Tratamento da Leishmaniose Tegumentar Americana

In vitro leishmanicidal effect of Yangambin and Epi-yangambin lignans isolated from Ocotea fasciculata (Nees) Mez

Introduction

Yangambin and epi-yangambin are the main lignans found in Louro-de-Cheiro [Ocotea fasciculata (Nees) Mez], a tree native to the Atlantic forests of northeastern Brazil whose leaves and bark are widely used in folk medicine. The present study investigated the leishmanicidal and immunomodulatory effects of both lignans in in vitro models of infection by Leishmania amazonensis or Leishmania braziliensis, both etiological agents of Cutaneous Leishmaniasis in Brazil.

Methods

Bone marrow-derived mouse macrophages were infected with L. amazonensis or L. braziliensis and then treated for 48 h at varying concentrations of yangambin or epi-yangambin.

Results

Yangambin and epi-yangambin were found to reduce the intracellular viability of either Leishmania species in a concentration-dependent manner, with respective IC₅₀ values of: 43.9 ± 5 and 22.6 ± 4.9 µM for L. amazonensis, compared to IC₅₀ values of 76 ± 17 and 74.4 ± 9.8 µM for L. braziliensis. In this context, epi-yangambin proved more selective and effective against in vitro infection by L. amazonensis. However, both lignans were found to distinctly modulate the production of inflammatory mediators and other cytokines by macrophages infected by either of the Leishmania species evaluated. While yangambin increased the production of IL-10 by L. braziliensis-infected macrophages, both compounds were observed to lower the production of NO, PGE₂, IL-6 and TNF-α in both Leishmania species.

Discussion

The present results serve to encourage the development of novel studies aimed at screening natural bioactive compounds with the hope of discovering new therapeutic options for the treatment of Cutaneous Leishmaniasis.

Isopropyl Gallate, a Gallic Acid Derivative: In Silico and In Vitro Investigation of Its Effects on Leishmania major

Isopropyl gallate (IPG) is a polyphenol obtained from alterations in the gallic acid molecule via acid catalysis with previously reported leishmanicidal and trypanocidal activities. The present study aims to evaluate in silico binding activity towards some targets for antileishmanial chemotherapy against Leishmania major species, and ADMET parameters for IPG, as well as in vitro antileishmanial and cytotoxic effects. Molecular docking was performed using AutoDockVina and BIOVIA Discovery Studio software, whereas in silico analysis used SwissADME, PreADMET and admetSAR software. In vitro antileishmanial activity on promastigotes and amastigotes of Leishmania major, cytotoxicity and macrophages activation were assessed. IPG exhibited affinity for pteridine reductase (PTR1; -8.2 kcal/mol) and oligopeptidase B (OPB; -8.0 kcal/mol) enzymes. ADMET assays demonstrated good lipophilicity, oral bioavailability, and skin permeability, as well as non-mutagenic, non-carcinogenic properties and low risk of cardiac toxicity for IPG. Moreover, IPG inhibited the in vitro growth of promastigotes (IC₅₀ = 90.813 µM), presented significant activity against amastigotes (IC₅₀ = 13.45 μM), promoted low cytotoxicity in macrophages (CC₅₀ = 1260 μM), and increased phagocytic capacity. These results suggest IPG is more selectively toxic to the parasite than to mammalian cells. IPG demonstrated acceptable in silico pharmacokinetics parameters, and reduced infection and infectivity in parasitized macrophages, possibly involving macrophage activation pathways and inhibition of leishmania enzymes.

