathy, in the present study we investigated the possible involvement of CD4+ and CD8+ T cells in the nephropathy of canine VL. Six dogs naturally infected with Leishmania (Leishmania) chagasi from the endemic area in the Northeast of Brazil, the town of Teresina in the State of Piauí, were studied. An expressive inflammatory infiltrate of CD4+ T cells both in glomeruli and in interstitium was present in 4 animals and absent in 2. CD8+ T cells were detected only in one animal. CD4+ T cells alone were observed in 3 animals; when CD8+ T cells were present CD4+ T cells were also present. CD4+ T cells were observed in cases of focal segmental glomerulosclerosis, diffuse membranoproliferative glomerulonephritis, diffuse mesangial proliferative glomerulonephritis and crescentic glomerulonephritis. CD8+ T cells were present only in a case of crescentic glomerulonephritis. Leishmania antigen was detected in glomeruli and in interstitial inflammatory infiltrate in 4 animals and immunoglobulins were observed in 4 dogs. In this study we observed that T cells, in addition to immunoglobulins, are present in the renal lesion of canine VL. Further studies are in progress addressing the immunopathogenic mechanisms involving the participation of immunoglobulins and T cells in canine VL nephropathy