Cutaneous and mucocutaneous leishmaniasis: Differential diagnosis, diagnosis, histopathology, and management

TGF-beta plays dual roles in immunity and pathogenesis in leishmaniasis

Transforming growth factor-beta (TGF-β), displaying a dual role in immunosuppression and pathogenesis, has emerged as a key regulator of anti-leishmanial immune responses. In Leishmania infections, TGF-β drives immune deviation by enhancing regulatory T-cell (T-reg) differentiation and inhibiting macrophage activation, suppressing critical antiparasitic responses. This cytokine simultaneously promotes fibroblast proliferation, extracellular matrix production, and fibrosis in infected tissues, which aids in wound healing but impedes immune cell infiltration, particularly in visceral leishmaniasis, where splenic disorganization and compromised immune access are notable. In conjunction with IL-6, TGF-β modulates pathogenic Th17 responses which intensify inflammatory damage and disrupt tissue architecture. While TGF-β's immunosuppressive actions enable parasite persistence, its role in maintaining tissue integrity introduces therapeutic potential. Targeted modulation of TGF-β signaling, through selective inhibitors of TGF-β receptors or signaling intermediates, has the potential to enhance parasite clearance while minimizing immunopathology. Experimental studies suggest that phase-specific intervention strategies may allow for controlled immunostimulation or fibrosis reduction, enhancing host resistance without incurring inflammatory injury. This review discusses the intricate role of TGF-β in orchestrating immune deviation, fibrosis, and pathogenesis in leishmaniasis, proposing novel therapeutic avenues for selective modulation of TGF-β pathways to restore host immunity.

Leishmaniasis in Patients With Inflammatory Bowel Disease: A National Multicenter Study of GETECCU

BACKGROUND

Leishmaniasis (LI) is a vector-borne illness caused by a protozoan of the genus Leishmania. Data on the features of LI in patients with inflammatory bowel disease (IBD) are scarce.

AIM

To describe the characteristics of patients with IBD who present with leishmaniasis, infection outcomes and the risk factors associated with developing visceral leishmaniasis (VL).

METHODS

An observational retrospective study performed in 26 hospitals in Spain, including all adult patients with IBD who developed Leishmaniasis from 2012 to 2022.

RESULTS

A total of 73 patients were included [mean age 48 years; 65% male; 68% Crohn's disease]. Sixty patients (82.2%) presented localized cutaneous Leishmaniasis (CL), 2 (2.7%) diffuse CL, 3 (4.1%) mucocutaneous Leishmaniasis (MCL) and 8 (11%) VL. All patients were under biologicals (69 [94.5%]) or immunosuppressants (IMM) (4 [5.5%]) at Leishmaniasis diagnosis. AntiTNF was used in 97%, while 2 patients (3%) were receiving ustekinumab. Leishmaniasis resolution was achieved by 48% and 96% of the patients after 1 and 12 months, respectively. Biological withdrawal after Leishmaniasis diagnosis was not statistically related to increased rates of infection resolution among patients with localized CL. Age was the only risk factor associated with VL (OR 1.2, 95%CI 1.04-1.39; p = 0.012).

CONCLUSIONS

Leishmaniasis in patients with IBD doesn't seem to follow a complicated clinical course, even in those with localized CL who do not discontinue biological therapy after infection diagnosis. Age might be a risk factor for developing VL. This infection should be considered for immunosuppressed patients with IBD and suggestive symptoms dwelling or travelling to endemic areas.

Exploring the Potential of Malvidin and Echiodinin as Probable Antileishmanial Agents Through In Silico Analysis and In Vitro Efficacy

Leishmaniasis, a neglected tropical disease caused by Leishmania species, presents serious public health challenges due to limited treatment options, toxicity, high costs, and drug resistance. In this study, the in vitro potential of malvidin and echioidinin is examined as antileishmanial agents against L. amazonensis, L. braziliensis, and L. infantum, comparing their effects to amphotericin B (AmpB), a standard drug. Malvidin demonstrated greater potency than echioidinin across all parasite stages and species. Against L. amazonensis, malvidin's IC50 values were 197.71 ± 17.20 µM (stationary amastigotes) and 258.07 ± 17 µM (axenic amastigotes), compared to echioidinin's 272.99 ± 29.90 μM and 335.96 ± 19.35 μM. AmpB was more potent, with IC50 values of 0.06 ± 0.01 µM and 0.10 ± 0.03 µM. Malvidin exhibited lower cytotoxicity (CC50: 2920.31 ± 80.29 µM) than AmpB (1.06 ± 0.12 µM) and a favorable selectivity index. It reduced infection rates by 35.75% in L. amazonensis-infected macrophages. The in silico analysis revealed strong binding between malvidin and Leishmania arginase, with the residues HIS139 and PRO258 playing key roles. Gene expression analysis indicated malvidin's modulation of oxidative stress and DNA repair pathways, involving genes like GLO1 and APEX1. These findings suggest malvidin's potential as a safe, natural antileishmanial compound, warranting further in vivo studies to confirm its therapeutic efficacy and pharmacokinetics in animal models.

