Historical analysis of leishmaniasis cases in the transamazonian region: from 2009 to 2019

Objective: To determine the total number of notified cases, new cases and recurrence of American Tegumentary Leishmaniasis (ATL), to investigate the association between HIV coinfection and the presence of cutaneous lesion, as well to assess the concordance of two different laboratorial procedures: parasitological and histopathological in this region. Methods: This is a cross-sectional study. The research used data from the Information System for Notifiable Diseases, hence forth designated as SINAN (Sistema de Informação de Agravos de Notificação) that contained 6,183 cases of leishmaniasis in 9 municipalities. Results: As results, 5795 were of new cases and 351 recurrence cases. Among the cases 1,146 patients were tested for HIV, 16 presented coinfection from these 15 developed cutaneous lesion. In the overall studied population 5,690 subjects manifested cutaneous lesion. There was no agreement of the results regarding the quality of the parasitological and histopathological exams, demonstrating that they are poorly replicable (p <0.005). Conclusion: The ATL is endemic in the transamazonian region posing as a major public health problem. All patients with leishmaniasis must be tested for HIV and health professionals must register on the notification form. The tests to diagnose leishmaniasis need to be more specific and sensitive.

American Tegumentary Leishmaniasis in Montes Claros: an epidemiological study

Introduction: American Tegumentary Leishmaniasis (ATL), or kala azar, is a serious chronic disease caused by Leishmania spp. It is an infectious and non-contagious disease that affects both humans and several species of wild and domestic animals, presenting the clinical forms of cutaneous, mucocutaneous and diffuse cutaneous. ATL is classified as a generalized zoonotic disease that has a global impact. It is caused by protozoa of the genus Leishmania and is considered a serious public health problem. Objective: To describe the epidemiological profile of cases found in Montes Claros-MG. Methodology: An epidemiological assessment was performed based on secondary data from SINAN/MS from January 2010 to December 2015. Results: From 2010 to 2015, 286 cases of ATL were registered, with the majority of cases occurring in children under 19 years of age (31.81%) and patients over 59 years (17.83%) had a lower percentage of disease involvement. The first choice drug used by patients was Glucantime (87.06%). The most affected gender was male (52.44%) and most patients had no comorbidities (76.96%). Conclusion: In Montes Claros, Minas Gerais, ATL presented high cases during the research period. In this sense, this study guides the development of new researches that address and monitor the spread of the disease by monitoring urban areas concomitantly with the capture of animals for the presence of the parasite, thus assisting in public health decision-making in controlling the disease.

The Presence of Leishmania braziliensis DNA in the Nasal Mucosa of Cutaneous Leishmaniasis Patients and the Search for Possible Clinical and Immunological Patterns of Disease Progression: A Cross Sectional Study

Leishmania braziliensis is the most important causal agent of American tegumentary leishmaniasis (ATL), and 3 to 5% of patients develop mucosal lesions. The mechanisms related to parasite and host immune interactions and the parasite life cycle that lead to dissemination to the mucosa are poorly understood. We aimed to detect L. braziliensis DNA in the nasal mucosa of cutaneous leishmaniasis (CL) patients with early mucous dissemination and to relate those findings to specific inflammatory responses. Nasal swabs were collected from patients with the cutaneous form of ATL. L. braziliensis DNA was investigated using TaqMan-based real-time PCR. The levels of serum cytokines (IL-12, IL-6, TNF-α, IL-10, IL-1β and IL-8) were measured by a multiplex cytometric array. A Poisson regression model was used to test prevalence ratios (PRs) and multivariate interactions of clinical and laboratory characteristics. Of the 79 CL patients, 24 (30%) had L. braziliensis DNA in the nasal mucosa. In the multivariate model, parasite DNA presence in mucosa was associated with a reduction in IL-12 levels (PR = 0.440; p=0.034), increased IL-6 levels (PR = 1.001; p=0.002) and a higher number of affected body segments (PR = 1.65; p&lt;0.001). In this study, we observed a higher rate of early dissemination to the nasal mucosa than what was previously described. We suggest that an enhanced Th1 profile characterized by higher IL-12 is important for preventing dissemination of L. braziliensis to the mucosa. Further evaluation of parasite-related interactions with the host immunological response is necessary to elucidate the dissemination mechanisms of Leishmania.

Anthropogenic Dispersal of Leishmania (Viannia) braziliensis in the Americas: A Plausible Hypothesis

