Leishmania amazonensis isolated from human visceral leishmaniasis: histopathological analysis and parasitological burden in different inbred mice.

Leishmania amazonensis is a major etiological agent of human cutaneous leishmaniasis in the Americas; nevertheless there are some reports of this species causing visceral disease in dogs and men. In the present work we have studied a Leishmania strain isolated from a human case of visceral leishmaniasis. We have infected different mouse strains and analyzed the development of the disease, studying the parasite's ability to visceralize and whether this ability is influenced by host genetics.

PCR associated with molecular hybridization detects Leishmania (Viannia) braziliensis in healthy skin in canine tegumentary leishmaniasis.

Tegumentary leishmaniasis (TL) is a zoonotic disease that affects humans and domestic dogs. In Brazil, TL is considered endemic, and Leishmania (Viannia) braziliensis is the prevalent species causing this disease. There is debate about the role of dogs (Canis familiaris) as domestic reservoirs in the transmission cycle of TL.

American tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis: assessment of parasite genetic variability at intra- and inter-patient levels.

Background: The genetic variability of Leishmania (Viannia) braziliensis was assessed at intra and interpatient levels of individuals with different clinical manifestations of American tegumentary leishmaniasis (ATL).

Methods: Fifty-two samples, of which 13 originated from cutaneous lesions and 39 from mucosal lesions, provided by 35 patients, were examined by low-stringency single-specific-primer PCR (LSSP-PCR) and phenetic analysis. Genetic variability of L.

Sylvatic and peridomestic populations of Triatoma pseudomaculata are not significantly structured by habitat, as revealed by two genetic markers.

Chagas disease remains a public health concern in Brazil and other Latin American countries, mainly due to the potential domiciliation of native triatomine species. We analyzed the genetic variability of Triatoma pseudomaculata in sylvatic and peridomestic ecotopes throughout three localities in the northeastern state of Bahia, Brazil. We studied polymorphisms generated by random amplified polymorphic DNA (RAPD) and isoenzyme electrophoresis analyses.

Eco-epidemiology of visceral leishmaniasis in the urban area of Paracatu, state of Minas Gerais, Brazil.

The present study was developed in the urban area of Paracatu, an endemic city for the American visceral leishmaniasis in Brazil. A six-month canine survey was performed with 6295 domiciled dogs in 28 districts in that area and showed that 4.2% of those (267 dogs) were positive for VL by ELISA and IFAT serum assays.

Phylogenetic and phenotypic relationships among Triatoma carcavalloi (Hemiptera: Reduviidae: Triatominae) and related species collected in domiciles in Rio Grande do Sul State, Brazil.

Triatoma carcavalloi is considered a rare Chagas disease vector often collected inside domiciles in Rio Grande do Sul State. In this Brazilian state, T. carcavalloi has been collected in the same ecotope (rock piles) with two other species (T.

Inferring from the Cyt B gene the Triatoma brasiliensis Neiva, 1911 (Hemiptera: Reduviidae: Triatominae) genetic structure and domiciliary infestation in the state of Paraíba, Brazil.

The Triatoma brasiliensis genetic structure was analyzed using the Cyt B gene in different geographic locations and ecotopes after a short and long period after insecticide treatment. Four different localities (16-40 km apart) in the state of Paraíba, Brazil, were sampled. Analysis of molecular variance (AMOVA) showed that grouping populations according to the geographic location or ecotope resulted in a higher variance among populations within groups (Phi(SC) ranging from 0.

Infectivity of seropositive dogs, showing different clinical forms of leishmaniasis, to Lutzomyia longipalpis phlebotomine sand flies.

Visceral leishmaniasis (VL) is a growing zoonosis with an increasing number of new cases and a rapid geographical spreading of the disease. In the present study, a canine survey was carried out in the city of Montes Claros (320,000 inhabitants), an endemic area of American visceral leishmaniasis in the state of Minas Gerais, Brazil. A total number of 4795 dogs were examined by serology, which showed a rate of seropositivity of 5%.

[Biological and molecular characteristics of uropathogenic Escherichia coli strains isolated in the city of Rio de Janeiro].

Uropathogenic Escherichia coli strains isolated from individuals living in different areas of the city of Rio de Janeiro were characterized according to serotype, hemolytic properties, hemagglutination properties, antimicrobial susceptibility and isoenzymatic profile. The molecular approach used, together with investigation of urovirulence markers, enabled detection of great diversity among the isolates. However, closer relationships were observed between epidemiologically related Escherichia coli samples.

Genetic heterogeneity in Trypanosoma cruzi strains from naturally infected triatomine vectors in northeastern Brazil: epidemiological implications.

Eighteen Trypanosoma cruzi strains isolated from naturally infected triatomines were studied genetically. The majority of the strains were from Triatoma brasiliensis, the principal vector of Chagas disease in the northeast of Brazil. Multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) analyses were used to investigate the genotypic diversity and the spread of the T.

Response to Silva et al.: Usefulness of PCR-based methods for screening Leishmania in epidemiological studies.