Comparison between Colorimetric In Situ Hybridization, Histopathology, and Immunohistochemistry for the Diagnosis of New World Cutaneous Leishmaniasis in Human Skin Samples

New world cutaneous leishmaniasis (NWCL) is an anthropozoonosis caused by different species of the protozoan Leishmania. Colorimetric in situ hybridization (CISH) was shown to satisfactorily detect amastigote forms of Leishmania spp. in animal tissues, yet it was not tested for the diagnosis of human NWCL. The aim of this study was to compare CISH, histopathology (HP), and immunohistochemistry (IHC) techniques to diagnose NWCL in human cutaneous lesions. The sample comprised fifty formalin-fixed, paraffin-embedded skin biopsy specimens from patients with NWCL caused by L. (V.) braziliensis. These specimens were analyzed by CISH, using a generic probe for Leishmania, IHC, and HP to assess the sensitivity of these methods by using a parasitological culture as a standard reference. Additional specimens from three patients diagnosed with cutaneous mycoses were also included to evaluate cross-reactions between CISH and IHC. The sensitivities of IHC, CISH, and HP for detecting amastigotes was 66%, 54%, and 50%, respectively. IHC, unlike CISH, cross-reacted with different species of fungi. Together, these results demonstrate that CISH may be a complementary assay for the detection of amastigote in the laboratorial diagnosis routine of human NWCL caused by L. (V.) braziliensis.

Meglumine antimoniate was associated with a higher cure rate than liposomal amphotericin B in the treatment of American tegumentary leishmaniasis: A retrospective cohort study from a Leishmania braziliensis-endemic area

Background

Pentavalent antimonials (PAs) are the primary therapeutic option for American tegumentary leishmaniasis (ATL). However, the use of these drugs is complicated by adverse events (AEs), resistance and contraindications. Alternative therapies relative effectiveness is not well established.

Objective

This study compared the effectiveness of liposomal amphotericin B (LAB) with intravenous meglumine antimoniate (NMG) in the treatment of ATL. We also analysed and compared associated AEs and treatment interruption rates.

Methods

This was a retrospective cohort study from Brazil. The potential risk factors for the primary outcome were age, sex, total cutaneous lesion area, presence of mucosal lesions, AEs and treatment interruption. The primary outcome was lesion healing within 6 months of treatment. AEs and treatment interruption were also analysed. Multiple analytic strategies were employed to evaluate the reliability of the results.

Results

Before propensity score (PS) matching, patients in the LAB group were older and had a higher frequency of mucosal lesions. The NMG group had a higher cure rate than the LAB group (cure rate 88% versus 55% respectively) in the adjusted analysis (relative risk (RR)=1.55 95% CI: 1.19 - 2.02) and after PS matching (RR=1.63 95% CI: 1.20 - 2.21). NMG group had a higher AE rate (event rate 52% versus 44%) in the adjusted analysis (RR= 1.61, 95% CI: 1.06 - 2.43, p=0.02), but this result was not observed after PS matching (RR= 0.87, 95% CI: 0.49 -1.52, p= 0.61).

Conclusions

We observed that the NMG group had a higher cure rate than the LAB group, with an equivocally higher EV rate in the adjusted analysis.

Bioprospecting marine actinomycetes for antileishmanial drugs: current perspectives and future prospects

Revived analysis interests in natural products in the hope of discovering new and novel antileishmanial drug leads have been driven partially by the increasing incidence of drug resistance. However, the search for novel chemotherapeutics to combat drug resistance had previously concentrated on the terrestrial environment. As a result, the marine environment was often overlooked. For example, actinomycetes are an immensely important group of bacteria for antibiotic production, producing two-thirds of the known antibiotics. However, these bacteria have been isolated primarily from terrestrial sources. Consequently, there have been revived efforts to discover new compounds from uncharted or uncommon environments like the marine ecosystem. Isolation, purification and structure elucidation of target compounds from complex metabolic extract are major challenges in natural products chemistry. As a result, marine-derived natural products from actinomycetes that have antileishmanial bioactivity potentials have been understudied. This review highlights metagenomic and bioassay approaches which could help streamline the drug discovery process thereby greatly reducing time and cost of dereplication to identify suitable antileishmanial drug candidates.

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

Glucantime (Sb^V) 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 Sb^III and Sb^V, serine proteases activity measured with substrate (z-FR-AMC) and specific inhibitors (TLCK, AEBSF and PMSF). In vitro susceptibility of axenic amastigotes to Sb^III 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 Sb^III and serine proteases profiles can aid in the characterization of L. (V.) braziliensis clinical isolates.

