Unusual Observations in Leishmaniasis-An Overview

Many faces of cutaneous leishmaniasis

BACKGROUND

Our objective in this study is to determine the atypical clinical presentations of cutaneous leishmaniasis (CL) patients diagnosed in Şanlıurfa province.

METHODS

This retrospective study included 213 patients with atypical clinical presentations among 1751 patients diagnosed with CL between October 2019 and August 2022 in Şanlıurfa Oriental Boil Diagnosis and Treatment Center located in an endemic region for CL.

RESULTS

We found the prevalence of atypical CL to be 12.1%. The most common atypical lesions were lupoid 21 (9.8%), erysipeloid 16 (7.5%), impetiginous 16 (7.5%), recidivan 15 (7%), eczematous 15 (7%), ecthyma-like 13 (6.1%), pyoderma gangrenous-like 12 (5.6%), and sporotrichoid 12 (5.6%). Other lesions with atypical clinical presentations: chalazion-like, verrucous, dental sinus-like, psoriasiform, zosteriform, lymphoma-like, juvenile xanthogranuloma-like, volcano-like, paronychial, basal cell carcinoma-like, squamous cell carcinoma-like, herpes labialis-like, keratoacanthoma-like, chancriform, annular, lichenoid, mastocitoma-like, keloidal, epidermoid cyst-like, kaposi sarcoma-like, scar leishmaniasis, granulomatous cheilitis-like, mycetoma-like, molluscum contagiosum-like, discoid lupus erythematosus-like, and dermatofibroma-like.

CONCLUSIONS

In addition to the atypical clinical presentations previously reported, we also defined dermatofibroma-like, Kaposi sarcoma-like, dental sinus-like, juvenile xanthogranuloma-like, mastocytoma-like, and epidermoid cyst-like. It should be kept in mind that CL can clinically mimic many infectious, inflammatory, and neoplastic diseases, which should be considered in the differential diagnosis of long-term non-healing lesions, especially in endemic areas. Key message What is already known on this subject:  CL is known as the great imitator disease in dermatology. What this study adds:  In addition to the atypical clinical presentations previously reported, we also defined dermatofibroma-like, Kaposi sarcoma-like, dental sinus-like, juvenile xanthogranuloma-like, mastocytoma-like, and epidermoid cyst-like. How this study might affect research, practice, or policy:  CL can clinically mimic many infectious, inflammatory and neoplastic diseases, which should be considered in the differential diagnosis of long-term non-healing lesions, especially in endemic areas.

Overview of Research on Leishmaniasis in Africa: Current Status, Diagnosis, Therapeutics, and Recent Advances Using By-Products of the Sargassaceae Family

Leishmaniasis in Africa, which has been designated as a priority neglected tropical disease by various global organizations, exerts its impact on millions of individuals, primarily concentrated within this particular region of the world. As a result of the progressively grave epidemiological data, numerous governmental sectors and civil organizations have concentrated their endeavors on this widespread outbreak with the objective of devising appropriate remedies. This comprehensive examination delves into multiple facets of this parasitic ailment, scrutinizing the associated perils, diagnostic intricacies, and deficiencies within the existing therapeutic protocols. Despite the established efficacy of current treatments, they are not immune to deleterious incidents, particularly concerning toxicity and the emergence of parasitic resistance, thus accentuating the necessity of exploring alternative avenues. Consequently, this research not only encompasses conventional therapeutic approaches, but also extends its scope to encompass complementary and alternative medicinal techniques, thereby striving to identify innovative solutions. A particularly auspicious dimension of this study lies in the exploration of natural substances and by-products derived from some brown algae of the Sargassaceae family. These resources possess the potential to assume a pivotal role in the management of leishmaniasis.

Review of Leishmaniasis Treatment: Can We See the Forest through the Trees?

There are three known clinical syndromes of leishmaniasis: cutaneous (CL), mucocutaneous (MCL), and visceral disease (VL). In MCL and VL, treatment must be systemic (either oral or intravenous), while CL treatment options vary and include observation-only localized/topical treatment, oral medications, or parenteral drugs. Leishmaniasis treatment is difficult, with several factors to be considered. First, the efficacy of treatments varies among different species of parasites prevalent in different areas on the globe, with each species having a unique clinical presentation and resistance profile. Furthermore, leishmaniasis is a neglected tropical disease (NTD), resulting in a lack of evidence-based knowledge regarding treatment. Therefore, physicians often rely on case reports or case series studies, in the absence of randomized controlled trials (RCT), to assess treatment efficacy. Second, defining cure, especially in CL and MCL, may be difficult, as death of the parasite can be achieved in most cases, while the aesthetic result (e.g., scars) is hard to predict. This is a result of the biological nature of the disease, often diagnosed late in the course of disease (with possible keloid formation, etc.). Third, physicians must consider treatment ease of use and the safety profile of possible treatments. Thus, topical or oral treatments (for CL) are desirable and promote adherence. Fourth, the cost of the treatment is an important consideration. In this review, we aim to describe the diverse treatment options for different clinical manifestations of leishmaniasis. For each currently available treatment, we will discuss the various considerations mentioned above (efficacy, ease of use, safety, and cost).