Exploring Bioinformatics Solutions for Improved Leishmaniasis Diagnostic Tools: A Review

Significant populations in tropical and sub-tropical locations all over the world are severely impacted by a group of neglected tropical diseases called leishmaniases. This disease is caused by roughly 20 species of the protozoan parasite from the Leishmania genus. Disease prevention strategies that include early detection, vector control, treatment of affected individuals, and vaccination are all essential. The diagnosis is critical for selecting methods of therapy, preventing transmission of the disease, and minimizing symptoms so that the affected individual can have a better quality of life. Nevertheless, the diagnostic methods do eventually have limitations, and there is no established gold standard. Some disadvantages include the existence of cross-reactions with other species, and limited sensitivity and specificity, which are mostly determined by the type of antigen used to perform the tests. A viable alternative for a more precise diagnosis is the application of recombinant antigens, which have been generated using bioinformatics approaches and have shown increased diagnostic accuracy. This approach proves valuable as it spans from epitope selection to predicting the interactions within the antibody-antigen complex through docking analysis. As a result, identifying potential new antigens using bioinformatics resources becomes an effective technique since it may result in an earlier and more accurate diagnosis. Consequently, the primary aim of this review is to conduct a comprehensive overview of the most significant in silico tools developed over time, with a focus on evaluating their efficacy and exploring their potential applications in optimizing the selection of highly specific molecules for a more effective diagnosis of leishmaniasis.

Rethinking Histology Slide Digitization Workflows for Low-Resource Settings

Histology slide digitization is becoming essential for telepathology (remote consultation), knowledge sharing (education), and using the state-of-the-art artificial intelligence algorithms (augmented/automated end-to-end clinical workflows). However, the cumulative costs of digital multi-slide high-speed brightfield scanners, cloud/on-premises storage, and personnel (IT and technicians) make the current slide digitization workflows out-of-reach for limited-resource settings, further widening the health equity gap; even single-slide manual scanning commercial solutions are costly due to hardware requirements (high-resolution cameras, high-spec PC/workstation, and support for only high-end microscopes). In this work, we present a new cloud slide digitization workflow for creating scanner-quality whole-slide images (WSIs) from uploaded low-quality videos, acquired from cheap and inexpensive microscopes with built-in cameras. Specifically, we present a pipeline to create stitched WSIs while automatically deblurring out-of-focus regions, upsampling input 10X images to 40X resolution, and reducing brightness/contrast and light-source illumination variations. We demonstrate the WSI creation efficacy from our workflow on World Health Organization-declared neglected tropical disease, Cutaneous Leishmaniasis (prevalent only in the poorest regions of the world and only diagnosed by sub-specialist dermatopathologists, rare in poor countries), as well as other common pathologies on core biopsies of breast, liver, duodenum, stomach and lymph node. The code and pretrained models will be accessible via our GitHub (https://github.com/nadeemlab/DeepLIIF), and the cloud platform will be available at https://deepliif.org for uploading microscope videos and downloading/viewing WSIs with shareable links (no sign-in required) for telepathology and knowledge sharing.

Diagnostic challenges in cutaneous leishmaniasis due to atypical Leishmania infantum: pathologists' insights from re-emergence zones

Background

Leishmaniasis, a parasitic infection affecting both humans and animals, is increasingly spreading across Mediterranean and European regions, largely driven by human migration and environmental changes. In countries like Türkiye and across Europe, which have seen large influxes of migrants, the incidence of cutaneous leishmaniasis (CL) is rising, with cases now appearing in cities where the disease was previously undocumented. In these previously non-endemic areas, physicians unfamiliar with the characteristic lesions may misdiagnose CL, particularly in cases with only cutaneous manifestations. This study aims to evaluate the impact of re-emerging CL on the routine diagnostic practices of pathologists in Türkiye, by retrospectively reviewing cases.

Methods

We conducted a retrospective analysis of CL cases diagnosed between 2013 and 2022 at a single pathology center in Türkiye, covering multiple provinces. Twelve cases of CL were identified and analyzed based on clinical presentation, pre-diagnosis, histopathological findings, and molecular diagnostics. DNA extraction and PCR were performed on paraffin-embedded tissue samples to identify the Leishmania species involved.

Results

Out of the twelve CL cases reviewed, seven exhibited morphological findings strongly suggestive of CL (MFSS of CL), warranting further microbiological evaluation. All patients presented with non-healing skin lesions characterized by central ulceration, crater-like formations, or papulonodular lesions. Notably, CL was included in the clinical pre-diagnosis in only 58.3% of cases, while it was not considered in the remaining 41.7% of cases. Clinicians initially pre-diagnosed skin tumors in six cases (50%), four of which led to wide surgical excision. Histopathological examination in all cases revealed chronic or mixed (acute/chronic) inflammation, predominantly rich in histiocytes. To further investigate the role of Leishmania species in the pre-diagnosis, DNA extraction and PCR were performed on paraffin-embedded tissue samples, identifying L. infantum as the causative agent in 10 cases and L. major in two cases. Notably, L. infantum was the causative agent in all five cases initially misdiagnosed as skin tumors, which were also associated with a granulomatous type of chronic inflammation.

Honey therapies for dermatological disorders: more than just a sweet elixir

Honey possesses antibacterial, anti-inflammatory, and healing properties that benefit wound healing and tissue regeneration. For centuries, honey has been utilized in traditional medicine as a binder or vehicle for creams and lotions and also for therapeutic purposes. The overuse of antibiotics and antimicrobial agents leading to drug resistance has emphasized the resurgence of honey's application in wound care. For many dermatological disorders, there is an interest in developing therapeutics with fewer side effects than traditional therapies and enhanced wound healing abilities to expedite tissue regeneration. This paper reviews the properties and components of honey that contribute to its wound-healing-based applications, the types of honey employed in medicine, and its dermatological applications. Based on the evidence from case reports, clinical trials, and in vitro studies, honey has been characterized as a safe, cost-effective, and readily available treatment option for many skin conditions, including microbial infections, atopic dermatitis, psoriasis, necrotizing fasciitis, ulcers, as well as thermal and other types of wounds.

