Resolvin D1 drives establishment of Leishmania amazonensis infection.

Previous studies have indicated that the balance between different eicosanoids reflect the intensity of the inflammatory profile in patients with tegumentary leishmaniasis. More recently, pro-resolution lipid mediators have been shown to play critical roles in dampening pathological inflammatory processes to reestablish homeostasis in a diverse range of experimental settings. Among these lipid mediator, resolvins from D series have been described as potent anti-inflammatory and immunomodulatory mediators, and its activities include inhibition of leukocyte chemotaxis and blockage production of proinflammatory cytokines, while increasing the expression of regulatory mediators. Whether resolvins play significant roles in establishment and persistence of Leishmania infection is currently unknown. We addressed this question in the current study by assessing circulating levels of D-series resolvins in tegumentary leishmaniasis patients presenting with localized or diffuse disease. We found heightened expression of resolvin D1 in diffuse cutaneous leishmaniasis which was correlated with expression profile of biomarkers associated with disease pathogenesis. Additional in vitro experiments using primary human macrophages indicated that resolvin D1 may promote intracellular Leishmania amazonensis replication through a mechanism associated with induction of heme oxygenase-1. These results suggest that targeting resolvin D1 could serve as potential strategy for host directed therapy in diffuse cutaneous leishmaniasis.

Repeated praziquantel treatments remodel the genetic and spatial landscape of schistosomiasis risk and transmission.

Repeated treatments with praziquantel reduce schistosomiasis prevalence and morbidity, but transmission persists and populations often recover within a few years. To identify factors associated with persistence, we surveyed and treated all identified Schistosoma mansoni infections in two rural Brazilian communities (Jenipapo and Volta do Rio) in 2009, 2012 and 2013. Eggs were collected from all infected individuals and genotyped with 11 microsatellite markers to evaluate parasite differentiation and diversity. After successive rounds of community-wide treatment, prevalence decreased from 45% to 24% then 16%. Intensity of infection decreased by 57% over this period, and the number of eggs transmitted to the environment decreased by 92%. During all time periods the majority of eggs were excreted by those >15years of age. The incidence was 23% in 2012 and 15% in 2013, consistent with a decrease in transmission. There was little immigration or gene flow over a distance of 6km. On reinfection, infrapopulations were moderately differentiated indicating that pretreatment multilocus genotypes were not fully reacquired. The effective population size responded to census population decline more rapidly than differentiation. Reinfection was concentrated in the downstream portion of Jenipapo, consistent with the observed increased human fecal contamination. At this scale and in this area S. mansoni infections exist on a fragmented landscape with a highly focal pattern of transmission that may facilitate future elimination.

Differential Expression of the Eicosanoid Pathway in Patients With Localized or Mucosal Cutaneous Leishmaniasis.

Unfettered inflammation is thought to play critical role in the development of different clinical forms of tegumentary leishmaniasis. Eicosanoids are potent mediators of inflammation and tightly associated with modulation of immune responses. In this cross-sectional exploratory study, we addressed whether targets from the eicosanoid biosynthetic pathway, assessed by multiplexed expression assays in lesion biopsy and plasma specimens, could highlight a distinct biosignature in patients with mucocutaneous leishmaniasis (MCL) or localized cutaneous leishmaniasis (LCL). Differences in immunopathogenesis between MCL and LCL may result from an imbalance between prostaglandins and leukotrienes, which may serve as targets for future host-directed therapies.

Arginase I, polyamine, and prostaglandin E2 pathways suppress the inflammatory response and contribute to diffuse cutaneous leishmaniasis.

Diffuse cutaneous leishmaniasis (DCL) is a rare clinical manifestation of tegumentary leishmaniasis. The molecular mechanisms underlying DCL pathogenesis remain unclear, and there is no efficient treatment available. This study investigated the systemic and in situ expression of the inflammatory response that might contribute to suppression in DCL. The plasma levels of arginase I, ornithine decarboxylase (ODC), transforming growth factor ß (TGF-ß), and prostaglandin E2 (PGE2) were higher in patients with DCL, compared with patients with localized cutaneous leishmaniasis (LCL) or with controls from an area of endemicity. In situ transcriptomic analyses reinforced the association between arginase I expression and enzymes involved in prostaglandin and polyamine synthesis. Immunohistochemistry confirmed that arginase I, ODC, and cyclooxygenase2 expression was higher in lesion biopsy specimens from patients with DCL than in those from patients with LCL. Inhibition of arginase I or ODC abrogates L. amazonensis replication in infected human macrophages. Our data implicate arginase I, ODC, PGE2, and TGF-ß in the failure to mount an efficient immune response and suggest perspectives in the development of new strategies for therapeutic intervention for patients with DCL.