Anti-leishmanial effects of Eryngium planum and Ecbilliun elaterum methanolic extract against Leishmania major

Leishmaniasis is a vector-borne disease, one of the most important neglected tropical diseases. Existing anti-leishmanial treatments are not effective for a long time and associated with toxic side effects so searching for a new, effective and safe alternative treatments against infectious diseases is greatly needed. This study is aimed to assess the leishmaniacidal effects of methanolic extracts of Eryngium planum (E. planum) and Ecbilliun elaterum (E. elaterum) on Leishmania major (L. major), In vitro. The selected plants were collected from northern areas of Iran. The methanolic extract from the aerial parts of plants were prepared using maceration methods. GC- Mass analysis was used to determine the compounds of the plants. Promastigotes of L. major was cultured in RPMI-1640 medium and the anti-leishmanial and cytotoxicity effects of extracts at concentrations of 100, 200, 400 and 800 µg/ml were assessed using MTT assay. The data obtained from gas chromatography revealed that α-Pinene, Caryophyllene oxide, β-Caryophyllene, Bicyclogermacrene and α-Bisabolol are the main compounds extracted from E. planum and α-Pinene, Germacrene D, Caryophyllene oxide, γ-Eudesmol and α-Bisabolol are the main components of E. elaterum. The results of MTT Assay revealed that E. planum at concentrations of 800 µg/ml after 24 h at 400 µg/ml after 48 h and the E. elaterium at concentrations of 800 µg/ml after 48 h at 400 µg/ml after 72 h had similar anti-leishmanial effects to the positive control. These results indicated that E. planum and E. elaterum are the potential sources for the discovery of novel anti-leishmanial treatments.

Understanding hypergammaglobulinemia in experimental or natural visceral leishmaniasis

Nonspecific hypergammaglobulinemia (HGG) occurs in symptomatic human visceral leishmaniasis (VL) caused by L. L. infantum. This study assessed this finding in experimental infection in hamsters and natural infection in dogs. The serum concentration of proteins, albumin and globulins was determined through the biuret and bromocresol green reaction, where the HGG was better expressed through the albumin/globulin (A/G) ratio. HGG was associated with a higher concentration of specific anti-glycan antibodies (BSA-G)/promastigote soluble extract (PSE) and the presence of circulating immune complexes (IC) by dissociative enzyme-linked immunoassay (ELISA). The study found monovalent IC in 37.9% (PSE) and 50% (BSA-G) of sera from infected hamsters, with increased frequency as the disease progressed. HGG was found in >60% of the samples in dogs with VL, associated with higher levels of specific immunoglobulin (Ig)A and IgM, but not IgG, determined using the PSE and BSA-G ELISA. HGG was associated with the presence of monovalent IC in 58.9% (PSE) and 63.4% (BSA-G) positive dog samples. HGG may result not only from the nonspecific activation of B cells, with greater production of specific and nonspecific antibodies, but also due to lower IgG excretion due to the presence of soluble monovalent IC. HGG correlates to the progression of VL and may be a marker for manifested disease.

Antileishmanial Effect of 1,5- and 1,8-Substituted Fused Naphthyridines

In the absence of a vaccine, there is a need to find new drugs for the treatment of neglected tropical diseases, such as leishmaniasis, that can overcome the many drawbacks of those currently used. These disadvantages include cost, the need to maintain a cold chain, the route of administration, the associated adverse effects and the generation of resistance. In this work we have evaluated the antileishmanial effect of 1,5- and 1,8-substituted fused naphthyridines through in vitro and ex vivo assays, using genetically modified axenic and intramacrophagic Leishmania infantum amastigotes. The toxicity of these compounds has been tested in the mammalian host cell using murine splenic macrophages, as well as in murine intestinal organoids (miniguts) in order to assess their potential for oral administration. The 1,8- derivatives showed greater leishmanicidal activity and the presence of a nitrogen atom in the fused ring to the naphthyridine was important to increase the activity of both types of molecules. The aromatization of the pyridine ring also had marked differences in the activity of the compounds.

In vitro effect of alpha-bisabolol and its synthetic derivatives on macrophages, promastigotes, and amastigotes of Leishmania amazonensis and Leishmania infantum

Cutaneous and visceral leishmaniasis are public health problems in Africa, Asia, Europe, and America. The treatment has a high cost and toxicity. Thus, this work aims to evaluate the leishmanicidal activity of alpha-bisabolol and its three synthetic derivatives, P1, P2, and P3, on the promastigotes and amastigotes Leishmania infantum and L. amazonensis forms. Alpha-bisabolol showed the lowest IC50 with 3.43 for L. amazonensis promastigotes, while P1 was the most toxic for L. infantum with an IC50 of 9.10. The derivative P3 was better for the amastigote form, with an IC50 of 3.39 for L. amazonensis. All the compounds effectively decreased the intracellular load of amastigote and its ability to turn promastigote again. Thus, alpha-bisabolol and its three synthetic derivatives were effective in their leishmanicidal activity. Therefore, it can be an option for developing new treatments against leishmaniasis.

