Clinical and epidemiological features of leishmaniasis in northwestern-Argentina through a retrospective analysis of recent cases

Is leishmaniasis the new emerging zoonosis in the world?

Leishmania is a genus of parasitic protozoa that causes a disease called leishmaniasis. Leishmaniasis is transmitted to humans through the bites of infected female sandflies. There are several different species of Leishmania that can cause various forms of the disease, and the symptoms can range from mild to severe, depending on species of Leishmania involved and the immune response of the host. Leishmania parasites have a variety of reservoirs, including humans, domestic animals, horses, rodents, wild animals, birds, and reptiles. Leishmaniasis is endemic of 90 countries, mainly in South American, East and West Africa, Mediterranean region, Indian subcontinent, and Central Asia. In recent years, cases have been detected in other countries, and it is already an infection present throughout the world. The increase in temperatures due to climate change makes it possible for sandflies to appear in countries with traditionally colder regions, and the easy movement of people and animals today, facilitate the appearance of Leishmania species in new countries. These data mean that leishmaniasis will probably become an emerging zoonosis and a public health problem in the coming years, which we must consider controlling it from a One Health point of view. This review summarizes the prevalence of Leishmania spp. around the world and the current knowledge regarding the animals that could be reservoirs of the parasite.

Severe mucosal leishmaniasis with torpid and fatal evolution

Mucosal leishmaniasis is a clinical condition that is difficult to diagnose and treat and usually precedes a cutaneous leishmaniasis condition with a long latency period as observed in our study of a patient who experienced a torpid evolution in 9 months, caused by having had cutaneous leishmaniasis on the neck without therapeutic treatment, although with ulcer closure 18 years earlier, incomplete treatment with antimonials and amphotericin B, with the destruction of the eyeball, a large area of necrosis on the face and nasal bone exposure. Additionally, the patient had chronic anemia (9.4 g/dl), lymphopenia and neutrophilia (lymphocytes 13.1%, neutrophils 84.4%), and co‐infections by fungi (yeasts and hyphae) and Gram‐negative bacteria (multidrug‐resistant Proteus mirabilis and Escherichia coli) leading to sepsis and subsequent death of the patient.

Transfer of parasitology research to patents worldwide

Mankind has known about different parasitic diseases since ancient times. There is no doubt that parasites are the infectious agents that have caused the most deaths throughout history. But even today, parasitic diseases affect more than one billion people worldwide. In this paper, the relationship between articles published in the area of parasitology and international patents in this field from 1996 to 2019 was analyzed. For this purpose, Scopus has been used. This is a database developed by Elsevier, which, in addition to having numerous indexed journals and books, has developed SciVal, an analysis tool with which the publications that have been cited in the patents of the 5 largest patent offices in the world have been analyzed. The analysis has allowed us to study 2814 publications, to know their time trend, their Authors, Affiliations, and Countries, as well as the journals in which they have been published. Also, the topics and topic clusters related to parasitology that appear in publications cited in international patents have been known. Thus, the existence of six Topic Clusters that group 94% of all publications has been discovered. Of all of them, the Topic Cluster referring to malaria stands out above all others, with 968 articles (34% of the total), probably due to the fact that malaria continues to be, to this day, one of the great challenges for both industry and basic research throughout the world.

Leishmania and its relationships with bacteria

Leishmaniasis is a zoonotic and neglected disease, which represents an important public health problem worldwide. Different species of Leishmania are associated with different manifestations, and a practical problem that can worsen the condition of hosts infected with Leishmania is the secondary infection caused by bacteria. This review aims to examine the importance and prevalence of bacteria co-infection during leishmaniasis and the nature of this ecological relationship. In the cases discussed in this review, the facilitation phenomenon, defined as any interaction where the action of one organism has a beneficial effect on an organism of another species, was considered in the Leishmania-bacteria interaction, as well as the effects on one another and their consequences for the host.