A retrospective cohort study of the effectiveness and adverse events of intralesional pentavalent antimonials in the treatment of cutaneous leishmaniasis

Introduction

The standard therapy for American cutaneous leishmaniasis (ACL) is intravenous meglumine antimoniate (IV-MA). However, treatment interruptions due to adverse events (AEs) and non-adherence are frequent. Consequently, intralesional MA (IL-MA) was proposed.

Objective

This study examined the effectiveness of and AEs associated with IL-MA.

Methods

We performed a retrospective cohort study of 240 patients with ACL. We excluded patients with mucous lesions and disseminated leishmaniasis and those who received treatment in the previous 6 months. We considered protocol treatments as the main risk factors. IL-MA was performed using a subcutaneous injection of MA in a volume sufficient to elevate the lesion base (approximately 1 mL/cm² of lesion area) once weekly for 1–8 weeks. IV-MA was performed via intravenous injections of MA at a dosage of 10–20 mg Sb⁵⁺/kg/day for 20 days. The primary outcome was defined as a lesion cure 3 months after treatment, and AEs were secondary outcomes.

Results

Seventy-three patients were included. The IL-MA group consisted of 21 patients, and the IV-MA group consisted of 52 patients. The IL-MA group was older, had more comorbidities and more previous unsuccessful treatment of ACL. The antimonial dose was significantly lower in this group. The cure rate for IL-MA was 66.7%, which was lower than that in the IV-MA group (relative risk (RR) = 0.68, 95% CI: 0.50–0.92, p < 0.001), while the rate of AEs was similar. Female sex (RR = 1.16, 95% CI: 1.02–1.33), lesion diameter ≤1 cm (RR = 1.25, 95% CI: 1.00–1.56) and treatment with IV-MA (RR = 1.43, 95% CI: 1.06–1.93) were independently associated with achieving a cure. Comorbidities (RR = 1.7, 95% CI: 1.06–2.98) were independently associated with AEs.

Conclusions

Patients of IL-MA group were older, had more comorbidities and more previous unsuccessful treatment of ACL. Nevertheless, IL-MA had a cure rate of 66.7%, and it was useful in this context. A prospective randomized trial is recommended.

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Intralesional antimonials (IL-MA) had a 66.7% lower cure compared to systemic.

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IL-MA group was older, had more comorbidities and unsuccessful previous treatment.

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IL-MA was useful in this group, where worse clinical responses are expected.

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Lesions larger than 3 cm did not have more chance of failure with IL-MA.

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There was no mucous recurrence after IL-MA in an area of New World Leishmaniasis.

Evaluation of in vitro and in vivo Efficacy of a Novel Amphotericin B-Loaded Nanostructured Lipid Carrier in the Treatment of Leishmania braziliensis Infection

Background

Leishmaniasis is a neglected disease, and the current therapeutic arsenal for its treatment is seriously limited by high cost and toxicity. Nanostructured lipid carriers (NLCs) represent a promising approach due to high drug loading capacity, controlled drug release profiles and superior stability. Here, we explore the efficacy of a unique pH-sensitive amphotericin B-loaded NLC (AmB-NLC) in Leishmania braziliensis infection in vitro and in vivo.

Methods and Results

AmB-NLC was assessed by dynamic light scattering and atomic force microscopy assays. The carrier showed a spherical shape with a nanometric size of 242.0 ± 18.3 nm. Zeta potential was suggestive of high carrier stability (−42.5 ± 1.5 mV), and the NLC showed ~99% drug encapsulation efficiency (EE%). In biological assays, AmB-NLC presented a similar IC₅₀ as free AmB and conventional AmB deoxycholate (AmB-D) (11.7 ± 1.73; 5.3 ± 0.55 and 13 ± 0.57 ng/mL, respectively), while also presenting higher selectivity index and lower toxicity to host cells, with no observed production of nitric oxide or TNF-α by in vitro assay. Confocal microscopy revealed the rapid uptake of AmB-NLC by infected macrophages after 1h, which, in association with more rapid disruption of AmB-NLC at acidic pH levels, may directly affect intracellular parasites. Leishmanicidal effects were evaluated in vivo in BALB/c mice infected in the ear dermis with L. braziliensis and treated with a pentavalent antimonial (Sb⁵⁺), liposomal AmB (AmB-L) or AmB-NLC. After 6 weeks of infection, AmB-NLC treatment resulted in smaller ear lesion size in all treated mice, indicating the efficacy of the novel formulation.