There are several gaps in our knowledge on the origin and spread of Leishmania (Viannia) braziliensis, an etiological agent of cutaneous and mucocutaneous or American tegumentary leishmaniasis, to different biomes, hosts, and vectors, with important epidemiological implications, including the possible existence of an anthroponotic component. Historical, biological, and epidemiological evidence suggests that Leishmania (V.) braziliensis and its variants were preexistent in Amazonia with great genetic variability, where they dispersed with less variability to other regions (clonal expansion). During pre-Columbian times the parasite may have been transported by migrating humans and probably also their dogs, from western Amazonia to the high inter-Andean valleys and from there to other regions of South America. The same thing could have happened later, in the same way, when it spread to non-Amazonian regions of Brazil and other countries of South and Central America, between the late 19th and early 20th centuries, during the so-called Rubber Boom and construction of the Madeira-Mamoré Railway in the Brazilian Amazon, by migrant workers who later returned to their places of origin, transporting the agent. The parasite’s dispersal in genetic correlated clusters, involving unexpectedly distinct ecosystems in Brazil (Amazonian, Cerrado, Caatinga and Atlantic Forest biomes), has continued until the present through human displacement. The infection of certain species of domestic, synanthropic and even wild animals, could be secondary to anthropogenic introduction of L. (V.) braziliensis in new environments. We admit the same phenomena happening in the probable transference of Leishmania infantum (visceral leishmaniasis), and of Yersinia pestis (plague) from the Old world to the New world, generating domestic and wild enzotic cycles from these agents. These assumptions associated with human infections, chronicity and parasite persistence with possibility of recovery of Leishmania in peripheral blood, skin and scars of cured or asymptomatic patients, (that may provide an alternative blood meal), along with the sand flies’ adaptation to the peri-domicile and the high susceptibility of domestic dogs, horses, mules and cats to the parasite, can reinforce the evidence of anthropogenic spread of L. (V.) braziliensis.

Serological study of American Tegumentary Leishmaniasis in working horses and contact dogs in the city of Bandeirantes, Parana

The American Tegumentary Leishmaniasis (ATL) occurs in several parts of the world, in Brazil and also in the State of Parana, it is a disease of great importance in public health, since it affects animals and humans, with a zoonotic character. Leishmaniasis is found in two forms, tegumentary and visceral, and has sandflies as vectors and wild animals and domestic dogs as reservoirs. ATL is considered an endemic disease in the city of Bandeirantes, with human cases occurring in several urban and rural locations, mainly in areas close to forest remnants, peri-urban and peripheral areas, where vulnerable populations live in general, and with precarious basic sanitation conditions. In these regions also live the participants of the wagon driver project, who own several working horses. The project provides guidance on management, good practices, disease prevention, and animal welfare. Since the role of horses as reservoirs and in the chain of transmission of ATL is not well known, the aim of this study was to carry out a serological study of ATL in horses and in the contact dogs of the participants of the " wagon driver" project, at UENP-CLM, to evaluate seropositivity in these species. Blood samples were collected from 20 horses and 12 contact dogs. A serological study, using the ELISAi test for ATL diagnosis, was carried out on the horses and dogs in relation to this study population, to assess seropositivity. In the serological survey, eight horses out of 20 animals (40%) and four dogs out of 12 animals (33.33%) were seropositive, a result considered significant, indicating the presence of the disease and the risk of transmission where they live. The occurrence of human cases and the presence of ATL vectors have already been identified in several locations in the city. Due to the lack of knowledge about the disease and the difficulty in controlling the vectors, health education is necessary in order to provide the population with orientation on how to prevent the disease, as well as entomological surveillance and new serological studies in areas at risk for ATL transmission. The results indicate that there may be importance in the role of horses as reservoirs and in the transmission of Tegumentary Leishmaniasis, which still needs to be clarified.

Epidemiological profile of american tegumentary leishmaniasis in the state of Maranhão in recent years

American Tegumentary Leishmaniasis (ATL) is a non-contagious disease, caused by a protozoan of the genus Leishmania, vector-borne by sandflies. Initially it is enzootic, but it can affect humans in a secondary way, characterizing itself as a zoonosis. It has great epidemiological importance due to the complexity of the treatment. The disease has been spreading on a large scale throughout Brazil, as well as in the state of Maranhão. This study is a descriptive approach with the use of confirmed cases of ATL by the Department of Informatics of the Unified Health System, for the years 2010 to 2019 for the state of Maranhão. The following variables were analyzed: annual notifications, gender, age group, clinical forms, case outcome and municipalities with the most notifications. During the study period, 19,043 cases were confirmed in the state. The year 2011 had the highest number of notifications, with 2,948 cases and an incidence of 44.83 cases per 100,000 inhabitants. The male gender was the most affected with 71.9%. The predominant age group was between 20 and 39 years old, with 42.7%. The cutaneous form was prevalent with 96.4%. The three municipalities with the highest number of records were Montes Altos (West Mesoregion), Buriticupu (West Mesoregion) and Arame (Centro Maranhense Mesoregion). The state of Maranhão is considered endemic for ATL, so it is considered essential to continuously adopt measures to combat the vector and to conduct educational campaigns that inform the population about minimizing the possibilities of disease transmission.