Clinical and laboratory characterization of cutaneous leishmaniasis in Chinese migrant workers returned from Iraq

BACKGROUND

Imported cutaneous leishmaniasis (CL) is a growing problem with increasing global travel to endemic areas. Returned travelers with CL are easy to be misdiagnosed and mistreated due to the lack of awareness for the disease to the physicians in non-endemic region that may lead to unfavorable outcome. Our study intends to summarize the characteristics of Leishmania infection imported from Iraq, so as to help Chinese physicians diagnose and treat the disease. All CL patients were treated with intralesional injection of antimony.

METHODS

The definitive diagnosis of CL is based on the parasite identification by microscopic examination directly on lesion smear or parasite culture, PCR amplification of Leishmania-specific internal transcribed spacer 1 (ITS-1). The phylogenetic analysis, the immunopathological examination and the cytokine detection were proceeded after the diagnosis.

RESULTS

We have identified 25 CL cases in migrant Chinese workers returned from Iraq for the first time with L. major as the major species of infected Leishmania parasite. Clinical features of the Iraq-imported CL include the history of skin exposure to sandflies bite and the lesions mostly on the exposed limbs. More ulcerative wet lesion was observed than nodular dry lesion. PCR is not only used to detect Leishmania parasite with high sensitivity, but also to identify the species of infected parasite through sequencing the amplified Leishmania-specific ITS-1 gene. The phylogenetic analysis based on the amplified ITS-1 sequences revealed that the infected Leishmania was closed related to the species and strains endemic in Iraq. The immunopathological examination revealed the T-cell filtrated cellular immune response with less B cells and NK cells involved. The cytokine profile measured in the skin lesion also confirmed the Th1 cellular response with higher expression levels of IFN-γ, IL-6 and IL-8. The skin lesions in CL patients were healed after being treated locally with antimony.

CONCLUSIONS

The clinical and parasitological features of these Chinese CL cases imported from Iraq provide useful information for the diagnosis and treatment of CL that is not commonly seen in Chinese local population.

In Situ versus Systemic Immune Response in the Pathogenesis of Cutaneous Leishmaniasis

The role of the immune response in the pathogenesis of cutaneous leishmaniasis (CL) due to Leishmania (Viannia) braziliensis is predominantly carried out via blood cells. Here, we evaluate whether cytokine production by peripheral blood mononuclear cells (PBMCs) reflects what has been documented at the lesion site. The participants included 22 CL patients diagnosed with a positive PCR. PBMCs were stimulated for 72 h with a soluble leishmania antigen (SLA). Biopsies obtained from the edge of the ulcers were incubated for the same period. Cytokines in supernatants were assessed via ELISA. TNF, IL-1β, IL-6, IL-17, and granzyme B (GzmB) were higher in the supernatants of biopsies than in PBMCs, but IFN-γ was higher in the supernatants of PBMCs than in biopsies. There was a positive correlation between IFN-γ and TNF in PBMCs, and an inverse correlation between TNF and IL-10 in the cells from the lesion site. A strong correlation between IL-1β, IL-17, and GzmB was observed in the biopsies, and a positive correlation was detected between these cytokines and the lesion size. Our results indicate that the immune response in L. braziliensis lesions is different from that observed in peripheral blood, and our data suggest that in addition to IL-1β and GzmB, IL-17 participates in the pathology of CL.

Characterisation of an area of coexistent visceral and cutaneous leishmaniasis transmission in the State of Piauí, Brazil

BACKGROUND

In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area.

OBJECTIVES

This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area.

METHODS

In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors.

FINDINGS

The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA.

MAIN CONCLUSION

Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.

Uncommon presentation of cutaneous leishmaniasis: late-onset facial involvement after a decade-a rare case report

Leishmaniasis is a parasitic infection that can involve the skin, mucosal membranes, and internal organs. It is endemic to the tropics. A forty-three-year-old male, diagnosed and treated for visceral leishmaniasis 15 years ago, presented with a complaint of a progressively growing lesion on his face for five years. A detailed history, clinical examination, and histopathological examination were done to reach a diagnosis of cutaneous leishmaniasis (CL). Treatment with oral fluconazole 300 mg daily for six months, followed by 50 mg miltefosine three times a day for another two months, led to complete resolution of symptoms, and the lesion on the face was cured. Early diagnosis is crucial to averting unwarranted treatment and potential complications. This case aims to inform clinicians of the high index of suspicion when diagnosing CL; given the delayed presentation, the previous medical history and the natural course of the lesion are of utmost importance.

Automated Identification of Cutaneous Leishmaniasis Lesions Using Deep-Learning-Based Artificial Intelligence

The polymorphism of cutaneous leishmaniasis (CL) complicates diagnosis in health care services because lesions may be confused with other dermatoses such as sporotrichosis, paracocidiocomycosis, and venous insufficiency. Automated identification of skin diseases based on deep learning (DL) has been applied to assist diagnosis. In this study, we evaluated the performance of AlexNet, a DL algorithm, to identify pictures of CL lesions in patients from Midwest Brazil. We used a set of 2458 pictures (up to 10 of each lesion) obtained from patients treated between 2015 and 2022 in the Leishmaniasis Clinic at the University Hospital of Brasilia. We divided the picture database into training (80%), internal validation (10%), and testing sets (10%), and trained and tested AlexNet to identify pictures of CL lesions. We performed three simulations and trained AlexNet to differentiate CL from 26 other dermatoses (e.g., chromomycosis, ecthyma, venous insufficiency). We obtained an average accuracy of 95.04% (Confidence Interval 95%: 93.81-96.04), indicating an excellent performance of AlexNet in identifying pictures of CL lesions. We conclude that automated CL identification using AlexNet has the potential to assist clinicians in diagnosing skin lesions. These results contribute to the development of a mobile application to assist in the diagnosis of CL in health care services.

