Leishmania braziliensis causing human disease in Northeast Brazil presents loci with genotypes in long-term equilibrium.

BACKGROUND: Leishmaniases are neglected tropical diseases that inflict great burden to poor areas of the globe. Intense research has aimed to identify parasite genetic signatures predictive of infection outcomes. Consistency of diagnostic tools based on these markers would greatly benefit from accurate understanding of Leishmania spp. population genetics. We explored two chromosomal loci to characterize a population of L. braziliensis causing human disease in Northeast Brazil. METHODOLOGY/PRINCIPAL FINDINGS: Two temporally distinct samples of L. braziliensis were obtained from patients attending the leishmaniasis clinic at the village of Corte de Pedra: (2008-2011) primary sample, N = 120; (1999-2001) validation sample, N = 35. Parasites were genotyped by Sanger's sequencing of two 600 base pairs loci starting at nucleotide positions 3,074 and 425,451 of chromosomes 24 and 28, respectively. Genotypes based on haplotypes of biallelic positions in each locus were tested for several population genetic parameters as well as for geographic clustering within the region. Ample geographic overlap of genotypes at the two loci was observed as indicated by non-significant Cusick and Edward's comparisons. No linkage disequilibrium was detected among combinations of haplotypes for both parasite samples. Homozygous and heterozygous genotypes displayed Hardy-Weinberg equilibrium (HWE) at both loci in the two samples when straight observed and expected counts were compared by Chi-square (p>0.5). However, Bayesian statistics using one million Monte-Carlo randomizations disclosed a less robust HWE for chromosome 24 genotypes, particularly in the primary sample (p = 0.04). Fixation indices (Fst) were consistently lower than 0.05 among individuals of the two samples at both tested loci, and no intra-populational structuralization could be detected using STRUCTURE software. CONCLUSIONS/SIGNIFICANCE: These findings suggest that L. braziliensis can maintain stable populations in foci of human leishmaniasis and are capable of robust genetic recombination possibly due to events of sexual reproduction during the parasite's lifecycle.

The miRNA 361-3p, a Regulator of GZMB and TNF Is Associated With Therapeutic Failure and Longer Time Healing of Cutaneous Leishmaniasis Caused by L. (viannia) braziliensis.

L. (viannia) braziliensis infection causes American Tegumentary Leishmaniasis (ATL), with prolonged time to healing lesions. The potent inflammatory response developed by the host is important to control the parasite burden and infection however an unbalanced immunity may cooperate to the tissue damage observed. The range of mechanisms underlying the pathological responses associated with ATL still needs to be better understood. That includes epigenetic regulation by non-coding MicroRNAs (miRNAs), non-coding sequences around 22 nucleotides that act as post-transcriptional regulators of RNAs encoding proteins. The miRNAs have been associated with diverse parasitic diseases, including leishmaniasis. Here we evaluated miRNAs that targeted genes expressed in cutaneous leishmaniasis lesions (CL) by comparing its expression in both CL and normal skin obtained from the same individual. In addition, we evaluated if the miRNAs expression would be correlated with clinical parameters such as therapeutic failure, healing time as well as lesion size. The miR-361-3p and miR-140-3p were significantly more expressed in CL lesions compared to normal skin samples (p = 0.0001 and p < 0.0001, respectively). In addition, the miR-361-3p was correlated with both, therapeutic failure and healing time of disease (r = 0.6, p = 0.003 and r = 0.5, p = 0.007, respectively). In addition, complementary analysis shown that miR-361-3p is able to identify with good sensitivity (81.2%) and specificity (100%) patients who tend to fail initial treatment with pentavalent antimonial (Sbv). Finally, the survival analysis considering "cure" as the endpoint showed that the higher the expression of miR-361-3p, the longer the healing time of CL. Overall, our data suggest the potential of miR-361-3p as a prognostic biomarker in CL caused by L. braziliensis.

Atypical Manifestations of Cutaneous Leishmaniasis in a Region Endemic for Leishmania braziliensis: Clinical, Immunological and Parasitological Aspects.