[Tegumentary leishmaniasis and sandflies in Colonia Santa Rosa locality in northern Argentina]

Tegumentary leishmaniasis (TL) is caused by parasites of the genus Leishmania and transmitted by the sandfly species, insects belonging to the order Diptera, family Psychodidae. Historically, the most endemic area of TL in Argentina has been the northern region. The aim of this work was to analyze the presence and temporal variation of TL cases reported between 1985 and 2019 in Colonia Santa Rosa locality, northern Argentina. Furthermore, its clinical forms were characterized and sandflies were captured. Patients were diagnosed by smear and the Montenegro skin test. For sampling, CDC light traps were placed at 14 sites from 7pm to 7am. The correlation between vegetation cover and sandfly abundance was also studied. One hundred and twenty TL cases were diagnosed and the overall prevalence was 0.75% (≈16 000 inhabitants). Patients presented simple and multiple cutaneous leishmaniasis (88.79%) and the mucocutaneous form (10.83%). Skin lesions were more frequent on the lower extremities (46.73%). Of the total number of sandflies, Nyssomyia neivai (95%) was the predominant species followed by Migonemyia migonei (1.9%), cortelezzii complex (1.3%) and Evandromyia sallesi (0.09%). The persistent occurrence of cases and the presence of sandflies in the locality suggest the existence of endemic transmission in the area. This highlights the need to design prevention and control measures for TL in northern Argentina.

Evaluation of a point-of-care molecular detection device for Leishmania spp. and intercurrent fungal and mycobacterial organisms in Peruvian patients with cutaneous ulcers

PURPOSE

Overlapping clinical features of cutaneous leishmaniasis (CL) with ulcers caused by fungi and mycobacteria necessitate confirmatory diagnostic testing. We evaluated a handheld battery-operated device for detection of CL and common fungal and mycobacterial causes of ulcers.

METHODS

We validated Palm PCR™ for detection of common ulcerative skin pathogens using ATCC^® reference and clinical strains of Leishmania, mycobacteria, and fungi in the lab and field. Amplified products were Sanger sequenced. Performance characteristics were calculated using conventional PCR as a reference standard.

RESULTS

Palm PCR™ detected 100% of ATCC^® strains of Leishmania, fungi, and mycobacteria, with sensitivity and specificity of 90% and 91.7%, respectively. In the field, the sensitivity for detection of Leishmania in patients with suspected CL was 100%. In 61% of CL patients, co-colonization with genera such as Malassezia, Aspergillus, Candida, and Cladosporium was detected. In 50% of CL patients with an inflammatory (secondarily infected) phenotype, detected fungal species had known associations with human cutaneous disease.

CONCLUSIONS

Palm PCR™ performs comparably to conventional PCR for detection of Leishmania, fungi, and mycobacteria. This work has implications for the diagnostic approach to tropical ulcers, and has the potential to improve field detection of ulcerative pathogens in resource constrained areas.

Clinical and immunological characteristics of tegumentary leishmaniasis cases in Bolivia

BACKGROUND

Tegumentary leishmaniasis (TL) is a parasitic disease that can present a cutaneous or mucocutaneous clinical form (CL and MCL, respectively). The disease is caused by different Leishmania species and transmitted by phlebotomine sand flies. Bolivia has one of the highest incidences of the disease in South America and the diagnosis is done by parasitological techniques. Our aim was to describe the clinical and immunological characteristics of CL and MCL patients attending the leishmaniasis reference center in Cochabamba, Bolivia, in order to gain updated clinical and epidemiological information, to evaluate the diagnostic methods used and to identify biomarkers related to clinical disease and its evolution.

METHODOLOGY/PRINCIPAL FINDINGS

The study was conducted from September 2014 to November 2015 and 135 patients with lesions compatible with CL or MCL were included. Epidemiological and clinical data were collected using a semi-structured questionnaire. Two parasitological diagnostic methods were used: Giemsa-stained smears and culture of lesion aspirates. Blood samples obtained from participants were used to measure the concentrations of different cytokines. 59.2% (80/135) were leishmaniasis confirmed cases (CL: 71.3%; MCL: 28.7%). Sixty percent of the confirmed cases were positive by smears and 90.6% were positive by culture. 53.8% were primo-infections. Eotaxin and monokine induced by IFN-γ presented higher serum concentrations in the MCL clinical presentation compared to CL cases and no-cases. None of the cytokines presented different concentrations between primo-infections and secondary infections due to treatment failure.