Lesion size correlates with Leishmania antigen-stimulated TNF-levels in human cutaneous leishmaniasis.

Cutaneous leishmaniasis (CL) is a worldwide disease endemic in several regions of the globe. The hallmark of CL is skin ulcers likely driven by efforts of the immune system to control Leishmania growth. Cytokines, such as tumor necrosis factor (TNF) and interferon-gamma can control disease progression in animal models. Nevertheless, the impact of these cytokines in CL ulcer outcome is not well established in humans. In this study, 96 CL patients from an endemic area of Leishmania braziliensis were enrolled for a follow-up study that consisted of clinical and immunological evaluations in a 2-year period. Statistical analysis revealed that healing time (P = 0.029), age (P = 0.002), and TNF levels (P = 0.0002) positively correlate with ulcer size at the time of the first clinical evaluation. Our findings suggest that ulcer size correlates with healing time and TNF levels support the use of TNF inhibitors combined with standard therapy to improve healing in CL patients with severe lesions.

Schistosoma mansoni population structure and persistence after praziquantel treatment in two villages of Bahia, Brazil.

Praziquantel has been used to treat schistosome infections since 1979 and currently is the only chemotherapeutic agent in production for this purpose, raising concerns about the potential for the emergence of drug resistance. In practice, 10-20% of infected patients will continue to excrete eggs after treatment. It is not understood to what degree this represents selection of a resistant population or incomplete elimination due to the presence of immature worms at the time of treatment. We used a population genetics approach to test whether or not persistent Schistosomamansoni parasites were drawn from the same population as susceptible parasites. In this study, stool samples were collected from 96% of individuals in two small Brazilian communities (populations 482 and 367) and examined for S.mansoni eggs. The combined prevalence of S.mansoni infections in the villages was 41%. Total egg DNA was extracted from each sample and was genotyped at 15 microsatellite markers. Day-to-day variation of the infrapopulation from an individual human host was low (median differentiation using Jost's D=0.010), so that a single stool was representative of the genotypes present in stool eggs, at least in the short term. Average pairwise analysis of D among all pre-treatment infrapopulations suggested moderate differentiation (mean D=0.082 and 0.122 for the two villages), whereas the pre-treatment component population differentiation between the two communities was 0.047. The differentiation of the component population remaining after treatment from the fully susceptible component population was low (mean D=0.007 and 0.020 for the two villages), suggesting that the persistent parasites were not selected by praziquantel treatment. We will continue to follow these communities for evidence of selection or changes in population structure.

Efeito leishmanicida in vitro de Stachytarpheta cayennensis (Rich. ) Vahl (Verbenaceae) / In vitro leishmanicidal effect of Stachytarpheta cayennensis (Rich. ) Vahl (Verbenaceae)

A atividade anti-Leishmania do extrato hidroalcoólico de Stachytarpheta cayennensis, espécie utilizada popularmente no tratamento de lesões cutâneas causadas por Leishmania sp, foi testado em ensaios in vitro utilizando formas promastigotas de Leishmania braziliensis e L. amazonensis. O extrato hidroalcoólico foi preparado a partir das folhas secas e utilizado em culturas de L. amazonensis e L. braziliensis nas concentrações de 500 a 32,5 æg/mL. Após 24 horas as formas promastigotas foram quantificadas para o cálculo da CI50. A citotoxicidade do extrato foi avaliada também em culturas de macrófagos peritoneais. O extrato apresentou efeito leishmanicida dose e espécie-dependente para promastigotas de Leishmania sendo mais eficaz para L. braziliensis. O extrato não apresentou efeito citotóxico quando utilizado nas culturas de macrófagos. Concluiu-se que o extrato hidroalcoólico de S. cayennensis inibe formas promastigotas de Leishmania in vitro o que poderia justificar, pelo menos parcialmente, o uso popular dessa espécie no tratamento de úlceras causadas por Leishmania.