Leishmanial activity of Brazilian brown propolis and its diterpenes

Propolis is a natural product widely used in folk medicine. Among its various applications, its antiparasitic properties stand out. Due to its great biodiversity, Brazil is a major producer of several types of propolis. This study proposes to evaluate the leishmanicidal properties of the hydroalcoholic extract of propolis collected in the southern region of Brazil (Brown propolis - HEBP) and its main isolated compounds: abietic acid (1), 13-epi-cupressic acid (2), 13-epi-torulosol (3), dehydroabietic acid (4), cis-communic acid (5) and ent-agatic acid (6). In general, the diterpenes did not show activity against the promastigotes of Leishmania (Leishmania) amazonensis at the evaluated concentrations. However, the HEBP was very active with an inhibition concentration of 50% at 8.32 µg/mL. Moreover, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) assays showed morphological and structural alterations in promastigote forms of L. (L.) amazonensis when incubated with HEBP.

Delayed diagnosis among patients with visceral leishmaniasis

We aimed to estimate the diagnostic latency of patients with visceral leishmaniasis (VL). A monocentric retrospective observational study was conducted including all confirmed cases of VL diagnosed from January 2005 to March 2022. Epidemiological and clinical characteristics of patients with VL were collected. The diagnostic latency was defined as the number of days between the first contact with a health-care provider for signs and/or symptoms referable to VL and the laboratory diagnosis of leishmaniasis. Twenty-four cases of VL were included in the study, mostly male (75%) and Italians (79.2%), with a median age of 40 years [Inter Quartile Range (IQR 30-48)]. Fourteen (58.3%) VL cases were people living with HIV (PLWH) and 4 (16.6%) subjects were on immunosuppressive therapy. For VL the median diagnostic latency was 54 days (IQR 28-162). The shorter diagnostic latency was observed in PLWH [31 days (IQR 20-47)] followed by immunocompetent patients [160 days (IQR 133-247)] and those on immunosuppressive therapy [329 days (IQR 200-678)]. Twelve patients (50%) reported at least one medical encounter before the diagnosis of VL and 6 patients received a wrong therapy. Diagnostic delay in VL was significant in patients under immune suppressive treatment.

Diagnostic Tools for Cutaneous Leishmaniasis Caused by Leishmania donovani: A Narrative Review

Leishmaniasis, a neglected tropical disease, encompasses a spectrum of clinical conditions and poses a significant risk of infection to over one billion people worldwide. Visceral leishmaniasis (VL) in the Indian sub-continent (ISC), where the causative parasite is Leishmania donovani, is targeted for elimination by 2025, with some countries already reaching such targets. Other clinical phenotypes due to the same species could act as a reservoir of parasites and thus pose a challenge to successful control and elimination. Sri Lanka has consistently reported cutaneous leishmaniasis (CL) due to L. donovani as the primary disease presentation over several decades. Similar findings of atypical phenotypes of L. donovani have also been reported from several other countries/regions in the Old World. In this review, we discuss the applicability of different methods in diagnosing CL due to L. donovani and a comprehensive assessment of diagnostic methods spanning clinical, microscopic, molecular, and immunological approaches. By incorporating evidence from Sri Lanka and other regions on L. donovani-related CL, we thoroughly evaluate the accuracy, feasibility, and relevance of these diagnostic tools. We also discuss the challenges and complexities linked to diagnosing CL and review novel approaches and their applicability for detecting CL.

A Rare Case of Imported Cutaneous Leishmaniasis Caused by Leishmania infantum in the Republic of Korea, 2021

Leishmaniasis is a neglected tropical disease and an infectious disease transmitted by sandflies that occurs worldwide. In the absence of physicians seeking to identify the causes of disease in non-endemic areas, appropriate diagnoses cannot be made, thereby hampering effective treatment. In this report, we examined a nodular lesion on a patient's chin by performing a biopsy and molecular analysis. The biopsy finding led to the identification of a Leishmania amastigote. On the basis of PCR analysis of the internal transcribed spacer 1 gene and 5.8 S ribosomal RNA with a subsequent BLAST search, we identified the causal organism as Leishmania infantum. The patient, who had visited Spain from 1 July to 31 August 2018, was accordingly diagnosed with cutaneous leishmaniasis and was administered liposomal amphotericin B, which successfully treated the skin lesion. Travel history plays an important role in the diagnosis of leishmaniasis, and physicians should bear in mind that travelers can also introduce diseases and pathogens to non-endemic areas. Identification of Leishmania at the species level will increase the efficacy of treatment.