CONCLUSIONS/SIGNIFICANCE

In Bolivia, parasitological diagnosis remains the reference standard in diagnosis of leishmaniasis because of its high specificity, whereas the sensitivity varies over a wide range leading to loss of cases. Until more accurate tools are implemented, all patients should be tested by both smears and culture of lesion aspirates to minimize the risk of false negatives. Our results showed higher concentrations of several cytokines in MCL compared to CL, but no differences were observed between CL and no-cases. In addition, none of the cytokines differed between primary and secondary infections. These results highlight the need of further research to identify biomarkers of susceptibility and disease progression, in addition to looking at the local cellular immune responses in the lesions.

Risk factors for antimony treatment failure in American Cutaneous Leishmaniasis in Northwestern-Argentina

BACKGROUND

To date, there is no specific literature available on the determinants for therapeutic failure (TF) with meglumine antimoniate (MA) in Northwestern-Argentina. This study aimed to identify epidemiological, clinical, and treatment-related factors that could be involved in TF.

METHODOLOGY/PRINCIPAL FINDINGS

We performed a case-control study. Cases were represented by patients who showed TF after administration of the first course of MA treatment, whereas, controls were determined as patients who evolved towards healing after the first MA cycle received. Crude Odds Ratios and their corresponding 90% confidence intervals (CI) were calculated, and risk factors were then tested by multivariate analysis using logistic binary regression. Three hundred and eighty-four patients with a presumptive diagnosis of ACL were recruited, and 153 with a positive diagnosis were selected. We included in the study 71 patients, who underwent specific treatment with MA, presented complete data on response to treatment, and had a minimum post-treatment follow-up of 6 months in cutaneous leishmaniasis, and 12 months in mucosal leishmaniasis. Of these, 34 (47.9%) presented TF. In the initial analysis, TF was significantly associated with the geographical area of disease acquisition (p = 0.036), the presence of mucosal lesions (p = 0.042), the presence of concomitant skin and mucosal lesions (p = 0.002), and lesion age ≥ 6 months (p = 0.018). Risk factors influencing TF in the final multivariate model included the geographical area where the disease was acquired (adjusted Odd Ratio 8.062; 95% CI 1.914-33.959; p = 0.004), and lesion age ≥ 6 months (adjusted Odd Ratio 10.037; 95% CI 1.383-72.843; p = 0.023).

CONCLUSIONS/SIGNIFICANCE

The results of the present study suggest the existence of some risk factors linked to TF in Northwestern-Argentina, which deserve further investigation. Herein we recorded a high percentage of TF and we described clinical and epidemiological characteristics associated with TF that could be taken into account improving the clinical management of patients.

Clinical and epidemiological profiles of patients with American cutaneous leishmaniasis from the states of Pernambuco and Amazonas, Brazil

INTRODUCTION:

Brazil has a high number of cases of American cutaneous leishmaniasis (ACL) in the north and northeast regions. Therefore, continuous surveillance of environmental and socioeconomic factors in endemic areas is needed to develop strategic control measures. This study aimed to describe the clinical and epidemiological profiles of patients with ACL.

METHODS:

All patients were from the states of Amazonas and Pernambuco, and examinations were carried out between 2015 and 2018. All patients had a clinical and epidemiological history compatible with ACL after positive diagnostic tests. Information obtained from medical records included gender, employment activity, level of education, age, and number and sites of lesions.

RESULTS:

A total of 213 patients were included, of whom 30.98% were female and 69.02% were male. The main employment activity was agriculture (27.56%). The most common level of education was elementary (62.42%). The average age was approximately 39 years. The majority of the patients presented only with one lesion (54.87%), and legs/feet were the most commonly affected area (48.25%), followed by the arms/hands (44.75%).

CONCLUSIONS:

These data demonstrated that irrespective of the patients’ places of origin, interventions need to be focused on men of economically productive age, in view of the high risk of exposure to the vector in this group. Education activities need to be directed to farmers about the importance of protection against ACL vectors during work. Such information must also be directed to employers as a way of implementing and maintaining appropriate working conditions and stepping up vector control.