Leishmanicidal activity of the hydroalcoholic extract of Stachytarpheta cayennensis, species that is usually employed in ulcers caused by Leishmania, was evaluated in vitro using Leishmania braziliensis and L. amazonensis promastigotes forms. The hydroalcoholic extract was prepared from dried leaves and used in L. amazonensis and L. braziliensis promastigotes cultures at concentrations of 500 to 32.5 æg/mL. After 24 hours the promastigotes forms were quantified and the IC50 was calculated. The cytotoxicity of the extract was evaluated using peritoneal macrophages. The extract presented a dose and specie-dependent leishmanicidal effect to Leishmania promastigotes, mainly to the L. braziliensis ones. The cytotoxic effect was not observed in macrophage cultures. In conclusion, the hydroalcoholic extract of S. cayennensis inhibits the growing of Leishmania promastigotes forms in vitro accounting for the folk use of this vegetal in skin ulcers caused by Leishmania.

Experimental model of chronic osteomyelitis caused by Leishmania (L) amazonensis.

Experimental animal models have been used for the study of the physiopathogenesis of leishmaniasis, on some occasions with success, while in other situations such as bone alterations that accompany tegumentary leishmaniasis, especially in diffuse cutaneous form (DCL), the mechanisms are still unknown. In the present study, we determined these alterations in an animal model susceptible to Leishmania (L) amazonensis. Amastigotes of L. (L) amazonensis isolated from patients with diffuse cutaneous leishmaniasis (DCL) were inoculated into the hind paws of eight BALB/c mice, macroscopic and histopathological aspects were analyzed. After 90 and 120 days of evolution, histopathological analysis demonstrated a mononuclear cell infiltrate rich in plasma cells and intense parasitism of intra- and extra-medullary macrophages, with areas of bone necrosis and discrete involvement of cartilaginous tissue. The results show that the inflammatory process developed during L. (L) amazonensis infection might cause bone tissue destruction and secondarily affect the joints.

CD16+ monocytes in human cutaneous leishmaniasis: increased ex vivo levels and correlation with clinical data.

Peripheral blood CD16 (Fc receptor for immunoglobulin G III)-positive monocytes have been shown to expand in different pathological conditions, such as cancer, asthma, sepsis, human immunodeficiency virus infection, and AIDS progression, but data in leishmaniasis are lacking. We found that cutaneous leishmaniasis patients (n = 15) displayed a significant increase in the percentage (3.5 vs. 10.1) as well as mean fluorescent intensity (13.5 vs. 29.2) of ex vivo CD16 expression in monocytes as compared with healthy controls. We observed a significant positive correlation between the percentage of ex vivo CD16+ monocytes and lesion size (P = 0.0052, r = 0.75) or active transforming growth factor-beta plasma levels (P = 0.0017, r = 0.78). In addition, two patients with nonhealing lesions during a 3-year follow-up had high (9.1-19.4%) CD16 levels at diagnosis. Our data suggest a deleterious role for CD16 in human leishmaniasis, as well as its possible use as a marker for disease severity and/or adverse disease outcome.

Polymerase chain reaction (PCR) is highly sensitive for diagnosis of mucosal leishmaniasis.

We evaluated the use of polymerase chain reaction (PCR) for diagnosis of mucosal leishmaniasis (ML) in an endemic area in Acre, Brazil, where Leishmania braziliensis is present. Leishmania DNA was detected 34 of 35 cases, yielding a positivity rate of 97.1%, which was higher than the positivity rates for all of the other diagnostic methods studied, namely Montenegro skin test (MST), anti-Leishmania serological testing and microscopic examination of lesion biopsy specimens. These findings have led us to propose guidelines for the diagnosis of ML that use PCR as the principal method of parasitological confirmation of cases.

Uso de Cetoconazol® no tratamento da entomoftoromicose cutâneo-mucosa: relato de caso / Use of Ketoconazole for treating mucocutaneous Entomophthoromycosis: a case report

As entomoftoromicoses constituem entidade clínica pertencente ao grupo das zigomicoses, cujos agentes etiológicos são o Conidiobolus coronatus, Conidiobolos incongruus e o Basidiobolos ranarum. Um caso de entomoftoromicose cutâneo-mucosa é descrito em homem de 51 anos de idade, lavrador, procedente da região amazônica do Estado do Maranhão, Brasil. Teve diagnóstico esclarecido por exame anatomopatológico, um ano após as manifestações clínicas iniciais. Como tratamento utilizou-se um dos derivados imidazólicos (cetoconazol®) 400mg/dia divididos em duas tomadas, por 12 meses), mostrando boa tolerância, com resposta favorável. Na última avaliação, 24 meses após início do tratamento, encontrava-se clinicamente curado.

