Influência de fatores ambientais na Leishmaniose visceral no Rio Grande do Norte

The Visceral Leishmaniose (LV) disease is endemic in some places in Brazil. It is caused by the protozoa Leishmania chagasi, being transmitted for vector, the phlebotomies, Lutzomyia longipalpis. In virtue of the expansion of the illness in Rio Grande do Norte, it is necessary to evaluate the determinative ambient factors in the proliferation of the vector for better control of the illness. The variable rainfall and the social variables had been analyzed using space regression with two models and the ambient variable of ZANE and the variables analyzed in 205 houses in the cities of Natal, Extremoz, Nísia Floresta, São Gonçalo do Amarante, São Jose do Mipibu, Parnamirim and Macaíba the Person and ML Chi-square were used . The analyses had shown that high rainfall, plain relief, the forest, the humid tropical climate the activities of production culture of sugar cane and fruit culture and the presence of bovines increase the risk of the LV. The work showed that it has space aggregation and that ambient factors influence in the LV in the State

Preferência alimentar e identificação das principais fontes de repasto sanguíneo de fêmeas Lutzomyia (Diptera: Psychodidae) em áreas endêmicas para leishmaniose visceral na grande Natal

Leishmaniasis are endemic diseases wild spread in the New and Old World, caused by the flagelated protozoan Leishmania. In the New World, the distribution of different forms of leishmaniasis is mostly in tropical regions. In the State of Rio Grande do Norte, Northeast Brazil, 85% of the captured sand flies fauna is Lutzomyia longipalpis. The distribution of the sand fly vector in the state overlaps with the disease distribution, where the presence of sand flies is associated with presence of animals shelters. The aim of this study was to analyse the blood meal preference of sand flies vector from the genus Lutzomyia spp. in laboratory conditions, to verify the vector life cicle at different temperatures sets and to identify the main blood meal source in endemic areas for visceral leishmaniasis (VL) at peri-urban regions of Natal. Sand flies samples were collected from the municipalities of São Gonçalo do Amarante and Nísia Floresta where female sand flies were grouped for the colony maintenance in the laboratory and for the analysis of the preferred source of sand fly blood meal in natural environment. The prevalence of blood meal preference and oviposition for the females sand flies was 97% for Cavia porcellus with oviposition of 19 eggs/female; 97% for Eqqus caballus with 19 eggs/female; 98% for human blood with 14 eggs/female; 71.3% for Didelphis albiventris with 8.4 eggs/female; 73% for Gallus gallus with 14 eggs/female; 86% for Canis familiaris with 10.3 eggs/female; 81.4% for Galea spixii with 26 eggs/female; 36% for Callithrix jachus with 15 eggs/female; 42.8% for Monodelphis domestica with 0% of oviposition. Female sand flies did not take a blood meal from Felis catus. Sand flies life cycle ranged from 32-40 days, with 21-50 oviposition rates approximately. This study also showed that at 32°C the life cycle had 31 days, at 28° C it had 50 days and at 22°C it increased to 79 days. Adjusting the temperature to 35°C the eggs did not hatch, thus blocking the life cycle. A total of 1540 sand flies were captured, among them, 1.310 were male and 230 were female. Whereas 86% of the sand flies captured were Lu. longipalpis as compared to 10.5% for Lu. evandroi and, 3.2% for L. lenti and 0.3% for Lu whitmani. The ratio between female and male sandfly was approximately 6 males to 1 female. In Nísia Floresta, 50.7% of the collected females took their blood meal from armadillo, 12.8% from human. Among the female sand flies captured in São Gonçalo do Amarante, 80 of them were tested for the Leishmania KDNA infectivity where 5% of them were infected with Leishmania chagasi. Female Lutzomyia spp. showed to have an opportunistic blood meal characteristic. The behavioral parameters seem to have a higher influence in the oviposition when compared to the level of total proteins detected in the host s bloodstream. A higher Lu. longipalpis life cycle viability was observed at 28°C. The increase of temperature dropped the life cycle time, which means that the life cycle is modified by temperature range, source of blood meal and humidity. Lu longipalpis was the most specie found in the inner and peridomiciliar environment. In Nísia Floresta, armadillos were the main source of blood meal for Lutzomyia spp. At São Gonçalo do Amarante, humans were the main source of blood meal due to CDC nets placed inside their houses