Conclusion

Here, we preliminarily demonstrate the effectiveness of an innovative and cost-effective AmB-NLC formulation in promoting the killing of intracellular L. braziliensis. This novel carrier system could be a promising alternative for the future treatment of cutaneous leishmaniasis.

Drug-containing hydrophobic dressings as a topical experimental therapy for cutaneous leishmaniasis

Cutaneous leishmaniasis (CL), a clinical condition caused mainly by Leishmania amazonensis in Brazil, is characterized by topical, painless ulcers. The current treatment, based on intravenous administration of pentavalent antimonials, presents low adherence by patients and may cause serious adverse effects, leading to the need for searching new therapeutic options. Thus, this study aimed at evaluating a topical administration of "intelligent dressings" as an alternative treatment for CL. BALB/c mice were infected with L. amazonensis promastigotes. Afterward, lesions were treated with hydrophobic dressings incorporated with clinically used drugs. After lesion development, the following analyses were carried out: measurement of lesion diameters, biochemical analyses of serum, evaluation of the recovery of amastigote forms and histological analyses. No significant clinical changes in serum parameters were observed. The group that was treated with dressings impregnated with Glucantime^® displayed the lowest number of amastigotes recovered from tissues (parasite load). Conventional treatment with Glucantime^® (i.p.) was also able to reduce parasite load. After 6 weeks from the measurement of the lesions mice treated with dressings impregnated with Pentamidine displayed the smallest values. Representative histological aspects of the lesions showed the absence or few amastigotes inside the macrophages when mice were treated with dressings impregnated with Glucantime^® and Pentamidine, respectively. The findings presented here indicate that the topical treatments may constitute an alternative treatment option for CL.

Combined Strategies to Improve the Expression of Recombinant Sterol C24-Methyltransferase from Leishmania braziliensis in E. coli

Among the neglected tropical diseases, leishmaniasis stands out for its worldwide distribution and diversity of symptoms. Cutaneous leishmaniasis (CL), for instance, is endemic in 18 countries, but the available drugs to fight it have high toxicity and low patient adherence. In order to overcome this, dilemma drugs that target enzymes which are absent in the human host, such as Leishmania braziliensis sterol C24-methyltransferase (SMT-C24, EC 2.1.1.41), are needed. However, medicinal chemistry efforts toward this goal have been hampered by the low yield of soluble recombinant SMT-C24 afforded by currently available expression systems. Herein, we show that a combination of molecular biology and chromatographic strategies may increase the yield of LbSMT-C24 in up to fivefold. These results lay the ground for future investigation of this enzyme as a drug target.

Meglumine Antimoniate (Glucantime) Causes Oxidative Stress-Derived DNA Damage in BALB/c Mice Infected by Leishmania (Leishmania) infantum

