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.

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.

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.

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.

Slow clinical improvement after treatment initiation in Leishmania/HIV coinfected patients

INTRODUCTION: In Brazil there is a large area of overlap of visceral leishmaniasis (VL) and HIV infection, which favored a increased incidence of coinfection Leishmania/HIV. METHODS: This study evaluated 65 consecutive patients with VL and their clinical response to treatment in two health care settings in Belo Horizonte, Brazil. RESULTS: At baseline, the clinical picture was similar between both groups, although diarrhea and peripheral lymphadenomegaly were more frequent in HIV-infected subjects. HIV-positive patients had lower median blood lymphocyte counts (686/mm³ versus 948/mm³p = 0.004) and lower values of alanine aminotransferase (ALT) (48IU/L versus 75.6IU/L p = 0.016) than HIV-negative patients. HIV-positive status (hazard ratio = 0.423, p = 0.023) and anemia (HR = 0.205, p = 0.002) were independent negative predictors of complete clinical response following antileishmanial treatment initiation. CONCLUSIONS: This study reinforces that all patients with VL should be tested for HIV infection, regardless of their clinical picture. This practice would allow early recognition of coinfection with initiation of antiretroviral therapy and, possibly, reduction in treatment failure.

Comparison among three polymerase chain reaction assays on detection of DNA from Leishmania in biological samples from patients with american cutaneous leishmaniasis

INTRODUCTION: The study analyzed positivity of polymerase chain reaction (PCR) on detection of DNA from Leishmania in patients' samples. METHODS: Extracted DNA was submitted to L150/L152, 13Y/13Z, and seminested PCR (snPCR). RESULTS: Results were evidenced by bands of approximately 120, 720, and 670 bp for L150/L152, 13Y/13Z, and snPCR, respectively. L150/L152, 13Y/13Z, and snPCR positivity indexes were 76.9, 56.4, and 9.2 (p>0.05), respectively, for suspected and 93.7, 68.7, and 84.4 (p<0.05), respectively, for confirmed. CONCLUSIONS: Preliminary results showed that these assays, mainly L150/L152 and snPCR, can detect Leishmania DNA and carry potential on laboratory diagnosis of leishmaniasis.

Human immunodeficiency virus/Leishmania infantum in the first foci of urban American visceral leishmaniasis: clinical presentation from 1994 to 2010

INTRODUCTION:Human immunodeficiency virus (HIV) coinfection with Leishmania infantum or Leishmania donovani, the agents of visceral leishmaniasis (or kala-azar), has become a fatal public health problem in the tropics where kala-azar is endemic.METHODS:The clinical presentation of patients with HIV and L. infantum coinfection is described using two unique databases that together produce the largest case series of patients with kala-azar infected with HIV in South America. First, a retrospective study paired the list of all patients with kala-azar from 1994 to 2004 with another of all patients with HIV/AIDS from the reference hospital for both diseases in the City of Teresina, State of Piauí, Brazil. Beginning in 2005 through to 2010 this information was prospectively collected at the moment of hospitalization.RESULTS:During the study, 256 admissions related to 224 patients with HIV/L. infantum coinfection were registered and most of them were males between 20-40 years of age. Most of the 224 patients were males between 20-40 years of age. HIV contraction was principally sexual. The most common symptoms and signs were pallor, fever, asthenia and hepatosplenomegaly. 16.8% of the cohort died. The primary risk factors associated to death were kidney or respiratory failure, somnolence, hemorrhagic manifestations and a syndrome of systemic inflammation. The diagnosis of HIV and kala-azar was made simultaneously in 124 patients.CONCLUSIONS:The urban association between HIV and kala-azar coinfection in South America is worrisome due to difficulty in establishing the diagnosis and higher mortality among the coinfected then those with either disease independently. HIV/L. infantum coinfection exhibits some singular characteristics and due to its higher mortality it requires immediate assistance to patients and greater research on appropriate combination therapy.

Detection of antibodies against Leishmania infantum in cats (Felis catus) from the State of Pernambuco, Brazil

Introduction: Little information is available concerning infection by Leishmania infantum in cats. Therefore, the aim of this study was to perform a serological study in domestic cats. Methods: Serum samples (n=153) obtained from animals living in the Cities of Recife and Petrolina, State of Pernambuco, Brazil, were tested by ELISA/S7® (Biogene). Results: Anti-L. infantum antibodies were detected in 3.9% (6/153) of the cats. All seroreagent animals were from Petrolina. Conclusions: These results serve as an important alert, and future studies are needed to better understand the possible role of cats in the epidemiology of visceral leishmaniasis (VL) in this area.