Triose Phosphate Isomerase Structure-Based Virtual Screening and In Vitro Biological Activity of Natural Products as Leishmania mexicana Inhibitors

Cutaneous leishmaniasis (CL) is a public health problem affecting more than 98 countries worldwide. No vaccine is available to prevent the disease, and available medical treatments cause serious side effects. Additionally, treatment failure and parasite resistance have made the development of new drugs against CL necessary. In this work, a virtual screening of natural products from the BIOFACQUIM and Selleckchem databases was performed using the method of molecular docking at the triosephosphate isomerase (TIM) enzyme interface of Leishmania mexicana (L. mexicana). Finally, the in vitro leishmanicidal activity of selected compounds against two strains of L. mexicana, their cytotoxicity, and selectivity index were determined. The top ten compounds were obtained based on the docking results. Four were selected for further in silico analysis. The ADME-Tox analysis of the selected compounds predicted favorable physicochemical and toxicological properties. Among these four compounds, S-8 (IC50 = 55 µM) demonstrated a two-fold higher activity against the promastigote of both L. mexicana strains than the reference drug glucantime (IC50 = 133 µM). This finding encourages the screening of natural products as new anti-leishmania agents.

Erysipeloid Leishmaniasis: A Case Series

Cutaneous leishmaniasis can present in many different clinical forms. Diagnosis of atypical forms is often delayed. It is useful to keep in mind the diagnosis of cutaneous leishmaniasis, a mimicking disease, to reduce unnecessary treatment and patient morbidity. Erysipeloid leishmaniasis should be considered when presented as long-term erysipelas-like lesions that do not respond to antibiotics. We want to present our five patients with erysipeloid leishmaniasis, one of the atypical clinical forms.

Cutaneous Leishmaniasis in a Non-endemic Area in Mexico

Leishmaniasis is a zoonotic disease caused by a parasite of the genus Leishmania endemic in 102 countries around the world. Clinical features can be classified as cutaneous, mucocutaneous, and visceral leishmaniasis; this will depend on the species of leishmania responsible for the disease and the immunologic response of the host. We present the case of a 14-year-old male who started with a small papular lesion in the helix of the left ear, which later spread to the rest of the helix, tragus, and part of the auricular concha. On physical examination, an erythematous plaque with a scale that deforms the auricular surface was observed. In histopathology, acute and chronic inflammatory processes were observed with an accumulation of macrophages that contain amastigotes inside (Leishman Donovan bodies). The diagnosis of leishmaniasis represents a challenge in non-endemic regions. It is important to ask about travel history to endemic areas and perform assays to confirm the diagnosis and initiate treatment to prevent mortality and morbidity.

A systematic review of peptide-based serological tests for the diagnosis of leishmaniasis

Serological methods should meet the needs of leishmaniasis diagnosis due to their high sensitivity and specificity, economical and adaptable rapid diagnostic test format, and ease of use. Currently, the performances of serological diagnostic tests, despite improvements with recombinant proteins, vary greatly depending on the clinical form of leishmaniasis and the endemic area. Peptide-based serological tests are promising as they could compensate for antigenic variability and improve performance, independently of Leishmania species and subspecies circulating in the endemic areas. The objective of this systematic review was to inventory all studies published from 2002 to 2022 that evaluate synthetic peptides for serological diagnosis of human leishmaniases and also to highlight the performance (e.g., sensitivity and specificity) of each peptide reported in these studies. All clinical forms of leishmaniasis, visceral and tegumentary, and all Leishmania species responsible for these diseases were considered. Following PRISMA statement recommendations, 1,405 studies were identified but only 22 articles met the selection criteria and were included in this systematic review. These original research articles described 77 different peptides, of which several have promising performance for visceral or tegumentary leishmaniasis diagnosis. This review highlights the importance of and growing interest in synthetic peptides used for serological diagnosis of leishmaniases, and their performances compared to some widely used tests with recombinant proteins.

Clinical Manifestation of Cutaneous Leishmaniasis Following a Mechanical Trauma

Unusual skin ulcers frequently represent a diagnostic challenge. When the most common disease entities such as arterial, venous or diabetic ulcers have been excluded, the question of further differential diagnoses and procedures arises. Other possible causes include chronic inflammatory diseases, neoplasia, self-inflicted wounds, primary infectious diseases and physical/chemical damage to the skin. To narrow down the differential diagnoses, a detailed history of the patient is essential, which also needs to include events further back in time.

Exploration of ethylene glycol linked nitrofurantoin derivatives against Leishmania: Synthesis and in vitro activity

Leishmaniasis is a neglected tropical disease that is caused by the Leishmania parasite. It is estimated that there are more than 350 million people at risk of infection annually. Current treatments that are in clinical use are expensive, have toxic side effects, and are facing parasitic resistance. Therefore, new drugs are urgently required. In the quest for new, safe, and cost-effective drugs, a series of novel ethylene glycol derivatives of nitrofurantoin was synthesised and the in vitro antileishmanial efficacy of the compounds tested against Leishmania donovani and Leishmania major strains. Arylated ethylene glycol derivatives were found to be the most potent, with submicromolar activity up to 294-fold greater than the parent compound nitrofurantoin. Analogues 2j and 2k had the best antipromastigote activities with submicromolar IC₅₀ values against L. major IR-173 and antimonial-resistant L. donovani 9515 strains.