Leishmaniasis is a neglected tropical disease caused by >20 species of the protozoan parasite Leishmania Meglumine antimoniate (Glucantime) is the first-choice drug recommended by the World Health Organization for the treatment of all types of leishmaniasis. However, the mechanisms of action and toxicity of pentavalent antimonials, including genotoxic effects, remain unclear. Therefore, the mechanism by which meglumine antimoniate causes DNA damage was investigated for BALB/c mice infected by Leishmania (Leishmania) infantum and treated with meglumine antimoniate (20 mg/kg for 20 days). DNA damage was analyzed by a comet assay using mouse leukocytes. Furthermore, comet assays were followed by treatment with formamidopyrimidine-DNA glycosylase and endonuclease III, which remove oxidized DNA bases. In addition, the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the animals' sera were assessed. To investigate mutagenicity, we carried out a micronucleus test. Our data demonstrate that meglumine antimoniate, as well as L. infantum infection, induces DNA damage in mammalian cells by the oxidation of nitrogenous bases. Additionally, the antileishmanial increased the frequency of micronucleated cells, confirming its mutagenic potential. According to our data, both meglumine antimoniate treatment and L. infantum infection promote oxidative stress-derived DNA damage, which promotes overactivation of the SOD-CAT axis, whereas the SOD-GPx axis is inhibited as a probable consequence of glutathione (GSH) depletion. Finally, our data enable us to suggest that a meglumine antimoniate regimen, as recommended by the World Health Organization, would compromise GPx activity, leading to the saturation of antioxidant defense systems that use thiol groups, and might be harmful to patients under treatment.

Leishmanicidal, cytotoxicity and wound healing potential of Arrabidaea chica Verlot

BACKGROUND

Leishmaniasis includes a wide complex of diseases that affect humans and other mammals, and can range from a mild cutaneous form to a severe visceral type. The safety of the standard treatment using pentavalent antimony is a concern due to its toxic effects. The search for alternative, effective and less toxic treatments has led to the testing of natural products. The present study aimed to evaluate the cytotoxic, leishmanicidal and healing potential of Arrabidaea chica.

METHODS

The crude ethanolic extract, as well as the chloroform, methanol and ethyl acetate fractions of A. chica were prepared and phytochemical analysis was performed. Cytotoxic evaluation was carried out through MTT colorimetric assay, and the 50% cellular cytotoxicity was determined. After that, the effect of the extract and fractions against Leishmania amazonensis promastigotes, at intervals of 24, 48 and 72 h, was analyzed, and 50% inhibitory concentration was determined. The healing effect of the plant was also tested in surgical lesions in Swiss mice skin.

RESULTS

Phytochemical screening showed that the crude extracts contained flavonoids, tannins, anthocyanidins and chalcones. The leishmanicidal potential of A. chica produced satisfactory results in concentrations of between 60 and 155.9 μg/mL. Cytotoxic assay revealed a 50% reduction in viable cells at a concentration of 189.9 μg/mL. The healing results indicated that the treated group exhibited more pronounced signs of lesion resolution in the early period, but this pattern did not persist throughout the treatment.

CONCLUSIONS

The results of the present study demonstrate that A. chica has cytotoxic and leishmanicidal potential but its healing effect must be better studied.

Development, characterization, and in vitro biological performance of fluconazole-loaded microemulsions for the topical treatment of cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) is a resistant form of leishmaniasis that is caused by a parasite belonging to the genus Leishmania. FLU-loaded microemulsions (MEs) were developed by phase diagram for topical administration of fluconazole (FLU) as prominent alternative to combat CL. Three MEs called F1, F2, and F3 (F1—60% 50 M phosphate buffer at pH 7.4 (PB) as aqueous phase, 10% cholesterol (CHO) as oil phase, and 30% soy phosphatidylcholine/oil polyoxyl-60 hydrogenated castor oil/sodium oleate (3/8/6) (S) as surfactant; F2—50% PB, 10% CHO, and 40% S; F3—40% PB, 10% CHO, and 50 % S) were characterized by droplet size analysis, zeta potential analysis, X-ray diffraction, continuous flow, texture profile analysis, and in vitro bioadhesion. MEs presented pseudoplastic flow and thixotropy was dependent on surfactant concentration. Droplet size was not affected by FLU. FLU-loaded MEs improved the FLU safety profile that was evaluated using red cell haemolysis and in vitro cytotoxicity assays with J-774 mouse macrophages. FLU-unloaded MEs did not exhibit leishmanicidal activity that was performed using MTT colourimetric assays; however, FLU-loaded MEs exhibited activity. Therefore, these MEs have potential to modulate FLU action, being a promising platform for drug delivery systems to treat CL.