Serine proteases profiles of Leishmania (Viannia) braziliensis clinical isolates with distinct susceptibilities to antimony

Glucantime (SbV) is the first-line treatment against American Tegumentary Leishmaniasis. Resistance cases to this drug have been reported and related to host characteristics and parasite phenotypes. In this study, 12 Leishmania (Viannia) braziliensis isolates from patients that presented clinical cure (Responders—R) and relapse or therapeutic failure (Non-responders—NR) after treatment with antimony, were analyzed. These parasites were assessed by in vitro susceptibility to SbIII and SbV, serine proteases activity measured with substrate (z-FR-AMC) and specific inhibitors (TLCK, AEBSF and PMSF). In vitro susceptibility of axenic amastigotes to SbIII showed a significant difference between R and NR groups. The protease assays showed that TLCK inhibited almost 100% of activity in both axenic amastigotes and promastigotes while AEBSF inhibited around 70%, and PMSF showed lower inhibition of some isolates. Principal component and clustering analysis performed with these data yielded one homogeneous cluster with only NR isolates and three heterogeneous clusters with R and NR isolates. Additionally, differential expression of subtilisins (LbrM.13.0860 and LbrM.28.2570) and TXNPx (LbrM.15.1080) was evaluated in promastigotes and axenic amastigotes from both groups. The results showed a higher expression of LbrM.13.0860 and LbrM.15.1080 genes in axenic amastigotes, while LbrM.28.2570 gene had the lowest expression in all isolates, regardless of the parasite form. The data presented here show a phenotypic heterogeneity among the parasites, suggesting that exploration of in vitro phenotypes based on SbIII and serine proteases profiles can aid in the characterization of L. (V.) braziliensis clinical isolates.

A Pilot Randomized Clinical Trial: Oral Miltefosine and Pentavalent Antimonials Associated With Pentoxifylline for the Treatment of American Tegumentary Leishmaniasis

IntroductionAmerican tegumentary leishmaniasis (ATL), which can present as either cutaneous (CL) or mucosal leishmaniasis (ML), is endemic in South America, and first-line antimonial treatments are known for their wide range of adverse effects (AEs). Growing reports of drug resistance increase the urgency of the need for better treatment options. The objective of this pilot clinical trial was to assess the efficacy of and AEs associated with the oral combination of miltefosine and pentoxifylline based on a post hoc analysis.MethodsA pilot, randomized, open-label clinical trial was performed. The experimental group (M+P) received 50 mg twice a day (BID) miltefosine and 400 mg three times a day (TID) pentoxifylline, and the control group (A+P) received 20 mg Sb+V/kg/day intravenously and 400 mg TID pentoxifylline. Patients with ML received treatment for 28 days, and patients with CL received treatment for 20 days.ResultsForty-three patients were included: 25 with ML and 18 with CL caused by L.(V.) braziliensis. AEs were more frequent in the A+P group (p=0.322), and there was a need for treatment interruption due to severe AEs (p=0.027). Patients with CL had a higher chance of achieving a cure (p=0.042) and a higher risk of AEs (p=0.033). There was no difference in the chance of a cure based on the treatment (p=0.058).ConclusionIn this pilot randomized clinical trial, M+P treatment and A+P treatment yielded similar cure rates, and the former was associated with a lower risk of AEs. Future studies with more patients and longer follow-up are recommended.

miR-548d-3p Alters Parasite Growth and Inflammation in Leishmania (Viannia) braziliensis Infection

American Tegumentary Leishmaniasis (ATL) is an endemic disease in Latin America, mainly caused in Brazil by Leishmania (Viannia) braziliensis. Clinical manifestations vary from mild, localized cutaneous leishmaniasis (CL) to aggressive mucosal disease. The host immune response strongly determines the outcome of infection and pattern of disease. However, the pathogenesis of ATL is not well understood, and host microRNAs (miRNAs) may have a role in this context. In the present study, miRNAs were quantified using qPCR arrays in human monocytic THP-1 cells infected in vitro with L. (V.) braziliensis promastigotes and in plasma from patients with ATL, focusing on inflammatory response-specific miRNAs. Patients with active or self-healed cutaneous leishmaniasis patients, with confirmed parasitological or immunological diagnosis, were compared with healthy controls. Computational target prediction of significantly-altered miRNAs from in vitro L. (V.) braziliensis-infected THP-1 cells revealed predicted targets involved in diverse pathways, including chemokine signaling, inflammatory, cellular proliferation, and tissue repair processes. In plasma, we observed distinct miRNA expression in patients with self-healed and active lesions compared with healthy controls. Some miRNAs dysregulated during THP-1 in vitro infection were also found in plasma from self-healed patients, including miR-548d-3p, which was upregulated in infected THP-1 cells and in plasma from self-healed patients. As miR-548d-3p was predicted to target the chemokine pathway and inflammation is a central to the pathogenesis of ATL, we evaluated the effect of transient transfection of a miR-548d-3p inhibitor on L. (V.) braziliensis infected-THP-1 cells. Inhibition of miR-548d-3p reduced parasite growth early after infection and increased production of MCP1/CCL2, RANTES/CCL5, and IP10/CXCL10. In plasma of self-healed patients, MCP1/CCL2, RANTES/CCL5, and IL-8/CXCL8 concentrations were significantly decreased and MIG/CXCL9 and IP-10/CXCL10 increased compared to patients with active disease. These data suggest that by modulating miRNAs, L. (V.) braziliensis may interfere with chemokine production and hence the inflammatory processes underpinning lesion resolution. Our data suggest miR-548d-3p could be further evaluated as a prognostic marker for ATL and/or as a host-directed therapeutic target.