BACKGROUND: Atypical cutaneous leishmaniasis (ACL) has become progressively more frequent in Corte de Pedra, Northeast Brazil. Herein we characterize clinical presentation, antimony response, cytokine production and parasite strains prevailing in ACL. METHODOLOGY/PRINCIPAL FINDINGS: Between 2005 and 2012, 51 ACL (cases) and 51 temporally matched cutaneous leishmaniasis (CL) subjects (controls) were enrolled and followed over time in Corte de Pedra. Clinical and therapeutic data were recorded for all subjects. Cytokine secretion by patients' peripheral blood mononuclear cells (PBMC) stimulated with soluble parasite antigen in vitro, and genotypes in a 600 base-pair locus in chromosome 28 (CHR28/425451) of the infecting L. (V.) braziliensis were compared between the two groups. ACL presented significantly more lesions in head and neck, and higher rate of antimony failure than CL. Cytosine-Adenine substitutions at CHR28/425451 positions 254 and 321 were highly associated with ACL (p<0.0001). In vitro stimulated ACL PBMCs produced lower levels of IFN-γ (p = 0.0002) and TNF (p <0.0001), and higher levels of IL-10 (p = 0.0006) and IL-17 (p = 0.0008) than CL PBMCs. CONCLUSIONS/SIGNIFICANCE: ACL found in Northeast Brazil is caused by distinct genotypes of L. (V.) braziliensis and presents a cytokine profile that departs from that in classical CL patients. We think that differences in antigenic contents among parasites may be in part responsible for the variation in cytokine responses and possibly immunopathology between CL and ACL.

IFN-γ production to leishmania antigen supplements the leishmania skin test in identifying exposure to L. braziliensis infection.

BACKGROUND: Cutaneous leishmaniasis due to L. braziliensis (CL) is characterized by a positive delayed type hypersensitivity test (DTH) leishmania skin test (LST) and high IFN-γ production to soluble leishmania antigen (SLA). The LST is used for diagnosis of CL and for identification of individuals exposed to leishmania infection but without disease. The main aim of the present study was to identify markers of exposure to L. braziliensis infection. METHODOLGY/PRINCIPAL FINDINGS: This cohort study enrolled 308 household contacts (HC) of 76 CL index cases. HC had no active or past history of leishmaniasis. For the present cross-sectional study cytokines and chemokines were determined in supernatants of whole blood culture stimulated with SLA. Of the 308 HC, 36 (11.7%) had a positive LST but in these IFN-γ was only detected in 22 (61.1%). Moreover of the 40 HC with evidence of IFN-γ production only 22 (55%) had a positive LST. A total of 54 (17.5%) of 308 HC had specific immune response to SLA. Only a moderate agreement (Kappa = 0.52; 95% CI: 0.36-0.66) was found between LST and IFN-γ production. Moreover while enhancement of CXCL10 in cultures stimulated with SLA was observed in HC with DTH+ and IFN-γ+ and in patients with IFN-γ(+) and DTH(-), no enhancement of this chemokine was observed in supernatants of cells of HC with DTH(+) and IFN-γ(-). CONCLUSIONS/SIGNIFICANCE: This study shows that in addition of LST, the evaluation of antigen specific IFN-γ production should be performed to determine evidence of exposure to leishmania infection. Moreover it suggests that in some HC production of IFN-γ and CXCL10 are performed by cells not involved with DTH reaction.

Cutaneous leishmaniasis during pregnancy: exuberant lesions and potential fetal complications.

Cutaneous leishmaniasis affects millions of people worldwide. After observations of atypical lesions in pregnant women at the health centers of Corte de Pedra, Brazil, 9 years of records were reviewed, and 26 pregnant patients were identified. A retrospective case-control study revealed that lesions in pregnant women were much larger than those in nonpregnant patients in an age- and sex-matched group (mean area, 6.08 cm2 vs. 1.46 cm2; P=.008), and many lesions had an exophytic nature. Despite foregoing treatment until after delivery, response to pentavalent antimony therapy was favorable (rate of cure with 1 course of treatment, 85%). High rates of preterm births (10.5%) and stillbirths (10.5%) were reported. Cutaneous leishmaniasis during pregnancy produces distinct lesions and may have adverse fetal effects.