Risk factors for adverse prognosis and death in American visceral leishmaniasis: a meta-analysis

BACKGROUND

In the current context of high fatality rates associated with American visceral leishmaniasis (VL), the appropriate use of prognostic factors to identify patients at higher risk of unfavorable outcomes represents a potential tool for clinical practice. This systematic review brings together information reported in studies conducted in Latin America, on the potential predictors of adverse prognosis (continued evolution of the initial clinical conditions of the patient despite the implementation of treatment, independent of the occurrence of death) and death from VL. The limitations of the existing knowledge, the advances achieved and the approaches to be used in future research are presented.

METHODS/PRINCIPAL FINDINGS

The full texts of 14 studies conforming to the inclusion criteria were analyzed and their methodological quality examined by means of a tool developed in the light of current research tools. Information regarding prognostic variables was synthesized using meta-analysis. Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses. The strongest predictors identified in this review were jaundice, thrombocytopenia, hemorrhage, HIV coinfection, diarrhea, age <5 and age >40-50 years, severe neutropenia, dyspnoea and bacterial infections. Edema and low hemoglobin concentration were also associated with unfavorable outcomes. The main limitation identified was the absence of validation procedures for the few prognostic models developed so far.

CONCLUSIONS/SIGNIFICANCE

Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes. The development of externally validated prognostic models must be prioritized in future investigations.

Liposomal-lupane system as alternative chemotherapy against cutaneous leishmaniasis: macrophage as target cell

Leishmania amazonensis causes human diseases that range from self-healing to diffusion cutaneous lesions. The chemotherapy of leishmaniasis requires long-term treatment and has been based on the use of pentavalent antimonials. Liposomes have been used as antileishmanial drug carries and have adjuvant activity in vaccines against several microorganisms, representing an important option to the development of new therapeutics for the disease. In this study, we developed a liposomal formulation containing lupane [3β,6β,16β-trihydroxylup-20(29)-ene], isolated from fruits of Combretum leprosum with pharmacological properties as antinociceptive, anti-inflammatory, antiulcerogenic and antileishmanial activities. The aim of the present study was to evaluate the efficacy of liposomal-lupane in L. amazonensis-infection model. Liposomes were prepared by the extrusion method with DPPC, DPPS and cholesterol at 5:1:4 weight ratio. The lupane (2 mg/mL) was added to the lipid mixture, solubilized in chloroform and dried under nitrogen flow. The activity of liposomal-lupane was conducted in vitro with mouse peritoneal infected macrophages. Furthermore, mice were infected in the right hind footpad with 10(5) stationary growth phase of L. amazonensis promastigotes. After 6 weeks, animals were treated with liposomal-lupane for 15 days by intraperitoneal injection. The evolution of disease was monitored weekly by measuring footpad thickness with a caliper. Three days after the treatment, peritoneal macrophages were collected, plated and production of the cytokines IL-10 and IL-12 was evaluated in supernatants of the cultures after 24 h. The results indicate that the liposomal system containing lupane achieved here is a promising tool to confer antileishmanial activity to infected macrophages.

Brazilian propolis antileishmanial and immunomodulatory effects

The antileishmanial and immunomodulatory effects of propolis collected in Botucatu, São Paulo State, Brazil, were evaluated in Leishmania (Viannia) braziliensis experimental infection. The antileishmanial effect of propolis on promastigote forms was verified by reducing growth and by promoting morphologic alterations observed by scanning electron microscopy. In in vitro immunomodulatory assays, macrophages were pretreated with propolis and then infected with L. (V.) braziliensis. In vivo, supernatants from liver cells and peritoneal exudate of BALB/c mice pretreated with propolis and infected with Leishmania (10⁷/mL promastigotes) were collected, and TNF-α and IL-12 were measured by ELISA. Macrophages incubated with propolis showed a significant increase in interiorization and further killing of parasites. An increased TNF-α production was seen in mice pretreated with propolis, whereas IL-12 was downregulated during the infection. In conclusion, Brazilian propolis showed a direct action on the parasite and displayed immunomodulatory effects on murine macrophages, even though the parasite has been reported to affect the activation pathways of the cell. The observed effects could be associated with the presence of phenolic compounds (flavonoids, aromatic acids, and benzopyranes), di- and triterpenes, and essential oils found in our propolis sample.