Perfil de memória e ativação de linfócitos T na leishmaniose visceral

Visceral leishmaniasis (VL) in Brazil is a disease caused by Leishmania infantum chagasi (L.i.chagasi). The clinical evolution post-infection depends on the vertebrate host immune response, which is genetically mediated. This study aimed to evaluate the immune response of individuals living in endemic area for VL in the state of the Rio Grande do Norte, considering individuals with VL under treatment (n = 9), recovered VL <1 year post treatment (n = 10), > 10 years posttreatment (n = 9), uninfected individuals living in endemic areas (n = 7), individuals that lost DTH response (n=6) and asymptomatic individuals for VL (n=9). Peripheral blood cells were evaluated in the presence and absence of soluble Leishmania antigens (SLA) and ex vivo, to determine activation, presence of regulatory cells and memory cells. The Leishmania parasitemia and anti-Leishmania antibodies were determined respectively by qPCR and ELISA. Cells from individuals with VL under treatment showed less cell activation after stimulation with SLA for the markers CD4/CD69, CD8/CD69 and CD8/CD25 compared with VL post treatment treatment (p <0.001). Apparently uninfected individuals have a higher cell activation than symptomatic VL (p <0.001), with the exception of CD8/CD25 marker (p = 0.6662). On the other hand, in the ex-vivo group, significant differences were observed for CD4/CD69, CD8/CD69 and CD8/CD25 between the 4 groups due to increased cell activation present in cells of individuals symptomatic LV (p <0.001). VL cells under treatment, ex vivo, have a lower percentage of memory cells (CD4/CD45RO and CD8/CD45RO) than individuals VL post-treatment or control group (p = <0.01). Likewise, individuals with symptomatic VL have fewer regulatory cells when stimulated by SLA [CD4/CD25 (p = 0.0022) and CD4/FOXP3 (p = 0.0016)] and in the ex-vivo group (p = 0.0017). Finally, DNA isolated from recovered VL contained Leishmania DNA, supporting the hypothesis of non-sterile clinical cure for Leishmania infection. Recovered VL, even 10 years after treatment have high levels of memory cells, which may be due to the presence of stimulation, either by reexposure to Leishmania or non-sterile cure

O papel modulatório do ferro sobre a resposta imune na Leishmaniose Visceral

Iron is an essential element for many cellular functions, including the immune response against intracellular pathogens. In this study, we aimed evaluate the effect of iron on IRP2, IFN-γ, TNF-α, IL-6, IL-10, MIG and IP10 expression in PBMC and assess the effect of the spleen parasite load on the expression of these genes in the spleen of L. infantum naturally infected dogs. Blood sample from 7 DTH+ donor was collected and PBMC was obtained. The cells were cultivated in absence (iron chelator desferroximane, DFO 10 μM supplemented media) or in presence of iron (hemin 6 mM) for 1 h, followed by stimulation with Leishmania infatum antigen for 4 h. 44 dog spleen samples were obtained and parasite load in this organ was determinate by qPCR. Gene expression was analyzed by qPCR and cytokine production quantified by flow cytometry. In antigen stimulated cells, genes involved in immune response are significantly more expressed in presence of iron. T CD4+ and TCD8+ lymphocytes produces IFN-γ, TNF-α and IL-10 possibly in iron dependent pathway. Monocytes antigen stimulated reduced TNF-α, IL-6 and IL-10 production in presence of iron. We found spleen of infected dogs IRP2 expression increases according to parasite load in that organ, while an inverse profile was found for IFN-γ, TNF-α e IL-10 expression. These results suggest that T lymphocytes depends on iron to produce IFN-γ, TNF-α and IL-10, while iron seems to inhibit cytokine production in monocytes. So, we propose an immunoregulatory mechanism carried out by iron during L. infantum infection in humans and dogs