Molecular identification of Leishmania in free-ranging black and gold howler monkeys (Alouatta caraya) in northeastern Argentina

Parasitological surveys of non-human primates provides an important opportunity to better understand the epidemiology, transmission dynamics and emergence risk of anthropozoonoses such as leishmaniasis, which affect human populations in several regions accross South America. Our study area, in northeastern Argentina, can be considered a southern marginal region for the presence of leishmaniases and includes the habitat of black and gold howler monkeys, Alouatta caraya. To evaluate if A. caraya serve as potential hosts in the Leishmania cycle, we used molecular methods to examine infection by Leishmania spp. in 109 howler monkeys of different ages captured between July and August 2010. External ear tissue samples were subjected to PCR amplification for the Leishmania ribosomal internal transcribed spacer (ITS-1) and a RFLP assay with the Hae III restriction enzyme, and finally confirmed by sequencing. Nine howler monkeys (8.3%) were infected with Le. braziliensis (2.8%), Le. amazonensis (2.8%) and/or Le. infantum (3.7%). The results also suggest a case of co-infection between Le. braziliensis and Le. amazonensis. Further, we report the first observation of Le. amazonensis in the northeastern region of Argentina. The detection of Leishmania spp. in free-ranging howler monkeys gives rise to questions about the actual prevalence of the parasite in the wild, as well as if the number of infected wild monkeys detected may present a risk of leishmaniasis emergence in surronding human populations. Anyway, the presence of Leishmania spp. in A. caraya suggests the possible importance of these monkeys in the sylvatic and periurban transmission.

B-cell profile, B-cell activating factor concentration and IgG levels in human cutaneous and mucosal leishmaniasis

AIMS

The aim of this study was to evaluate characteristics of B cells in human tegumentary leismaniasis (TL) analysing cutaneous leishmaniasis (CL), most prevalent form and mucosal leishmaniasis (ML), aggressive form characterized by the destruction of the oral-nasal-pharyngeal cavities.

METHODS AND RESULTS

By flow cytometry analysis, we found decreased percentages of non-class-switched memory B cells in TL with the degree of the loss related to clinical severity. Using commercial ELISA, we reported high levels of B-cell activating factor (BAFF) and IgG preferentially in aggressive CL and markedly in ML together with decreased BAFF receptors in the latter. We also found lower levels of BAFF after clinical recovery suggesting a relation between BAFF and disease activity. Mucosal leishmaniasis history of therapeutic failure presented high levels of BAFF accompanied by detectable concentrations of IFN-γ and IL-6 (assayed by commercial ELISA and cytometric bead arrays respectively), cytokines involved in exaggerated inflammatory responses and tissue damage in TL.

CONCLUSION

We demonstrate B-cell disturbances in TL with the degree of the alterations related to clinical severity. We suggest a relation between excess of BAFF and disease activity and point towards a possible implication of BAFF in the inflammatory phenomenon of ML.

Autochthonous Outbreak of Cutaneous Leishmaniasis due to Leishmania infantum in Corrientes Province, Argentina

Endemic cutaneous leishmaniasis (CL) in northern Argentina has traditionally been caused by Leishmania braziliensis. This study aims to describe an outbreak of Leishmania infantum-caused human CL in the Department Capital of Corrientes Province, Argentina. We retrospectively analyzed the reported cases of CL in this area from May 2015 to December 2016. Eighty cases of CL were clinically and analytically diagnosed, and there was one case of visceral leishmaniasis in a boy who also had CL. Patients' median age was 33.6 years (range 1-89 years), and 18.5% were younger than 15 years; the male:female ratio was 3.5:1. Cases lived mostly in the municipality of Corrientes (72.8%), whereas 27.2% resided in Riachuelo. Although 67.9% had a single lesion, 32.1% had several. Molecular analyses showed that L. infantum was the causative species in all cases. Our results show that for the first time, there was an outbreak of CL by L. infantum in an urban area of Argentina.