Genes that encodes NAGT, MIF1 and MIF2 are not virulence factors for kala-azar caused by Leishmania infantum

IntroductionKala-azar is a disease resulting from infection by Leishmania donovani and Leishmania infantum. Most patients with the disease exhibit prolonged fever, wasting, anemia and hepatosplenomegaly without complications. However, some patients develop severe disease with hemorrhagic manifestations, bacterial infections, jaundice, and edema dyspnea, among other symptoms, followed by death. Among the parasite molecules that might influence the disease severity are the macrophage migration inhibitory factor-like proteins (MIF1 and MIF2) and N-acetylglucosamine-1-phosphotransferase (NAGT), which act in the first step of protein N-glycosylation. This study aimed to determine whether MIF1, MIF2 and NAGT are virulence factors for severe kala-azar.MethodsTo determine the parasite genotype in kala-azar patients from Northeastern Brazil, we sequenced the NAGT genes of L. infantum from 68 patients as well as the MIF1 and MIF2 genes from 76 different subjects with diverse clinical manifestations. After polymerase chain reaction (PCR), the fragments were sequenced, followed by polymorphism identification.ResultsThe nucleotide sequencing of the 144 amplicons revealed the absence of genetic variability of the NAGT, MIF1 and MIF2 genes between the isolates. The conservation of these genes suggests that the clinical variability of kala-azar does not depend upon these genes. Additionally, this conservation suggests that these genes may be critical for parasite survival.ConclusionsNAGT, MIF1 and MIF2 do not alter the severity of kala-azar. NAGT, MIF1 and MIF2 are highly conserved among different isolates of identical species and exhibit potential for use in phylogenetic inferences or molecular diagnosis.

The existence of only one haplotype of Leishmania major in the main and potential reservoir hosts of zoonotic cutaneous leishmaniasis using different molecular markers in a focal area in Iran

IntroductionLeishmania major is the causative agent of zoonotic cutaneous leishmaniasis (ZCL), and great gerbils are the main reservoir hosts in Iran. Abarkouh in central Iran is an emerging focal point for which the reservoir hosts of ZCL are unclear. This research project was designed to detect any Leishmania parasites in different wild rodent species.MethodsAll rodents captured in 2011 and 2012 from Abarkouh district were identified based on morphological characteristics and by amplification of the rodent cytochrome b (Cyt b) gene. To detect Leishmania infection in rodents, deoxyribonucleic acid (DNA) of each ear was extracted. Internal transcribed spacer-ribosomal deoxyribonucleic acid (ITS-rDNA), microsatellites, kinetoplast deoxyribonucleic acid (kDNA) and cytochrome b genes of Leishmania parasites were amplified by polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP) and sequencing were employed to confirm the Leishmania identification.ResultsOf 68 captured rodents in the region, 55 Rhombomys opimus were identified and nine Leishmaniainfections (9/55) were found. In addition, eight Meriones libycus and two Tatera indicawere sampled, and one of each was confirmed to be infected. Two Meriones persicus and one Mus musculuswere sampled with no infection.ConclusionsThe results showed that all 11 unambiguously positive Leishmania infections were Leishmania major. Only one haplotype of L. major(GenBank access No. EF413075) was found and at least three rodents R. opimus, M. libycus and T. indica—appear to be the main and potential reservoir hosts in this ZCL focus. The reservoir hosts are variable and versatile in small ZCL focal locations.

Coinfection by Toxoplasma gondii and Leishmania spp. in domestic cats (Felis catus) in State of Mato Grosso do Sul

Introduction Leishmaniasis and toxoplasmosis are important to public health. Methods Antibodies for Toxoplasma gondii and Leishmania spp. were evaluated in cats from Campo Grande, State of Mato Grosso do Sul, Brazil, a region endemic for canine visceral leishmaniasis. Serum samples from 50 asymptomatic cats were titrated for T. gondii by the immunofluorescence antibody test and modified agglutination test and for Leishmania spp. by the immunofluorescence antibody test. Results These two agents coinfected two (4%) of the 50 tested animals. Conclusions These findings demonstrate the concomitant presence of two important zoonoses in cats from Brazilian endemic regions for canine visceral leishmaniasis.