Periungual leishmaniasis

The vast majority of cases of cutaneous leishmaniasis are represented by limb injuries. A female patient, white, presented an ulcer with infiltrated borders located on the fourth finger of the left hand following occupational exposure in an area of native forest. Diagnosis of cutaneous leishmaniasis caused by Leishmania of the subgenus Viannia was confirmed. The patient failed to respond to treatment with antimony, but achieved clinical cure after this was associated with pentoxifylline. The case highlights the rarity of the periungual location of the leishmanial lesion and the difficulties encountered in therapy.

Dermatological diseases of compulsory notification in Brazil

The development of a Brazilian National Surveillance System in 1975 led to a compulsory reporting of selected infectious diseases aiming to reduce the burden of these events in the country. However, shifts in the epidemiology of these diseases associated with modern life style, demand constant revision of surveillance activities. In this manuscript we present the epidemiology, trends and differential diagnosis of the following compulsory notifiable diseases in Brazil: Aids, dengue fever, hanseniasis, American tegumentary leishmaniasis, measles, rubella and congenital rubella syndrome and syphilis. Additionally, the current challenges for control and prevention of each disease are presented.

Combining diagnostic procedures for the management of leishmaniasis in areas with high prevalence of Leishmania guyanensis

BACKGROUND: The Amazon region corresponds to approximately 40% of the cases of leishmaniasis in Brazil. We report a prospective study with 180 patients conducted in a health care unit that diagnoses 10% of the cases of leishmaniasis in the Brazilian Amazon. The study addresses how a combination of procedures improves diagnosis in areas with high prevalence of Leishmania guyanensis. OBJECTIVES: to evaluate diagnostic methods in areas with high prevalence of Leishmania guyanensis. METHODS: All subjects were amastigote-positive by direct microscopic examination of lesion scarifications. We conducted skin biopsy and histopathology, polymerase chain reaction and parasite cultivation. RESULTS: Polymerase chain reaction detected almost ninety percent of infections when two amplification protocols were used (mini-exon and HSP-70). HSP-70 specific polymerase chain reaction matched the sensitivity of parasite cultivation plus histopathology. CONCLUSION: The best combination was polymerase chain reaction plus histopathology, which increased diagnostic sensitivity to 94%. Species discrimination by polymerase chain reaction disclosed prevalence of human infections with Leishmania guyanensis of 94% and with Leishmania braziliensis of 6% for this region

Estudo clínico randomizado comparando antimoniato de meglumina, pentamidina e anfotericina B para o tratamento da leishmaniose cutânea ocasionada por Leishmania guyanensis

FUNDAMENTOS: O tratamento da leishmaniose tegumentar americana (LTA) ainda constitui desafio, pois a maioria dos medicamentos é injetável e têm-se poucos ensaios clínicos randomizados comparando a eficácia das drogas. Além disso, é provável que as espécies de Leishmania tenham influência nas respostas terapêuticas. OBJETIVOS: Avaliar e comparar a eficácia e a segurança dos esquemas de tratamento na LTA, ocasionada por Leishmania (Viannia) guyanensis. MÉTODOS: 185 pacientes foram selecionados, conforme critérios de elegibilidade, e distribuídos, aleatoriamente, em 3 grupos - 2 com 74 enfermos e outro com 37 - que receberam, respectivamente, antimoniato de meglumina, isotionato de pentamidina e anfotericina B em doses, períodos e vias de administração padronizados. Os enfermos foram reexaminados um, dois e seis meses após o final dos tratamentos. RESULTADOS: Não houve diferença entre os grupos terapêuticos em relação ao sexo, idade, número ou local das lesões. A análise por intenção de tratar (ITT) mostrou eficácias de 58,1% para a pentamidina e 55,5% para o antimoniato (p=0,857). O grupo da anfotericina B foi analisado separadamente, pois 28 (75,7%) pacientes negaram-se a continuar no estudo após a randomização. Eventos adversos leves ou moderados foram relatados por 74 (40%) pacientes, principalmente artralgia (20,3%), para o grupo do antimoniato, e dor (35,1%) ou enduração (10,8%) no local das injeções para a pentamidina. CONCLUSÕES: A pentamidina tem eficácia similar ao antimonial pentavalente para o tratamento da LTA ocasionada por L. guyanensis. Face aos baixos resultados de eficácia apresentados por ambas as drogas, necessita-se, com urgência, investigar novas opções terapêuticas para esta enfermidade.