Spatial dynamics and socioeconomic factors correlated with American cutaneous leishmaniasis in Pernambuco, Brazil from 2008 to 2017

INTRODUCTION:

American cutaneous leishmaniasis (ACL) is a public health problem and has been associated with country’s territory. We aimed to analyze the spatial dynamics and socioeconomic factors correlated to the incidence of ACL in Pernambuco, Brazil from 2008 to 2017.

METHODS:

A cross-sectional, ecological study was conducted in the Brazilian municipalities. Patient data were obtained from the Health Hazard Notification System (SINAN); indicators and incidence for the total period and for quinquennium were obtained. Socioeconomic factors were analyzed to evaluate the association between the incidence of ACL and presence of bathroom and running water, garbage collection availability, inadequate water supply, sanitation, rural population, per capita income, and vulnerability to poverty. Spatial analysis considered the gross incidence; the Bayesian local empirical method and Moran spatial autocorrelation index were applied using Terra View and QGIS.

RESULTS:

The incidence of ACL reduced (0.29/100,000 inhabitants per year). Individuals with ACL were young adults (30.3%), men (60.2%), brown skinned (62.9%), rural residents (70.6%), and less educated (46.7%); had autochthonous transmission (78.8%); developed the cutaneous form (97.2%); had evolution to cure (82.7%); and were diagnosed using the clinical epidemiological criterion (70.5%). ACL occurred in the large part of the state and showed heterogeneous distribution, with persistence of two high priority intervention clusters covering Health Regions I, II, III, IV, and XII.

CONCLUSIONS:

Spatial analysis and epidemiological indicators complement each other. The combination of these methods can improve the understanding on ACL occurrence, which will help subsidize planning and enhance the quality and effectiveness of healthcare interventions.

First Molecular Report of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) guyanensis in Paraguayan Inhabitants Using High-Resolution Melt-PCR

American tegumentary leishmaniasis is an endemic anthropozoonosis undergoing expansion on the American continent. The disease is caused by several Leishmania species and it is manifested as cutaneous and mucocutaneous leishmaniasis. In this study, we evaluate the viability of high-resolution melt polymerase chain reaction (HRM-PCR) analysis to differentiate four closely related Leishmania species as a routine tool for the diagnosis of leishmaniasis. For this purpose, biopsy specimens from cutaneous and mucocutaneous lesions were taken from 132 individuals from endemic and non-endemic areas for leishmaniasis. Each sample was processed for parasitological, histopathological, and molecular analysis. Positive biopsy samples were analyzed by HRM-PCR of a 144-bp heat-shock protein (hsp70) gene fragment, and new cases were confirmed by sequencing. Of the 132 samples analyzed, 36 (27%) were positive for Leishmania spp., of which 86% were from cutaneous lesions and 14% from mucocutaneous lesions. We identified Leishmania (Viannia) braziliensis (84%), Leishmania (Leishmania) infantum (13%), and Leishmania (Leishmania) amazonensis (3%) in cutaneous lesions, and L. (V.) braziliensis (40%), L. (L.) infantum (20%), L. (L.) amazonensis (20%), and Leishmania (Viannia) guyanensis (20%) in mucocutaneous lesions. The main purpose of this research was to report for the first time in Paraguay the presence of L. (L.) amazonensis and L. (V.) guyanensis in patients with cutaneous and mucocutaneous lesions, using the HRM-PCR technique. In addition, we report the presence of additional new cases of L. (L.) infantum in cutaneous lesions.

The Binomial Parasite-Host Immunity in the Healing Process and in Reactivation of Human Tegumentary Leishmaniasis