Novel Selective and Low-Toxic Inhibitor of LmCPB2.8ΔCTE (CPB) One Important Cysteine Protease for Leishmania Virulence

Leishmaniasis is a highly prevalent, yet neglected disease caused by protozoan parasites of the genus Leishmania. In the search for newer, safer, and more effective antileishmanial compounds, we herein present a study of the mode of action in addition to a detailed structural and biological characterization of LQOF-G6 [N-benzoyl-N'-benzyl-N″-(4-tertbutylphenyl)guanidine]. X-ray crystallography and extensive NMR experiments revealed that LQOF-G6 nearly exclusively adopts the Z conformation stabilized by an intramolecular hydrogen bond. The investigated guanidine showed selective inhibitory activity on Leishmania major cysteine protease LmCPB2.8ΔCTE (CPB) with ~73% inhibition and an IC50-CPB of 6.0 µM. This compound did not show any activity against the mammalian homologues cathepsin L and B. LQOF-G6 has been found to be nontoxic toward both organs and several cell lines, and no signs of hepatotoxicity or nephrotoxicity were observed from the analysis of biochemical clinical plasma markers in the treated mice. Docking simulations and experimental NMR measurements showed a clear contribution of the conformational parameters to the strength of the binding in the active site of the enzyme, and thus fit the differences in the inhibition values of LQOF-G6 compared to the other guanidines. Furthermore, the resulting data render LQOF-G6 suitable for further development as an antileishmanial drug.

Limitations of current chemotherapy and future of nanoformulation-based AmB delivery for visceral leishmaniasis-An updated review

Visceral leishmaniasis (VL) is the most lethal of all leishmaniasis diseasesand the second most common parasiticdisease after malaria and,still, categorized as a neglected tropical disease (NTD). According to the latest WHO study, >20 Leishmania species spread 0.7-1.0 million new cases of leishmaniasis each year. VL is caused by the genus, Leishmania donovani (LD), which affects between 50,000 and 90,000 people worldwide each year. Lack of new drug development, increasing drug resistance, toxicity and high cost even with the first line of treatmentof Amphotericin B (AmB), demands new formulation for treatment of VLFurther the lack of a vaccine, allowedthe researchers to develop nanofomulation-based AmB for improved delivery. The limitation of AmB is its kidney and liver toxicity which forced the development of costly liposomal AmB (AmBisome) nanoformulation. Success of AmBisome have inspired and attracted a wide range of AmB nanoformulations ranging from polymeric, solid lipid, liposomal/micellar, metallic, macrophage receptor-targetednanoparticles (NP) and even with sophisticated carbon/quantum dot-based AmBnano delivery systems. Notably, NP-based AmB delivery has shown increased efficacy due to increased uptake, on-target delivery and synergistic impact of NP and AmB. In this review, we have discussed the different forms of leishmaniasis disease and their current treatment options with limitations. The discovery, mechanism of action of AmB, clinical status of AmB and improvement with AmBisome over fungizone (AmB-deoxycholate)for VL treatment was further discussed. At last, the development of various AmB nanoformulation was discussed along with its adavantages over traditional chemotherapy-based delivery.

Cutaneous/Mucocutaneous Leishmaniasis Treatment for Wound Healing: Classical versus New Treatment Approaches

Cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (ML) show clinical spectra that can range from a localized lesion (with a spontaneous healing process) to cases that progress to a generalized systemic disease with a risk of death. The treatment of leishmaniasis is complex since most of the available drugs show high toxicity. The development of an effective topical drug formulation for CL and ML treatment offers advantages as it will improve patient’s compliance to the therapy given the possibility for self-administration, as well as overcoming the first pass metabolism and the high costs of currently available alternatives. The most common dosage forms include solid formulations, such as membranes and semi-solid formulations (e.g., ointments, creams, gels, and pastes). Topical treatment has been used as a new route of administration for conventional drugs against leishmaniasis and its combinations, as well as to exploit new substances. In this review, we discuss the advantages and limitations of using topical drug delivery for the treatment of these two forms of leishmaniasis and the relevance of combining this approach with other pharmaceutical dosage forms. Emphasis will also be given to the use of nanomaterials for site-specific delivery.

Genome-wide analysis reveals allelic variation and chromosome copy number variation in paromomycin-resistant Leishmania donovani

In the absence of adequate diagnosis and treatment, leishmaniasis remains a major public health concern on a global scale. Drug resistance remains a key obstacle in controlling and eliminating visceral leishmaniasis. The therapeutic gap due to lack of target-specific medicine and vaccine can be minimized by obtaining parasite's genomic information. This study compared whole-genome sequence of paromomycin-resistant parasite (K133PMM) developed through in vitro adaptation and selection with sensitive Leishmania clinical isolate (K133WT). We found a large number of upstream and intergenic gene variations in K133PMM. There were 259 single nucleotide polymorphisms (SNPs), 187 insertion-deletion (InDels), and 546 copy number variations (CNVs) identified. Most of the genomic variations were found in the gene's upstream and non-coding regions. Ploidy estimation revealed chromosome 5 in tetrasomy and 6, 9, and 12 in trisomy, uniquely in K133PMM. These contain the genes for protein degradation, parasite motility, autophagy, cell cycle maintenance, and drug efflux membrane transporters. Furthermore, we also observed reduction in ploidy of chromosomes 15, 20, and 23, in the resistant parasite containing mostly the genes for hypothetical proteins and membrane transporters. We chronicled correlated genomic conversion and aneuploidy in parasites and hypothesize that this led to rapid evolutionary changes in response to drug induced pressure, which causes them to become resistant.