Plants used in treatment of leishmanial ulcers due to leishmania (viannia) braziliensis in an endememic area of Bahia, Brazil

This paper records the plants used in the treatment of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis (L(V)b) among the rural population of a cocoaproducing coastal area of Bahia state, Brazil. An enquiry conducted among a hundred patients identified 49 plant species used to treat skin ulceration caused by this Leishmania species. The principal plants used are caju-branco (Anacardium occidentale- Anacardiaceae), used by 65 per cent of the population, folha-fogo Clidemia hirta-Melastomataceae) 39 per cent, alfavaca-grossa Plectranthus amboinicus - Lamiaceae) 33 per cent, mastruz Chenopodium ambrosioides - Chenopodiaceae) 31 per cent, erva-de-santa-maria (Solanum americanum - Solanaceae) (25 per cent) and transagem (Plantago major - Plantaginaceae) 2 per cent.

Cura espontânea da leishmaniose causada por leishmania viannia braziliensis em lesöes cutâneas / Spontaneous healing of leishmaniasis caused by leishmania viannia braziliensis in cutaneous lesions

Os autores relatam que durante 14 anos de trabalho clínico em campo, realizado nas comunidades de Três Braços e Corte de Pedra, bahia, acompanharam 1.416 pacientes portadores de Leishmaniose Tegumentar Americana, cuja espécie envolvida na transmissäo, é predominamente a Leishmania Viannia brasilienses. A terapêutica utilizada rotineiramente nos casos é o antimoniato-N-metilglucamina (Glucantime). Contudo, 16 pacientes do sexo masculino recusaram-se a utilizar a medicaçäo e 6 do sexo feminino encontravam-se em período gestacional, portanto näo utilizaram o medicamento. Estes pacientes foram acompanhados por um período entre 4 a 12 anos, a partir do diagnóstico. observou-se que em 9 pacientes (40.9%) desta casuística, o tempo de cicatrizaçäo após o aparecimento da lesäo, pode ser calculado em 6 meses de evoluçäo. Quando se eleva a observaçäo para 12 meses, temos que 19 pacientes (86,3%) cicatrizaram suas lesöes neste período. Em 3 casos (13.6%) as lesöes permaneceram ativas por mais de 12 meses. Conclui-se que os determinantes da cicatrizaçäo natural das lesöes produzidas por Leishmania Viannia brasiliensis permanecem desconhecidos, dificultando para nós entedermos e compararmos aos efeitos das drogas utilizadas no tratamento da leishmaniose tegumentar

Procedência de pacientes portadores de leishmaniose tegumentar americana nas áreas endêmicas de três braços e corte de pedra, Estado da Bahia, Brasil / Origin of patients with american tegumentar leishmaniasis recorded in the endemic areas of Tres Braços and Corte de Pedra, Bahia State, Brazil

De acordo com o cadastro de 1416 pacientes portadores de leishmaniose tegumentar americana (L.T.A) referentes ao período de janeiro de 1976 a maio de 1987, os autores realizaram um levantamento da procedência dos casos dessa parasitose atendidos nas áreas endêmicas de Três Braços e Corte de Pedra no estado da Bahia. Os pacientes procediam de 24 dos 89 municípios que compöem a regiäo cacaueira da Bahia, destacando-se os municípios de Valença, Wenceslau Guimaräes e Teolândia como os de maior prevalência, somando juntos 923 casos (65,1%, com 520 destes residindo em umas poucas localidades contínuas entre si, formando uma área endêmica, com transmissäo ocorrendo provavelmente no peri, intradomicílio e nas lavouras de cacau e cravo localizadas nas encostas da floresta atlântica. Nota-se que a partir de 1983, houve um aumento do número de casos em toda a regiäo, havendo evidências da leishmaniose tegumentar americana comportar-se como uma doença ocupacional em toda a regiäo estudada

Leishmaniose causada por Leishmania viannia braziliensis (Lvb): um caso de evoluçäo atípica / Leishmania caused by Leishmania viannia braziliensis (Lvb): atypic evolution of a case

Os autores relatam o caso de uma criança portadora de Leishmaniose Tegumentar Americana causada por Leishmania braziliensis braziliensis que foi infectada durante a amamentaçäo, desenvolvendo lesäo infiltrativa e nodular nos lábios, com posterior disseminaçäo para os seis da face, fossas nasais e pavilhäo auricular e cuja evoluçäo clinica pós-terapêutica caracterizou-se por períodos sucessivos de regressäo e de reativaçäo da lesäo. Enfatizam a gravidade do caso, e as dificuldades terapêuticas com a utilizaçäo dos antimoniais pentavalentes, antimoniato-N-metil flucamina (Glucantime e o stibogluconato de sódio (Pentostam)