Leishmaniasis is a vector-borne infectious disease caused by different species of protozoa from the Leishmania genus. Classically, the disease can be classified into two main clinical forms: Visceral (VL) and Tegumentary (TL) leishmaniasis. TL is a skin/mucosal granulomatous disease that manifests mainly as cutaneous localized or disseminated ulcers, papules diffusely distributed, mucosal lesions or atypical lesions. Once the etiology of the infection is confirmed, treatment can take place, and different drugs can be administered. It has already been shown that, even when the scar is clinically evident, inflammation is still present in the native tissue, and the decrease of the inflammatory process occurs slowly during the 1st years after clinical healing. The maintenance of residual parasites in the scar tissue is also well documented. Therefore, it is no longer a surprise that, under some circumstances, therapeutic failure and/or lesion reactivation occurs. All over the years, an impressive amount of data on relapses, treatment resistance and lesion reactivation after healing has been collected, and several factors have been pointed out as having a role in the process. Different factors such as Leishmania species, parasite variability, Leishmania RNA virus 1, parasite load, parasite persistence, age, nutritional status, gender, co-morbidities, co-infection, pregnancy, immunosuppression, lesion duration, number and localization of lesions, drug metabolism, irregular treatment and individual host cellular immune response were described and discussed in the present review. Unfortunately, despite this amount of information, a conclusive understanding remains under construction. In addition, multifactorial influence cannot be discarded. In this context, knowing why leishmaniasis has been difficult to treat and control can help the development of new approaches, such as drugs and immunotherapy in order to improve healing maintenance. In this sense, we would like to highlight some of the findings that may influence the course of Leishmania infection and the therapeutic response, with an emphasis on TL.

Tegumentary leishmaniasis and coinfections other than HIV

BACKGROUND

Tegumentary leishmaniasis (TL) is a disease of skin and/or mucosal tissues caused by Leishmania parasites. TL patients may concurrently carry other pathogens, which may influence the clinical outcome of TL.

METHODOLOGY AND PRINCIPAL FINDINGS

This review focuses on the frequency of TL coinfections in human populations, interactions between Leishmania and other pathogens in animal models and human subjects, and implications of TL coinfections for clinical practice. For the purpose of this review, TL is defined as all forms of cutaneous (localised, disseminated, or diffuse) and mucocutaneous leishmaniasis. Human immunodeficiency virus (HIV) coinfection, superinfection with skin bacteria, and skin manifestations of visceral leishmaniasis are not included. We searched MEDLINE and other databases and included 73 records: 21 experimental studies in animals and 52 studies about human subjects (mainly cross-sectional and case studies). Several reports describe the frequency of Trypanosoma cruzi coinfection in TL patients in Argentina (about 41%) and the frequency of helminthiasis in TL patients in Brazil (15% to 88%). Different hypotheses have been explored about mechanisms of interaction between different microorganisms, but no clear answers emerge. Such interactions may involve innate immunity coupled with regulatory networks that affect quality and quantity of acquired immune responses. Diagnostic problems may occur when concurrent infections cause similar lesions (e.g., TL and leprosy), when different pathogens are present in the same lesions (e.g., Leishmania and Sporothrix schenckii), or when similarities between phylogenetically close pathogens affect accuracy of diagnostic tests (e.g., serology for leishmaniasis and Chagas disease). Some coinfections (e.g., helminthiasis) appear to reduce the effectiveness of antileishmanial treatment, and drug combinations may cause cumulative adverse effects.

CONCLUSIONS AND SIGNIFICANCE

In patients with TL, coinfection is frequent, it can lead to diagnostic errors and delays, and it can influence the effectiveness and safety of treatment. More research is needed to unravel how coinfections interfere with the pathogenesis of TL.

Identification and evaluation of Galleria mellonella peptides with antileishmanial activity

Leishmaniasis is a neglected disease, World Health Organization (WHO) declared it as high priority worldwide. Colombia is one of the 98 countries in which the disease caused more than 17.000 cases per year. There is a need to explore novel therapies to reduce the side effects of the current treatments. For this reason, this study was aimed to evaluate Galleria mellonella hemolymph for potential peptides with anti-parasitic activity. Larvae were challenged with Leishmania (V) panamensis promastigotes and hemolymph was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), reversed-phase chromatography (RP-HPLC), two-dimensional gel electrophoresis and liquid chromatography-mass spectroscopy (LC/MS). The immunological response of Galleria mellonella was followed by SDS-PAGE, immunized hemolymph was fractionated by RP-HPLC where fractions 5 and 11 showed the highest antileishmanial activity. From these fractions 15 spots were isolated by 2D gel electrophoresis and evaluated by LC/MS to identify the peptides present in the spots. After the analysis Moricin-B, Moricin-C4, Cecropin-D and Anionic Peptide 2 were identified due to the immune challenge with Leishmania promastigotes. Anionic peptide 2 and Cecropin-D were synthesized and evaluated for antileishmanial activity. The results showed that Anionic peptide 2 presented more anti-parasitic activity. This study showed for the first time the anti-parasitic potential of peptides derived from hemolymph of Galleria mellonella.