Clinical utility of polymerase chain reaction-based detection of Leishmania in the diagnosis of American cutaneous leishmaniasis.

We evaluated the use of polymerase chain reaction (PCR) for diagnosis of American cutaneous leishmaniasis (ACL) in an area in Bahia, Brazil, where Leishmania braziliensis is endemic. Leishmania DNA was detected in 50 cases, yielding a positivity rate of 100%, which was higher than the rates for all of the other diagnostic methods studied--namely, the Montenegro skin test, anti-Leishmania serological testing, and microscopic examination of lesion biopsy specimens. These findings have led us to propose guidelines for the diagnosis of ACL that use PCR as the principal means of parasitological confirmation of cases.

[Involvement of the renal function in patients with visceral leishmaniasis (kala-azar)]. / Envolvimento da função renal em pacientes com leishmaniose visceral (calazar).

UNLABELLED: Evaluation of the renal involvement of visceral leishmaniasis (kala-azar) aiming at verifying clinical and laboratorial repercussions of the renal implication on VL. Laboratory analysis was performed of blood and urine samples collected immediately after confirming diagnosis through the finding of Leishmania in bone marrow. Two (18.1%) patient presented complications associated with kala-azar. Five patients (45.4%) presented macroscopic hematuria and one case (N 9) clinical manifestations compatible with an acute nephritis syndrome. Laboratorial data of urine exam showed: proteinuria in 10 (90.9%) patients, hematuria in 7 (63.6%) and leukocyturia in 6 (54.5%) cases. Nine (81.8%) patients presented high levels of microalbuminuria, characterizing glomerular lesion. The presence of proximal tubulopathy, measured through retinol binding protein observed in 5 (45.4%) cases. CONCLUSION: renal involvement was manifested in most subjects, contributing to the severity of the disease.

Envolvimento da função renal em pacientes com leishmaniose visceral (calazar) / Involvement of the renal function in patients with visceral leishmaniasis (kala-azar)

Envolvimento da funçäo renal em pacientes com leishmaniose visceral (calazar). Apresenta-se estudo prospectivo de 11 pacientes com LV, com o intuito de verificar as repercussöes clínico-laboratoriais da funçäo renal na doença. Realizou-se análises laboratoriais das amostras de sangue e urina, colhidas logo após confirmaçäo diagnóstica, através do encontro de leishmanias no aspirado de médula óssea. Dois (18 por cento) pacientes apresentaram complicaçöes associadas a LV. Cinco (45,4 por cento) apresentaram hematúria macroscópica e em um caso (No.9) manifestaçöes clínicas compatíveis com síndrome nefrítica aguda. Os resultados dos exames de urina mostraram: proteinúria em 10 (90,9 por cento) pacientes, hematúria 7 (63,6 por cento) e leucocitúria em 6 (54,5 por cento) casos. Nove (81,8 por cento) pacientes apresentaram níveis elevados de microalbuminúria caracterizando lesäo glomerular. A presença de tubulopatia proximal medida através da proteína ligadora de retinol, foi observada em 5 (45,4 por cento) casos. Concluiu-se que o envolvimento renal se fez presente na maioria dos pacientes, contribuindo para a gravidade da doença

Obito durante tratamento da leishmaniose tegumentar americana com stibogluconato de sódio bp 88® (shandong xinhua) / Fatal case during treatment of american tegumentary leishmaniasis with sodium stibogluconate bp 88® (shandong xinhua)

Os autores relatam a ocorrência de óbito em paciente portador da forma cutânea da LTA no município de Caxias-MA. Trata-se de paciente do sexo masculino, 22 anos, gari, portador de lesäo ulcerada no membro inferior (perna esquerda), diagnosticado, após encontro do parasita (Leishmania) na lesäo, tratado com stibogluconato de sódio BP88® (Shandong Xinhua) na dose de 10mg/Sb+5/kg/dia/20 dias. Após a 3ª dose apresentou dores articulares, naúseas, mal estar geral. Com a continuaçäo da medicaçäo houve agravamento do quadro com dor epigástrica e no hipocôndrio direito irradiando-se para o hemitórax homolateral. Após a 7ª dose apresentou dispnéia associado à dor torácica de leve intensidade. Na 9ª dose houve piora do quadro, mesmo assim continuou a usar o medicamento até a 11ª dose quando seu estado agravou-se. Foi internado, necessitando de tratamento intensivo. Nos exames realizados apresentou: 4,4 milhöes de eritócitos, 10,6 por cento de hemoglobina, 35 por cento de hematócrito, 26.400 de leucócitos, basófilos e mielócitos (0), 59 por cento de segmentados, 30 por cento de linfócitos, 2 por cento de monócitos, plaquetas (normais), glicose 42mg por cento, uréia 73mg por cento, creatinina (2,4mg por cento), eletrocardiograma (bloqueio de ramo direito). Veio a falecer tendo como causa do óbito, insuficiência cárdio respiratória. O relato atual mostra a necessidade de esclarecimento das equipes de saúde quanto ao uso dos Sb+5 e também lembrar o Ministério da Saúde quando da aquisiçäo de novos produtos, preocupar-se com a qualidade e procedência do mesmo

