Pesquisa de infecção natural de flebotomíneos por Leishmania, no Estado do Paraná

A leishmaniose tegumentar americana tem sido notificada em todos os estados do Brasil e no Paraná essa doença é endêmica. O objetivo deste trabalho foi detectar a infecção natural de flebotomíneos para verificar a competência vetorial destes insetos e a identificação da espécie parasitária. Os flebotomíneos foram coletados com armadilhas de Falcão e Shannon, nos municípios de Doutor Camargo, Fênix e Mandaguari, de novembro de 2005 a agosto de 2006. Coletaram-se 12.930 flebotomíneos, dos quais 2.487 fêmeas foram dissecadas e destes 1.230 fêmeas foram submetidas à reação em cadeia da polimerase. Pelo método da dissecação, foi detectada uma fêmea de Nyssomyia whitmani com infecção natural por flagelados e pela reação em cadeia da polimerase não se detectou a presença de DNA de Leishmania em nenhuma das fêmeas. Apesar de não ter sido detectada a infecção natural de Nyssomyia neivai nas localidades em apreço e ainda que os requisitos de incriminação vetorial não tenham sido atendidos, não se deve negligenciar o potencial vetorial desta espécie.

Serological reactivity of different antigenic preparations of Leishmania (Leishmania) amazonensis and the Leishmania braziliensis complex

Total antigen from Leishmania (Leishmania) amazonensis and isolates from the Leishmania braziliensis complex, along with their respective antigenic fractions obtained by affinity chromatography on concanavalin-A-Sepharose and jacalin-agarose columns evaluated using immunoenzymatic ELISA assay. For this, serum samples from 229 patients were used, grouped as American tegmental leishmaniasis (nº=58), visceral leishmaniasis (nº=28), Chagas disease (nº=49), malaria (nº=32), tuberculosis (nº=13) and healthy volunteers (nº=49). Samples from American tegmentary leishmaniasis showed higher reactivity with antigens isolated from the Leishmania braziliensis complex than with antigens from Leishmania amazonensis (p<0.001). ELISA assays showed a sensitivity range from 60% to 95% with antigens isolated from the Leishmania braziliensis complex. There was marked nonspecific reactivity among serum samples with the use of antigenic fractions binding with concanavalin-A and jacalin from both Leishmania complexes, in comparison with other antigens (p<0.001). The results presented in this study suggest that the use of homologous antigens increases the efficiency of anti-Leishmania immunoglobulin detection, which may be very valuable for diagnostic purposes.

Estudo comparativo entre miltefosina oral e antimoniato de N-metil glucamina parenteral no tratamento da leishmaniose experimental causada por Leishmania (Leishmania) amazonensis

Vinte e cinco camundongos infectados com Leishmania amazonensis foram tratados com antimoniato de N-metil glucamina e miltefosina oral. Critérios: medidas das patas, pesquisa de amastigotas e culturas após-tratamento. Miltefosina: 2,43mm e glucamina 3,46mm (p=0,05). Miltefosina: esfregaços e culturas negativos. Glucamina: 2 esfregaços positivos e culturas positivas (p<0,05). Concluímos que miltefosina foi semelhante à glucamina.

Caracterização isoenzimática de isolados humanos de Leishmania sp (Kinetoplastida: Trypanosomatidae) dos municípios de Rio Preto da Eva e Manaus, Estado do Amazonas

Foram caracterizados/identificados por eletroforese de isoenzimas 23 isolados de Leishmania sp de pacientes dos municípios de Rio Preto da Eva e Manaus, analisando-se o grau de similaridade entre os organismos. Os resultados indicaram ocorrência de Leishmania guyanensis e Leishmania naiffi nestes dois ambientes e a heterogeneidade das amostras de Leishmania naiffi.

Avaliação sorológica para detecção de anticorpos anti-Leishmania em cães e gatos no bairro de Santa Rita de Cássia, Município de Barra Mansa, Estado do Rio de Janeiro

A partir de um caso canino de leishmaniose tegumentar americana na localidade de Santa Rita de Cássia, município de Barra Mansa, Rio de Janeiro, foi realizado um inquérito sorológico em 177 cães e 43 gatos. Na avaliação das amostras de soros caninos, 10% foram positivos na reação de imunofluorescência indireta e 10,7% no ensaio imunoenzimático. Entre as amostras de soros felinos testados, nenhum animal foi positivo na reação de imunofluorescência indireta e apenas um (2,4%) felino apresentou reação positiva ao ensaio imunoenzimático. A detecção de Leishmania braziliensis, autóctone em Barra Mansa, faz um alerta para a instalação de um possível foco de leishmaniose tegumentar americana nessa região.