Periurbanização da leishmaniose visceral e emergência da coinfecção HIV/leishimania, no Rio Grande do Norte

Visceral leishmaniasis (VL) has undergone changes in terms of clinical and epidemiological presentation worldwide. Urbanization has been described in different regions of Brazil and the world, as well as in the state of Rio Grande do Norte. These changes have impacted in the clinical outcome of Leishmania infection. A new clinical entity called co-infection of HIV/Leishmania has been described as a consequence of overlapping areas of occurrence of VL and HIV / AIDS in different countries including Brazil. The aim of this study was to define the process of periurbanization of the LV and describe a case series of co-infection HIV / Leishmania in Rio Grande do Norte. A new demographic pattern of VL was detected, with an increase in the number VL adult male subjects. Analysis of spatial distribution of VL in the state of Rio Grande do Norte showed that in the past 20 years VL tends to occur in larger cities and therefore the highest risk disease is greater in the eastern and western regions. The first region included Natal, the state capital, where the process of suburbanization began in 1990, and more recently the city of Mossoró, the second largest state, where periurbanization began in the last five years. In 1990, the emergence of co-infection HIV/Leishmania in the state was observed. Case-control study revealed that the new clinical entity affects adult males, who acquired HIV through sexual intercourse, 40% of those with a preivous history of leishmania infection Relapse and death from LV is increased in HIV positive compared with HIV-negative patients matched by sex and age. This pattern is similar to the observed in Europe, except of the route of transmission, where in Europe occured concomitantly, by parenteral route in drug users. Analysis of spatial distribution identified overlapping new areas of occurrence of HIV / AIDS and LV potentially signaling to increased risk of this new clinical entity as described above. Therefore, epidemiological surveillance for co-infection HIV / Leishmania should be adopted in all areas of risk of VL. At the same time, it is necessary to evaluate drug resistance currently used in the treatment of VL, as well as parenteral transmission of L infantum/ chagasi in areas where drug dependence is a risk factor for HIV acquisition

Detecção de formas amastigotas em exame parasitológico de esfregaço obtido a partir de suabe conjuntival de cães com leishmaniose visceral

Leishmaniose é uma enfermidade multissistêmica cujas manifestações clínicas são extremamente variáveis. em cães sinais clínicos oftálmicos são relativamente frequentes, ainda que outros sinais sistêmicos não sejam identificados. Atualmente, o diagnóstico da doença baseia-se em métodos parasitológicos, sorológicos e moleculares, mas, até o momento, a identificação de formas amastigotas desse parasito em esfregaços feitos a partir de suabes conjuntivais não é empregada rotineiramente. Valendo-se de cães sorologicamente positivos para leishmaniose, portadores (G1) ou não (G2) de alterações oftálmicas, este estudo avaliou a viabilidade do esfregaço a partir de suabe conjuntival como método de diagnóstico para a enfermidade. O exame suprarreferido foi positivo em 60% dos animais do G1 e 38,1% do G2, no entanto não houve diferença estatisticamente significativa em relação à positividade nos dois grupos (P=0,2167). Os dados apontam para uma tendência de os cães com leishmaniose e com sinais oftálmicos serem positivos ao exame parasitológico de esfregaço a partir de suabe conjuntival, podendo esse método ser útil no diagnóstico parasitológico da leishmaniose canina.