The detection of Leishmania in naturally infected rodents in endemic areas is of fundamental importance for defining these rodents as possible reservoir hosts of infection. The use of polymerase chain reaction in conjunction with molecular hybridization has provided important results that could lead to a better understanding of the natural history of leishmaniasis.

Triatoma rubrovaria (Blanchard, 1843) (Hemiptera-Reduviidae-Triatominae) IV: bionomic aspects on the vector capacity of nymphs.

Triatoma rubrovaria has become the most frequently captured triatomine species since the control of T. infestans in the state of Rio Grande do Sul (RS), Brazil. The aim of this study was to evaluate aspects of the vectorial competence of T.

Application of direct agglutination test (DAT) and fast agglutination screening test (FAST) for sero-diagnosis of visceral leishmaniasis in endemic area of Minas Gerais, Brazil.

Background: The direct agglutination test (DAT) has proved to be a very important sero-diagnostic tool combining high levels of intrinsic validity and ease of performance. Otherwise, fast agglutination screening test (FAST) utilises only one serum dilution making the test very suitable for the screening of large populations.

Results: We have tested FAST and DAT for the detection anti-Leishmania antibodies in serum samples from patients with American visceral (AVL) and cutaneous leishmaniases (ACL) in Minas Gerais State, Brazil.

PCR-based diagnosis for detection of Leishmania in skin and blood of rodents from an endemic area of cutaneous and visceral leishmaniasis in Brazil.

The technique of polymerase chain reaction (PCR) associated to hybridization was used to screen 123 samples collected from wild and synanthropic rodents captured in a cutaneous and visceral leishmaniasis endemic area in the State of Minas Gerais, Brazil. The detection of Leishmania spp in naturally infected rodents is of fundamental importance for incriminating them as possible reservoir hosts of the diseases in Minas Gerais. A total of 62 specimens belonging to wild (Thrichomys apereoides, Oryzomys subflavus, Galea spixii, Bolomys lasiurus and Wiedomys pyrrhorhinos) and synanthropic (R.

Chagas disease and HIV co-infection: genetic analyses of two Trypanosoma cruzi strains under experimental immunosuppression.

BACKGROUND: Recently new aspects of the immunopathology of Chagas disease have been described in patients infected with HIV and unusual clinical manifestations such as cutaneous lesions, involvement of central nervous system and/or serious cardiac lesions related to the reactivation of the parasite have been reported. Two uncloned Trypanosoma cruzi strains previously isolated from chronic chagasic patients with HIV co-infection were studied in order to evaluate the impact of the immunosuppression on the genetic diversity of the parasite. RESULTS: We have exploited an experimental model to determine whether genetically distinct populations appear after immunosuppression as a consequence of in vivo selection or in vitro propagation.

Triatoma rubrovaria (Blanchard, 1843) (Hemiptera-Reduviidae-Triatominae) III: patterns of feeding, defecation and resistance to starvation.

Data from the Chagas Disease Control Program indicate a growing domiciliary and peridomiciliary invasion of Triatoma rubrovaria in the State of Rio Grande do Sul, where it has become the most frequent triatomine species captured there since the control of T. infestans. Bionomic characteristics that could influence the vectorial capacity of T.

Triatoma rubrovaria (Blanchard, 1843) (Hemiptera, Reduviidae, Triatominae) II: trophic resources and ecological observations of five populations collected in the State of Rio Grande do Sul, Brazil.

Triatoma rubrovaria has become the most frequently captured triatomine species after the control of T. infestans in the State of Rio Grande do Sul (RS), Brazil. Isoenzymatic and chromatic studies indicate the existence of, at least, two distinct phenotypic patterns of T.

Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) I: isoenzymatic and chromatic patterns of five populations from the State of Rio Grande do Sul, Brazil.

Triatoma rubrovaria has become the most frequently captured triatomine species since the control of T. infestans in the State of Rio Grande do Sul (RS), Brazil. In order to evaluate the genetic variability of this species, field collections were performed in four municipalities where it has been reported and distant from 75 to 322 km.

Concurrent cutaneous, visceral and ocular leishmaniasis caused by Leishmania (Viannia) braziliensis in a kidney transplant patient.

Although cases of leishmaniasis co-infection have been described in acquired immunodeficiency syndrome patients as well as those who have undergone organ transplants, to our knowledge, the present report is the first documented case of simultaneous cutaneous, visceral and ocular leishmaniasis due to Leishmania (Viannia) braziliensis in a transplant patient. The patient had been using immunosuppressive drugs since receiving a transplanted kidney. The first clinical signs of leishmaniasis included fever, thoracic pain, hepatosplenomegaly, leucopenia and anemia.

Visceral leishmaniasis caused by Leishmania (Viannia) braziliensis in a patient infected with human immunodeficiency virus.

The current article reports the case of a 19-month-old-girl, from the state of Minas Gerais, Brazil, with visceral leishmaniasis, by Leishmania (Viannia) braziliensis, and Human Immunodeficiency Virus (HIV) co-infection. The child's mother and father, aged 22 and 27 years old, respectively, were both HIV positive. The child was admitted to the General Pediatric Center, in Belo Horizonte, presenting high fever, fatigue, weight loss and enlargement of liver and spleen.