Identificação de espécies de Leishmania isoladas de casos humanos em Mato Grosso do Sul por meio da reação em cadeia da polimerase

As leishmanioses são zoonoses endêmicas em Mato Grosso do Sul e têm por agentes etiológicos nessa região Leishmania (Leishmania) chagasi, Leishmania (Leishmania) amazonensis e Leishmania (Viannia) braziliensis. Como método para identificação de espécies de Leishmania, a reação em cadeia da polimerase é uma ferramenta com elevada especificidade e sensibilidade. Analisaram-se 39 isolados de Leishmania criopreservados, obtidos por meio de aspirado medular e/ou biópsia de lesão, conforme a suspeita clínica. Os isolados foram submetidos à extração de DNA e à reação em cadeia da polimerase com os iniciadores: RV1/RV2 para Leishmania (Leishmania) chagasi, a1/a2 para a identificação de Leishmania (Leishmania) amazonensis e b1/b2 para Leishmania (Viannia) braziliensis. Leishmania (Leishmania) chagasi foi a única espécie identificada em 37 casos de leishmaniose visceral. Leishmania (Leishmania) amazonensis foi identificada em dois isolados de pacientes com diagnóstico de leishmaniose tegumentar. Os resultados obtidos confirmam a possibilidade do uso dos três pares de iniciadores como uma ferramenta na caracterização de isolados de Leishmania.

Leishmania (Leishmania) infantum chagasi em canídeos silvestres mantidos em cativeiro, no Estado de Mato Grosso

INTRODUÇÃO: Leishmaniose visceral é uma zoonose que acomete diversos mamíferos tendo os canídeos domésticos como principais reservatórios em ambiente urbano. A presente nota descreve a infecção de canídeos silvestres por Leishmania (Leishmania) infantum chagasi mantidos em cativeiro no Estado de Mato Grosso, Brasil. MÉTODOS: De seis raposas (Cerdocyon thous) e um cachorro vinagre (Spheotos venaticus), foram coletadas amostras de pele, medula óssea e linfonodo para detecção e caracterização de Leishmania sp pela técnica de PCR-RFLP. RESULTADOS: Todos as animais pesquisados apresentaram-se positivos para Leishmania (L.) infantum chagasi. CONCLUSÕES: Destaca-se a importância de monitoramento adequado dos mesmos, além do maior controle desta enfermidade já que estes animais estão em ambientes de recreação pública.

Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania) amazonensis in the state of Mato Grosso do Sul, mid-western Brazil

INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3%) and Bi flaviscutellata (41.4%), present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania) amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.

Infecção natural de Lutzomyia (Lutzomyia) longipalpis (Diptera: Psychodidae) por Leishmania infantum chagasi em flebotomíneos capturados no município de Janaúba, Estado de Minas Gerais, Brasil

INTRODUÇÃO: A leishmaniose visceral tem sido notificada em quase todos os estados do Brasil, e principalmente no norte de Minas Gerais, onde a doença é endêmica. Este estudo visou detectar a infecção natural de Lutzomyia longipalpis e identificar através da técnica de PCR/RFLP a espécie de Leishmania encontrada nos flebotomíneos do município de Janaúba. MÉTODOS: Utilizando-se armadilhas luminosas, foram capturadas 1.550 fêmeas de L. longipalpis, que agrupadas em pool de 10 exemplares foram submetidas à extração e amplificação de DNA, através das técnicas de PCR genérico e cacofonia. RESULTADOS: Dos 155 pools, seis apresentaram-se positivos para Leishmania sp., sendo a taxa de infecção do município de 3,9%. Através da PCR/RFLP determinou-se que o padrão de digestão das amostras positivas foi semelhante ao da cepa referência Leishmania chagasi (MHOM/BR/74/PP75). CONCLUSÕES: A detecção de infecção natural associada a estudos sobre a epidemiologia da LV sugere que L. longipalpis esteja envolvida na transmissão de L. infantum chagasi em Janaúba, principalmente nas áreas de intensa transmissão de LV.

American cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis resistant to meglumine antimoniate, but with good response to pentamidine: a case report

This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesional infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia) braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.

Evaluation of Leishmania (Leishmania) chagasi strains isolated from dogs originating from two visceral leishmaniasis-endemic areas in Brazil using multilocus enzyme electrophoresis

INTRODUCTION: Domestic dogs are the most important reservoir in the peridomestic transmission cycle of Leishmania (Leishmania) chagasi. The genetic variability of subpopulations of this parasite circulating in dogs has not been thoroughly analyzed in Brazil, even though this knowledge has important implications in the clinical-epidemiological context. METHODS: The objective of this study was to evaluate and compare the phenotypic variability of 153 L. chagasi strains isolated from dogs originating from the municipalities of Rio de Janeiro (n = 57) and Belo Horizonte (n = 96), where the disease is endemic. Strains isolated only from intact skin were selected and analyzed by multilocus enzyme electrophoresis using nine enzyme systems (6PG, GPI, NH1 and NH2, G6P, PGM, MDH, ME, and IDHNADP). RESULTS: The electrophoretic profile was identical for all isolates analyzed and was the same as that of the L. chagasi reference strain (MHOM/BR/74/PP75). Phenetic analysis showed a similarity index of one for all strains, with the isolates sharing 100% of the characteristics analyzed. CONCLUSIONS: The results demonstrate that the L. chagasi populations circulating in dogs from Rio de Janeiro and Belo Horizonte belong to a single zymodeme.