Mucocutaneous Leishmaniasis due to Leishmania infantum Infection

Abstract is missing (Short communcation)

Parasites causing cutaneous wounds: Theory and practice from a dermatological point of view

A wide range of parasites can infest open wounds, or cause wounds due to the effects of the infestation. Parasitic infestations can involve the skin and subcutaneous tissues, with various clinical manifestations. In case of cutaneous wounds related to infestations, protozoa, helminths and arthropods are the main groups of parasites involved and emerging new aspects have been recently reported. Treating the wound correctly is fundamental in these patients in order to reduce the development of pathological scars and prevent complications. In particular, a gentle debridement for devitalized/infested tissue removal, the appropriate use of topical antiseptics and dressings such as hydrogel, hydrocolloids and antimicrobial dressings can be useful to control superinfections, moisture balance, inflammation and to promote edge proliferation.

Cutaneous leishmaniasis presenting with painless ulcer on the right forearm: A case report

BACKGROUND

Leishmaniasis includes a range of chronic infections in humans and animals and can be caused by more than 20 species of Leishmania protozoa. The manifestations of leishmaniasis are diverse and dependent on the immune response capacity of the host and the type of Leishmania. In East Asia, leishmaniasis is relatively rare and prone to misdiagnosis and underdiagnosis.

CASE SUMMARY

We report a case of a 36-year-old male with cutaneous leishmaniasis. The patient had been misdiagnosed with a bacterial skin infection and was given a dressing change and oral levofloxacin, which proved ineffective. Histopathological examination revealed amastigote (Leishman-Donovan body) in the histocytes, and nucleic acid sequencing proved that the pathogen was Leishmania major. The patient was treated successfully by regional injection of sodium gluconate (600 mg) three times. The ulcer healed and did not recur at 1.5-year follow-up.

CONCLUSION

Skin ulcers caused by leishmaniasis are easily misdiagnosed in non-epidemic countries, yet it should not be overlooked.

The clinical phenotypes of cutaneous leishmaniasis in central and Southwest Regions of Yemen

Background:

Cutaneous leishmaniasis (CL) is endemic in Yemen. CL displays a spectrum of typical and atypical morphologies yet understudied in the central and southwest regions of Yemen.

Aims and Objectives:

To identify the typical and atypical clinical phenotypes of CL in the central and southwest regions of Yemen.

Materials and Methods:

A survey of 145 patients who visited Prof. Al-Qubati Clinic in Taiz between 2010 and 2015, was conducted.

Results:

Children and residents of the rural areas were at high risk of exposure to the insect vector. The typical phenotype was single (67%), facial (58%) and ulcerated nodule (35%). Other usual phenotypes were small ulcers (21.4%) and non-ulcerative papules and nodules (21%). Unusual phenotypes constituted 12% of the cohort and included psoriasiform, eczematous, erysipeloid, lupoid, verrucous, large ulcerative, leishmania recidivens, satellite, granulomatous infiltrative and hyperkeratotic plaques. Mucous membrane involvement was evident in 10.6% and was also polymorphic.

Conclusion:

CL has many morphologic patterns in central and southwest regions of Yemen, some are clinically deceptive.

Atypical Cutaneous Leishmaniasis Variant

Leishmaniasis is a complex group of parasitic infectious diseases caused by intracellular protozoa of the genus Leishmania. It is a zoonosis mainly transmitted by the bite of infected female Phlebotomus or Lutzomyia sandflies. Clinical manifestations of leishmaniasis are diverse and can range from asymptomatic presentations to disseminated systemic disease. Cutaneous leishmaniasis is endemic in more than 80 countries in the world, having a predominance in tropical and subtropical regions. Although the majority of cases follow a classic development, an increasing number of new and rare variants of cutaneous leishmaniasis have been reported. These variants should be suspected as a cause of diverse clinical presentations, especially in endemic regions and travelers, being a diagnostic challenge for physicians.

We present a case of atypical cutaneous leishmaniasis found as a single verrucous plaque of eight months of evolution in the left posterior thigh of a 35-year-old man, who presented mild pruritus. The patient reported shrimp farming as his main occupational activity and was living in a rural region surrounded by forest on the Pacific coast of Ecuador. On dermatological examination, a single 4 x 5 cm verrucous plaque with irregular borders and a scaly erythematous violaceous aspect was found. Histopathological analysis revealed the presence of lymphohistiocytic inflammatory infiltrate with plasmocytes and granulomatous inflammation. On the Giemsa stain, intracellular amastigotes (Leishman-Donovan bodies) were observed. The treatment consisted of intramuscular meglumine antimoniate, presenting significant improvement on follow-up.

Advancement in leishmaniasis diagnosis and therapeutics: An update

Leishmaniasis is regarded as a neglected tropical disease by World Health Organization (WHO) and is ranked next to malaria as the deadliest protozoan disease. The primary causative agents of the disease comprise of diverse leishmanial species sharing clinical features ranging from skin abrasions to lethal infection in the visceral organs. As several Leishmania species are involved in infection, the role of accurate diagnosis becomes pivotal in adding new dimensions to anti-leishmanial therapy. Diagnostic methods must be fast, reliable, easy to perform, highly sensitive, and specific to differentiate among similar parasitic diseases. Herein, we present the conventional and recent approaches impended for the disease diagnosis and their sensitivity, specificity, and clinical application in parasite detection. Furthermore, we have also elaborated various new methods to cure leishmaniasis, which include host-directed therapies, drug repurposing, nanotechnology, and combinational therapy. This review addresses novel techniques and innovations in leishmaniasis, which can aid in unraveling new strategies to fight against the deadly infection.