Estudo comparativo dos métodos diagnósticos para Leishmaniose Visceral em cães oriundos de Ilha Solteira, SP

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exames parasitológicos, imunoistoquímicos e histopatológicos para detecção de Leishmania chagasi em tecidos esplênicos de cães com leishmaniose visceral

O propósito do presente trabalho foi o estudo da Leishmaniose Visceral Canina - LVC por meio de métodos parasitológicos e imunoistoquímicos para a detecção de formas amastigotas de Leishmania (L.) chagasi em baço, além de descrever a histopatologia das lesões esplênicas em 34 cães, com diferentes manifestações clínicas da LVC, eutanasiados pelo Centro de Controle de Zoonoses de Ilha Solteira, SP. Esses animais foram examinados clinicamente antes da eutánásia e de acordo com os sinais clínicos da LVC, foram classificados em três grupos: assintomáticos (8 cães), oligossintomáticos (17 cães) e sintomáticos (9 cães). Após a realização desses exames, dos 34 cães, 22 (64,7%) estavam positivos e 12 (35,3%) negativos. Desses cães positivos, 1/22 (4,5%) era assintomático, 12/22 (54,5%) eram oligossintomáticos e 9/22 (40,1%) sintomáticos. Pela histopatologia, os cães, especialmente os sintomáticos apresentavam o baço com inflamação crônica e espessamento na região capsular e trabecular, além de extensa alteração morfológica na polpa vermelha e branca pela presença de grande quantidade de macrófagos repletos de amastigotas, pela reação granulomatosa inflamatória e pelas áreas hemorrágicas. Os exames histopatológicos e a detecção microscópica direta da L. (L.) chagasi revelaram que o baço é um órgão útil para auxiliar no diagnóstico da LVC. A coloração imunoistoquímica foi a que detectou o maior número de tecidos esplênicos positivos com amastigotas, além de elucidar os casos suspeitos pelos exames parasitológicos, principalmente, nos animais assintomáticos ou oligossintomáticos.

Surto de leishmaniose tegumentar americana em Itaporanga, São Paulo (Brasil)

O presente trabalho relata os aspectos epidemiológicos e clínicos de surto de leishmaniose tegumentar americana na região Sudoeste do estado de São Paulo, área de colonização antiga, não associada a derrubadas de matas. Foram examinados 231 indivíduos, observando-se: a) Sessenta e sete indivíduos (29%) apresentavam leishmaniose confirmada pela histopatologia das lesões cutâneas e intradermorreação de Montenegro. Destes casos, 40 (59,7%) eram homens; b) a idade variou entre 2 (5 casos) e 86 anos (1 caso); c) de acordo com o tipo de lesão, observou-se: 54 (80, 6%) pacientes apresentavam úlceras, 13 (19,4%) nódulos, 4 (5,9%) lesões úlcero-vegetantes e 3 (4,4%) cicatrizes típicas; d) a intradermorreção de Montenegro apresentou 94,7% de positividade nos casos de leishmaniose-doença. Este estudo reforça observações prévias de que, além da forma clássica de transmissão, a leishmaniose pode ser transmitida no intra e peri-domicílio.

Comprometimento da pálpebra e via lacrimal excretora em portador de leishmaniose cutâneo-mucosa: relato de caso

Objetivo: Apresentar um portador de leishmaniose com lesão palpebral e dilatação de via lacrimal excretora. Relato de caso: O paciente em questão foi portador de leishmaniose do tipo cutâneo-mucosa, tendo apresentado múltiplas lesões de pele, ectrópio da pálpebra inferior, lesões na mucosa nasal e alterações na drenagem lacrimal. Discussão: O acometimento da pálpebra e da via lacrimal raramente ocorre em portadores de leishmaniose. Os autores chamam atenção para o diagnóstico e para a necessidade de se adotar medidas preventivas contra os vetores e a rápida instituição do tratamento.

Imunomarcação de células CD3+ e CD79a+ nas lesões descamativas e ulcerativas de cães com leishmaniose

Canine visceral leishmaniasis is an endemic infectious disease in some regions from São Paulo state and even though it is a systemic disease, in the dog, the main clinical sign is dermatological. Thirty dogs with positive results in serology (IFI) and parasitological exams (fine needle aspiration) for leishmaniasis from Aracatuba city were evaluated. They only showed dermatological signs and were divided in two groups, one with exfoliative (n=15) and other with ulcerative (n=15) lesions. There was significant statistical difference between CD3 and CD79a population in the same dermatological pattern, and with CD79a population between exfoliative and ulcerative patterns (p<0,05).