Risk factors for Leishmania chagasi infection in an endemic area in Raposa, State of Maranhão, Brazil

INTRODUCTION: Infection with Leishmania chagasi is the most common clinical presentation for visceral leishmaniaisis in endemic areas. The municipality of Raposa is an endemic area in State of Maranhão, Brazil, and have had registration cases of visceral leishmaniasis disease. For this reason, a cross- sectional study was conducted to evaluate the risk factors for infection with L. chagasi detected by Montenegro skin test. METHODS: The sample comprised 96% of the inhabitants of the villages of Maresia, Pantoja, and Marisol located in the municipality of Raposa, corresponding to 1,359 subjects. Data were collected using a questionnaire. Univariate and multivariate logistic regression models were applied to evaluate the association between the variables studied and infection of L. chagasi. RESULTS: The variables associated with infection upon nonadjusted analysis were a straw roof, mud walls, floors of beaten earth, presence of sand flies inside or outside of the dwelling, and bathing outdoors. Adjusted analysis showed that the presence of sand flies inside/outside the dwelling was a risk factor, and age younger than 10 years was a protective factor against asymptomatic infection. CONCLUSIONS: The results highlight the extent to which precarious living conditions of the population strengthen the epidemiological chain of visceral leishmaniasis.

Characterization of Leishmania infantum species in dogs from the urban area of Cuiabá, State of Mato Grosso, Brazil

INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected canine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903) of Leishmania (Leishmania) infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L.) infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.

Diagnosis of Leishmania (Leishmania) chagasi infection in dogs and the relationship with environmental and sanitary aspects in the municipality of Palmas, state of Tocantins, Brazil

INTRODUCTION: The aim of the present study was to identify the presence of Leishmania (Leishmania) chagasi infection in dogs in the City of Palmas, Tocantins, Brazil, using the PCR technique to list the hot spots of infected dogs in the city and associate their occurrence to significant environmental changes at capture sites. METHODS: DNA was extracted from blood of dogs, and the PCR were performed with primers RV1/RV2. After screening the population studied, the regions of the city that had the highest occurrence of canine infection were detected. These sites were visited, and ecological parameters denoting anthropogenic disturbance were evaluated. RESULTS: Some important features were listed in the regions visited, such as low urbanization, lack of public collection of sewage, limited garbage collection, vacant lots with tall vegetation, decaying organic matter, and, most importantly, the occurrence of stray dogs and poultry in homes. CONCLUSIONS: The methodology for screening the population was very efficient, especially in evaluating a large number of individuals in a short time, with a high degree of automation. The results indicate an association between the observed parameters and the occurrence of infection in dogs. The model presented in the city is ideal for studies of disease progression and expansion and for the evaluation of control measures adopted for canine VL.

Clinical and laboratory alterations in dogs naturally infected by Leishmania chagasi

INTRODUCTION: Canine visceral leishmaniasis (CVL) is a zoonotic disease with different clinical manifestations. Parasitism often occurs in bone marrow, but changes have been observed in peripheral blood and serum biochemical parameters. The aim of this study was to evaluate the hematological and biochemical parameters in dogs naturally infected by Leishmania chagasi. METHODS: Eighty-five adult dogs of both sexes and various weights and ages from the Zoonosis Control Center of Fortaleza (CCZ) were used, selected by immunofluorescence assay (IFA) and considered positive with IFA titers greater than 1:40 and by visualizing amastigotes of Leishmania chagasi in smears obtained by bone marrow aspiration. The dogs (n = 85) were grouped according to clinical signs: negative (CN = 7), subclinical (CS = 10), and clinical (CC = 68). Blood samples were collected for determination of hematological and biochemical serum values. The experimental protocol was approved by the CEUA/UECE. RESULTS: The most frequent clinical signs were cachexia (77.9%), keratitis (61.8%), and lymphadenopathy (55.9%), and 86.8% of the animals showed more than one clinical sign characteristic of CVL. In CC were observed reductions in red blood cells (63%), hematocrit (72%), and hemoglobin (62%), as well as leukocytosis (33%), neutropenia (28%), thrombocytopenia (50%), uremia (45%), hyperproteinemia (53%, p<0.05), hypergammaglobulinemia (62%, p<0.01), and hypoalbuminemia (58%). CONCLUSIONS: Animals with the clinical form of the disease demonstrate hematological and biochemical changes consistent with anemia, uremia, hyperproteinemia, and hyperglobulinemia, which present themselves as strong clinical markers of visceral leishmaniasis associated with the signs previously reported.