Infecçäo por Leishmania (Leishmania) chagasi em crianças de uma área endêmica de leishmaniose visceral americana na Ilha de Säo Luís-MA, Brasil / Leishmania (Leishmania) chagasi infection on childhood from endemic area of visceral leishmaniasis in the Säo Luis-MA, island

Realizou-se estudo prospectivo com 648 crianças de zero a cinco anos no município da Raposa-MA, de julho/97 a junho/98, com o objetivo de avaliar as características da infecção por L.(L.)chagasi e verificar se existe associação entre desnutrição e infecção assintomática. Utilizou-se questionário com dados socioeconômicos, ambientais e hábitos de vida; realizou-se Intradermorreação de Montenegro(IDRM) com antígeno de L. amazonensis e Enzyme Linked Immunosorbant Assay(ELISA) para detectar infecção, e exame antropométrico. A prevalência inicial, final e incidência da infecção foram 18,6 por cento, 20,6 por cento e 10,8 por cento pelo IDRM, e 13,5 por cento, 34,4 por cento e 28 por cento pelo ELISA, respectivamente. A prevalência da desnutrição crônica (altura/idade) foi 26 por cento. Não houve associação estatisticamente significante entre desnutrição e infecção assintomática por L. (L.) chagasi. A forma assintomática da doença está presente nas áreas estudadas, necessitando de medidas de controle mais efetivas

Aspectos epidemiológicos determinantes na manutençäo da leishmaniose visceral no estado do Maranhäo - Brasil / The epidemiological determinant aspects in the maintenance of visceral leishmaniasis in the state of Maranhäo, Brazil

Analisou-se o comportamento da leishmaniose visceral (LV) no Estado do Maranhao-Brasil, no período de 1982 a 1993. A enfermidade vem ocorrendo predominantemente na Ilha de Sao Luís-MA em áreas periurbanas, destacando, no período epidêmico, a capital Sao Luís como principal área endêmica. A maior freqüênciade casos ocorreu em 1993, apesar do uso de inseticidas e controle dos caes. Houve predomínio na faixa etária de 0 a 4 anos de idade com 58,4 por cento dos casos. Nem a doença humana nem o índice pluviométrico apresentaram variaçoes sazonais significativas entretanto estiveram moderadamente correlacionados, havendo quase sempre elevaçao do número de casos após o período de maior precipitaçao chuvosa. A partir deste estudo, poderao ser levantadas questoes para o controle mais eficaz, consoante à urbanizaçao da doença, aliada aos fatores da dinâmica de trasmissao em áreas endêmicas do Estado.

Leishmaniose visceral no estado do Maranhäo, Brasil: a evoluçäo de uma epidemia / Visceral leishmaniasis in the state of Maranhäo, Brazil: evolution of an epidemic

Breve relato da evoluçäo histórica da leishmaniose visceral no estado do Maranhäo, Brasil, avaliando as possíveis causas da expansäo da referida doença no estado, assim como as medidas de controle adotadas pelo Ministério da Saúde, objetivando a diminuiçäo da incidência da mesma.

Spontaneous regional healing of extensive skin lesions in diffuse cutaneous leishmaniais (DCL)

The authors report a case of diffuse cutaneous leishimaniasis, with longstanding evolution and presenting with diffuse infiltrated lesions rich in amastigotes in the absence of mucosal involvement. In situ characterization with inonoclonal antibodies revealed Leishmania amazonensis. Large regional lesions have presented spontaneous healing without specific therapy. Considering that DCI presents with a defect in the cellular immune response, this fact demonstrate that this patient may develop a regional cellular immune response enough to destroy the parasites and to produce clearing of some lesions.