Diagnóstico da Leishmaniose Visceral Canina pelas técnicas de imunoistoquímica e PCR em tecidos cutâneos em associação com a RIFI e ELISA-teste

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação da leishmaniose visceral canina em Poxoréo, Estado do Mato Grosso, Brazil

O cão doméstico desempenha importante papel como reservatório na transmissão da leishmaniose visceral ao homem, zoonose de grande importância em saúde pública. Realizou-se avaliação epidemiológica da leishmaniose visceral em 1.112 cães domiciliados no município de Poxoréo, estado do Mato Grosso e observou-se prevalência de 7,8%. Observou-se ainda associação estatisticamente significativa entre a prevalência de leishmaniose visceral canina e as variáveis faixa etária, presença de sinais clínicos e presença de outra espécie animal co-habitando com os cães avaliados, tendo sido as galinhas mais freqüentemente observadas entre os animais soropositivos. O sexo, a coleta de lixo domiciliar bem como a renda familiar não apresentaram associação estatisticamente significativa com a prevalência da leishmaniose visceral canina. A análise dos resultados sugere que cães com idade superior a sete anos e a , presença de outra espécie animal co-habitando com os cães podem ser fatores de risco para a leishmaniose visceral canina.

Avaliação da reação em cadeia pela polimerase para diagnóstico da leishmaniose visceral em sangue de cães

Canine and human visceral leishmaniasis is endemic in several States of Brazil, and it is associated with infected dogs and the presence of the vector. Aiming at using polymerase chain reaction as a diagnostic tool in dogs, we amplified a 120bp fragment from kDNA of Leishmania spp. by PCR in blood samples. The lower detection limit observed was 0.1 parasites per 500 mu L of blood, which is a highly satisfactory result. on the other hand, PCR evaluation in 166 blood samples of dogs from Poxoreo, MS, Brazil, resulted in 55% sensitivity and 66.3% specificity, considering indirect imunnofluorescent test as gold standard.

Padrões histopatológicos das lesões descamativas e ulcerativas da pele em cães com leishmaniose

Canine visceral leishmaniasis is an endemic infectious disease in some São Paulo state regions and even though it is a systemic disease, in the dog, the main clinical sign is dermatological. Thirty dogs with positive results in serology and parasitological exams for leishmaniasis from Aracatuba city were evaluated. They just showed dermatological signs and were divided in two groups, one with exfoliative(n = 15) and other with ulcerative (n = 15) lesions. Histopathological. patterns in the group of exfoliative lesions were: periadnexial dermatitis (5115, 33,3%), superficial perivascular dermatitis (1/5, 6,6%), nodular dermatitis (1115, 6,6%) and mixed dermatitis (8/15, 53,3%), including intersticial/periadnexial dermatitis (1/8, 12,5%). lichenoid/perivascular superficial and deep dermatitis (1/8, 12,5%), perivascular superficial and deep/periadnexial dermatitis (1/8, 12,5%) and superficial perivascular/perianexial dermatitis (5/8, 62,5%). In the group of ulcerative lesions, the histopathological patterns were: perivascular superficial and deep dermatitis (5115, 33,3%), diffuse dermatitis (3/15. 20%), periadnexial dermatitis (2/15, 13,3%), nodular dermatitis (1/15, 6,6%) and mixed dermatitis (4/15, 26,6%), including intersticial/perivascular superficial and deep dermatitis (1/4, 25%), nodular/periadnexial dermatitis (1/4, 25%), fibrosing/perianexial dermatitis (1/4. 25%) and perivascular superficial and deep/periadnexial dermatitis(1/4, 25%). Parasites were found in eight dogs (8/15, 53,3%) with exfoliative dematitis and seven (7/15, 46,6%) with ulcerative dermatitis.