Avanços no tratamento da leishmaniose tegumentar do novo mundo nos últimos dez anos: uma revisão sistemática da literatura

INTRODUÇÃO: O arsenal terapêutico contra a leishmaniose tegumentar é muito restrito. Os antimoniais pentavalentes permanecem como as drogas de escolha para seu tratamento há mais de 50 anos. Apesar da sua eficácia, necessita de injeções diárias, apresenta muitos efeitos colaterais e tempo de cura prolongado. OBJETIVO: Realizar uma revisão sistemática da literatura sobre os avanços no tratamento da leishmaniose tegumentar do novo mundo nos últimos dez anos. METODOLOGIA: Realizou-se em junho de 2009 uma busca eletrônica nas bases de dados Pubmed, LILACS e na biblioteca eletrônica Scielo. As palavras de busca em inglês foram: "cutaneous", "leishmaniasis" e "treatment". Foram incluÃdos apenas ensaios clÃnicos randomizados, duplo-cegos, placebo controlados. Utilizou-se a escala de Jadad para avaliar a qualidade dos estudos selecionados. RESULTADOS: Segundo os critérios de inclusão e exclusão, apenas 8 artigos foram selecionados. As drogas avaliadas nos estudos selecionados foram Glucantime®, miltefosine, imunoterapia, imiquimod, rhGM-CSF, pentoxifilina e paramomicina. CONCLUSÃO: Apesar de a leishmaniose tegumentar ser um importante problema de saúde pública, os dados publicados sobre o uso de novas drogas para o tratamento da leishmaniose tegumentar em nosso meio ainda são bastante limitados

Systematic review of the adverse effects of cutaneous leishmaniasis treatment in the New World

Pentavalent antimonials are first-line drugs for the treatment of the cutaneous form of American tegumentary leishmaniasis. Second-line drugs include amphotericin B and pentamidine. Although these drugs have been used for decades, there are no systematic reviews about their safety. The objective of this review was to identify and classify the main adverse effects associated with these drugs and to estimate the frequency of these effects, whenever possible. Intervention studies, case series and case reports containing information regarding clinical, laboratory or electrocardiographic adverse effects of drugs used for the treatment of cutaneous leishmaniasis were systematically retrieved from 10 databases searched between August 13, 2008 and March 31, 2009. The 65 studies included in this review had treated a total of 4359 patients from 12 countries infected with eight different Leishmania species. Despite the small number of drugs used in these studies, a wide variability in the therapeutic regimens was observed. As a consequence, the adverse effects of pentavalent antimonials and pentamidine needed to be classified jointly according to system, irrespective of formulation, daily dose, duration of treatment, and route of administration. The frequencies of adverse effects were calculated based on the data of 32 articles involving 1866 patients. The most frequently reported clinical adverse effects of pentavalent antimonials and pentamidine were musculoskeletal pain, gastrointestinal disturbances, and mild to moderate headache. Electrocardiographic QTc interval prolongation and a mild to moderate increase in liver and pancreatic enzymes were additional adverse effects of pentavalent antimonials. Patients treated with liposomal amphotericin B had mild dyspnea and erythema. The adverse effects associated with miltefosine were vomiting, nausea, kinetosis, headache, diarrhea, and a mild to moderate increase in aminotransferases and creatinine. Although closer surveillance is needed for the treatment of cutaneous leishmaniasis, antileishmanial drugs are basically safe and severe side effects requiring the discontinuation of treatment are relatively uncommon.