From infection to vaccination: reviewing the global burden, history of vaccine development, and recurring challenges in global leishmaniasis protection

INTRODUCTION

Leishmaniasis is a major public health problem and the second most lethal parasitic disease in the world due to the lack of effective treatments and vaccines. Even when not lethal, leishmaniasis significantly affects individuals and communities through life-long disabilities, psycho-sociological trauma, poverty, and gender disparity in treatment.

AREAS COVERED

This review discusses the most relevant and recent research available on Pubmed and GoogleScholar highlighting leishmaniasis' global impact, pathogenesis, treatment options, and lack of effective control strategies. An effective vaccine is necessary to prevent morbidity and mortality, lower health care costs, and reduce the economic burden of leishmaniasis for endemic low- and middle-income countries. Since there are several forms of leishmaniasis, a pan-Leishmania vaccine without geographical restrictions is needed. This review also focuses on recent advances and common challenges in developing prophylactic strategies against leishmaniasis.

EXPERT OPINION

Despite advances in pre-clinical vaccine research, approval of a human leishmaniasis vaccine still faces major challenges - including manufacturing of candidate vaccines under Good Manufacturing Practices, developing well-designed clinical trials suitable in endemic countries, and defined correlates of protection. In addition, there is a need to explore Challenge Human Infection Model to avoid large trials because of fluctuating incidence and prevalence of leishmanasis.

Some Scaffolds as Anti-leishmanial Agents: An Review

Leishmaniasis is a parasitic infectious neglected tropical disease transmitted to humans by the parasites of Leishmania species. Mainly three types of leishmaniasis cases such as visceral (VL), cutaneous (CL) and mucocutaneous leishmaniasis are usually observed. In many western countries, almost 700,000 to 1million peoples are suffering from leishmaniasis and it is estimated that around 26000 to 65000 deaths occurs annually. For its treatment few drugs are available however none of them are ideal to treat leishmaniasis due to long treatment, discomfort mode of administration, risk of high level toxicity, high resistance against etc. Hence so many patients are unable to take complete treatment due to the high drug resistance. The present review will focus on antileishmanial activity of reported derivatives of betacarboline, chalcone, azole, quinoline, quinazoline, benzimidazole, benzadiazapine, thiaazoles, semicarbazone and hydontoin analogues. We believe that this present study will helpful to researcher to design new antileishmanial agents.

Cutaneous leishmaniasis: new oral therapeutic approaches under development

The World Health Organization (WHO) classifies leishmaniasis as a disease for which the development of new treatments is a priority. Available drugs are not fully effective in all cases; they have parenteral administration and exhibit serious and common adverse effects. The only oral drug available (miltefosine) has shown resistance, is expensive, and is not available in many endemic countries. Thus, the development of an oral medicine may solve many of these issues. Based on that, this review aimed to investigate which therapeutic alternatives have been studied for the development of oral drugs for the treatment of cutaneous leishmaniasis. A literature search for keywords "leishmania and oral" was performed in PubMed and ScienceDirect, considering articles published in the last 5 years. The articles were selected based on the objective of the review. The main problem in the current treatment of leishmaniasis is the administration of injectables, since it requires patients to travel to health centers, hospitalization, and professional administration, conditions that are not adapted to the socioeconomic reality of patients. Therefore, many research studies have evaluated oral alternatives for the treatment of cutaneous leishmaniasis. The main tested approaches were obtaining new molecules, repositioning drugs, and new formulations of old drugs. The prospects are encouraging but still require more in vivo bioavailability and clinical trials.

Reversed Immunoglycomics Identifies α-Galactosyl-Bearing Glycotopes Specific for Leishmania major Infection

All healthy humans have high levels of natural anti-α-galactosyl (α-Gal) antibodies (elicited by yet uncharacterized glycotopes), which may play important roles in immunoglycomics: (a) potential protection against certain parasitic and viral zoonotic infections; (b) targeting of α-Gal-engineered cancer cells; (c) aiding in tissue repair; and (d) serving as adjuvants in α-Gal-based vaccines. Patients with certain protozoan infections have specific anti-α-Gal antibodies, elicited against parasite-derived α-Gal-bearing glycotopes. These glycotopes, however, remain elusive except for the well-characterized glycotope Galα1,3Galβ1,4GlcNAcα, expressed by Trypanosoma cruzi. The discovery of new parasitic glycotopes is greatly hindered by the enormous structural diversity of cell-surface glycans and the technical challenges of classical immunoglycomics, a top-down approach from cultivated parasites to isolated glycans. Here, we demonstrate that reversed immunoglycomics, a bottom-up approach, can identify parasite species-specific α-Gal-bearing glycotopes by probing synthetic oligosaccharides on neoglycoproteins. This method was tested here seeking to identify as-yet unknown glycotopes specific for Leishmania major, the causative agent of Old-World cutaneous leishmaniasis (OWCL). Neoglycoproteins decorated with synthetic α-Gal-containing oligosaccharides derived from L. major glycoinositolphospholipids served as antigens in a chemiluminescent enzyme-linked immunosorbent assay using sera from OWCL patients and noninfected individuals. Receiver-operating characteristic analysis identified Galpα1,3Galfβ and Galpα1,3Galfβ1,3Manpα glycotopes as diagnostic biomarkers for L. major-caused OWCL, which can distinguish with 100% specificity from heterologous diseases and L. tropica-caused OWCL. These glycotopes could prove useful in the development of rapid α-Gal-based diagnostics and vaccines for OWCL. Furthermore, this method could help unravel cryptic α-Gal-glycotopes of other protozoan parasites and enterobacteria that elicit the natural human anti-α-Gal antibodies.