Mucosal leishmaniasis: A Retrospective Study of 327 Cases from an Endemic Area of Leishmania (Viannia) braziliensis

Mucosal leishmaniasis (ML) is observed only in about 3% of patients with American tegumentary leishmaniasis (ATL) but has a high potential for destructive, disfiguring, and disabling sequelae. Prior reports of clinical and epidemiologic features of ML are limited by small numbers of cases. In this study, we evaluated changes in the demographic features and clinical presentation of ML in an endemic area of Leishmania braziliensis transmission over a period of 20 years. The charts of 327 patients with ML diagnosed between 1995 and 2014 were reviewed. The majority of patients (67%) were male. Age ranged from 8 months to 103 years, with a median age of 38.5 years (interquartile range: 22-58 years). The greatest number of patients was between 19 and 39 years (31%). Over the study period, there was an increase in patients with ML more than 60 years of age, an increase in ML with concomitant cutaneous lesions, a decrease in the period of time between the documentation of cutaneous lesions and the diagnosis of mucosal disease, and an increase in the frequency of patients presenting with stage I and V of ML. Moreover, there was a positive correlation between severity of mucosal disease and both age and the period of time between cutaneous lesion and mucosal disease. Response to therapy of ML remained similar over a period of 20 years. Despite the improvement in medical care during the study period, the prevalence of ML did not change and severe disease continues to be a major challenge for the management of these patients.

American cutaneous leishmaniasis in infancy and childhood

Infant and young child skin diseases are among the most common features of morbidity throughout the tropics. Because the skin is directly exposed to the environment, it is considerably affected by climatic and local conditions such as vectors and microorganisms, as in the case of leishmaniasis. In America the observed magnitude of cutaneous leishmaniasis in children has led to the study of increased risk of exposure of this group due to the possibility of peri- and intradomiciliary transmission. The present review pretends to make a concrete approach all through the broad and main figures of this parasitic disease, including the clinical, physiopathological, epidemiological, diagnostic, and therapeutic aspects, in order to be used as a practical source of reference for pediatricians leading with tropical cutaneous pathology in the region.

American tegumentary leishmaniasis: T-cell differentiation profile of cutaneous and mucosal forms-co-infection with Trypanosoma cruzi

American tegumentary leishmaniasis displays two main clinical forms: cutaneous (CL) and mucosal (ML). ML is more resistant to treatment and displays a more severe and longer evolution. Since both forms are caused by the same Leishmania species, the immunological response of the host may be an important factor determining the evolution of the disease. Herein, we analyzed the differentiation and memory profile of peripheral CD4(+) and CD8(+) T lymphocytes of patients with CL and ML and their Leishmania-T. cruzi co-infected counterparts. We measured the expression of CD27, CD28, CD45RO, CD127, PD-1 and CD57, together with interferon-γ and perforin. A highly differentiated phenotype was reflected on both T subsets in ML and preferentially on CD8(+) T cells in CL. A positive trend toward a higher T differentiation profile was found in T. cruzi-infected CL and ML patients as compared with Leishmania single infections. Association between CD8(+) T-cell differentiation and illness duration was found within the first year of infection, with progressive increase of highly differentiated markers over time. Follow-up of patients with good response to therapy showed predominance of early differentiated CD8(+) T cells and decrease of highly differentiated cells, while patients with frequent relapses presented the opposite pattern. CD8(+) T cells showed the most striking changes in their phenotype during leishmaniasis. Patients with long-term infections showed the highest differentiated degree implying a relation between T differentiation and parasite persistence. Distinct patterns of CD8(+) T differentiation during follow-up of different clinical outcomes suggest the usefulness of this analysis in the characterization of Leishmania-infected patients.