Nanoparticles Loaded with a New Thiourea Derivative: Development and In vitro Evaluation Against Leishmania amazonensis

BACKGROUND

Leishmaniasis is a neglected tropical disease caused by protozoa of the genus Leishmania. Current treatments are restricted to a small number of drugs that display both severe side effects and a potential for parasites to develop resistance. A new N-(3,4-methylenedioxyphenyl)-N'- (2-phenethyl) thiourea compound (thiourea 1) has shown promising in vitro activity against Leishmania amazonensis with an IC₅₀ of 54.14 μM for promastigotes and an IC₅₀ of 70 μM for amastigotes.

OBJECTIVE

To develop a formulation of thiourea 1 as an oral treatment for leishmaniasis, it was incorporated into Nanoparticles (NPs), a proven approach to provide long-acting drug delivery systems.

METHODS

Poly (D,L-Lactic-co-Glycolic Acid) (PLGA) polymeric NPs containing thiourea 1 were obtained through a nanoprecipitation methodology associated with solvent evaporation. The NPs containing thiourea 1 were characterized for Encapsulation Efficiency (EE%), reaction yield (% w/w), surface charge, particle size and morphology by Transmission Electron Microscopy (TEM).

RESULTS

NPs with thiourea 1 showed an improved in vitro leishmanicidal activity with a reduction in its cytotoxicity against macrophages (CC₅₀>100 μg/mL) while preserving its IC₅₀ against intracellular amastigotes (1.46 ± 0.09 μg/mL). This represents a parasite Selectivity Index (SI) of 68.49, which is a marked advancement from the reference drug pentamidine (SI = 30.14).

CONCLUSION

The results suggest that the incorporation into NPs potentiated the therapeutic effect of thiourea 1, most likely by improving the selective delivery of the drug to the phagocytic cells that are targeted for infection by L. amazonensis. This work reinforces the importance of nanotechnology in the acquisition of new therapeutic alternatives for oral treatments.

ENTPDases from Pathogenic Trypanosomatids and Purinergic Signaling: Shedding Light towards Biotechnological Applications

ENTPDases are enzymes known for hydrolyzing extracellular nucleotides and playing an essential role in controlling the nucleotide signaling via nucleotide/purinergic receptors P2. Moreover, ENTPDases, together with Ecto-5´-nucleotidase activity, affect the adenosine signaling via P1 receptors. These signals control many biological processes, including the immune system. In this context, ATP is considered as a trigger to inflammatory signaling, while adenosine (Ado) induces anti-inflammatory response. The trypanosomatids Leishmania and Trypanosoma cruzi, pathogenic agents of Leishmaniasis and Chagas Disease, respectively, have their own ENTPDases named "TpENTPDases," which can affect the nucleotide signaling, adhesion and infection, in order to favor the parasite. Besides, TpENTPDases are essential for the parasite nutrition, since the Purine De Novo synthesis pathway is absent in them, which makes these pathogens dependent on the intake of purines and nucleopurines for the Salvage Pathway, in which TpENTPDases also take place. Here, we review information regarding TpNTPDases, including their known biological roles and their effect on the purinergic signaling. We also highlight the roles of these enzymes in parasite infection and their biotechnological applications, while pointing to future developments.

Wegener's granulomatosis and differential diagnosis of mucosal leishmaniasis

Granulomatosis with polyangiitis with nasal septal perforation can be confused with infectious diseases such as mucosal leishmaniasis, so these cases warrant an in-depth study in order to provide the correct treatment. Among the main characteristics to consider to define a Wegener's granulomatosis as opposed to an infectious disease are vasculitis, lymphadenopathy, and sinusopathy.

Cutaneous and Mucocutaneous Leishmaniasis

Leishmaniasis is a chronic disease caused by flagellate protozoa of the genus Leishmania. It is a global disease, but most cases are seen in South America, the Mediterranean, and some areas of Asia and Africa. The 3 main types of leishmaniasis are cutaneous (the most common), mucocutaneous, and visceral (the most severe). Visceral leishmaniasis is also known as kala-azar. Leishmaniasis is diagnosed by demonstrating the presence of Leishmania amastigotes in clinical specimens using direct microscopic examination or molecular analysis. Various treatments exist, although the evidence supporting the options available for cutaneous leishmaniasis is weak. Both the classical presentation of leishmaniasis and our management of the disease have changed in recent decades because of acquired immune deficiency caused by conditions such as human immunodeficiency infection or the use of tumor necrosis factor inhibitors.

Cutaneous Leishmaniasis in an Immunocompromised Pediatric Patient With Acute Lymphoblastic Leukemia

Leishmaniasis is a protozoan disease caused by the parasite Leishmania. It is most common in developing countries. Its clinical presentation varies depending on several factors such as patient's immunity. Cutaneous leishmaniasis is one of the main types of leishmaniasis, it is known to be a great mimicker. When seen in immunodeficient populations, such as patients with acute lymphoblastic leukemia, it may present more aggressively and its diagnosis is challenging. We present a case of a five-year-old male with a history of acute lymphoblastic leukemia undergoing chemotherapy who developed papules evolving into ulcerated nodules on his left lower extremity. An initial smear for leishmaniasis was negative, the disease evolved and spread in an ascending fashion, while efforts were made finding a diagnosis. One-month later the smear was repeated and positive for leishmaniasis. Subsequently, therapy with Meglumine antimoniate was prescribed. The lesions healed with atrophic scarring without complications. Cutaneous leishmaniasis diagnostic methods are not standardized, limitations such as interpreter's expertise and patient's immunity state may play a role in delaying the diagnosis.