Treatment of cutaneous leishmaniasis: retrospectives and advances for the 21st century

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).

Impetiginous Cutaneous Leishmaniasis after COVID-19 Infection in a Patient with Poor Cardiac Profile: A Case Report and Literature Review

Cutaneous leishmaniasis incidence has been rising in the past couple of decades. Standard therapy often includes antileishmanial drugs; however, due to their low safety and toxicity threshold, alternative treatments are being investigated. The association between COVID-19 and cutaneous leishmaniasis remains unclear and exploring this connection may offer crucial insights into the pathophysiology of and treatment strategies for infected patients. In this article, we describe a case of a male patient with a history of cardiac and other comorbidities who presented with cutaneous leishmaniasis in the form of impetigo-like skin lesions after being infected with COVID-19. Due to the patient's poor cardiac profile, sodium stibogluconate was not used and an alternative therapeutic approach was employed. The patient was treated with oral terbinafine, cryotherapy on specific lesions, and a course of cephalexin. Following the course of treatment and subsequent follow-up, the patient exhibited complete resolution and healing of the lesions with scarring, and no active lesions or recurrence were observed. This case highlights the potential for alternative treatment strategies for cutaneous leishmaniasis in patients with comorbidities and emphasizes the importance of further research to better understand the link between COVID-19 and cutaneous leishmaniasis.

Efficacy of Systemic Treatment for Leishmania tropica Cutaneous Leishmaniasis

The effectiveness of systemic treatment for Leishmania tropica cutaneous leishmaniasis remains unclear. The purpose of the study is to evaluate the efficacy and safety of systemic treatments for L. tropica cutaneous leishmaniasis. This retrospective study was performed in 114 patients. Systemic treatments included liposomal amphotericin B and sodium stibogluconate. All patients underwent systemic treatment for L. tropica cutaneous leishmaniasis. Favourable treatment responses were recorded in 72.5% and 70.2% of the patients in the liposomal amphotericin B and sodium stibogluconate groups, respectively; 25.3% and 46% of those in the liposomal amphotericin B and sodium stibogluconate groups respectively, experienced at least one adverse effect. Lesions in cartilaginous areas were associated with higher treatment failure. Prior topical or systemic treatment increased the chance of future systemic treatment success. Liposomal amphotericin B was associated with a shorter intravenous treatment duration and better safety profile. Thus, liposomal amphotericin B is the treatment of choice for L. tropica cutaneous leishmaniasis.

Treating leishmaniasis in Amazonia, part 2: Multi-target evaluation of widely used plants to understand medicinal practices

ETHNOPHARMACOLOGICAL RELEVANCE

Leishmaniasis are widely distributed among tropical and subtropical countries, and remains a crucial health issue in Amazonia. Indigenous groups across Amazonia have developed abundant knowledge about medicinal plants related to this pathology.

AIM OF THE STUDY

We intent to explore the weight of different pharmacological activities driving taxa selection for medicinal use in Amazonian communities. Our hypothesis is that specific activity against Leishmania parasites is only one factor along other (anti-inflammatory, wound healing, immunomodulating, antimicrobial) activities.

MATERIALS AND METHODS

The twelve most widespread plant species used against leishmaniasis in Amazonia, according to their cultural and biogeographical importance determined through a wide bibliographical survey (475 use reports), were selected for this study. Plant extracts were prepared to mimic their traditional preparations. Antiparasitic activity was evaluated against promastigotes of reference and clinical New-World strains of Leishmania (L. guyanensis, L. braziliensis and L. amazonensis) and L. amazonensis intracellular amastigotes. We concurrently assessed the extracts immunomodulatory properties on PHA-stimulated human PBMCs and RAW264.7 cells, and on L. guyanensis antigens-stimulated PBMCs obtained from Leishmania-infected patients, as well as antifungal activity and wound healing properties (human keratinocyte migration assay) of the selected extracts. The cytotoxicity of the extracts against various cell lines (HFF1, THP-1, HepG2, PBMCs, RAW264.7 and HaCaT cells) was also considered. The biological activity pattern of the extracts was represented through PCA analysis, and a correlation matrix was calculated.

RESULTS

Spondias mombin L. bark and Anacardium occidentale L. stem and leaves extracts displayed high anti-promatigotes activity, with IC₅₀ ≤ 32 μg/mL against L. guyanensis promastigotes for S. mombin and IC₅₀ of 67 and 47 μg/mL against L. braziliensis and L. guyanensis promastigotes, respectively, for A. occidentale. In addition to the antiparasitic effect, antifungal activity measured against C. albicans and T. rubrum (MIC in the 16-64 μg/mL range) was observed. However, in the case of Leishmania amastigotes, the most active species were Bixa orellana L. (seeds), Chelonantus alatus (Aubl.) Pulle (leaves), Jacaranda copaia (Aubl.) D. Don. (leaves) and Plantago major L. (leaves) with IC₅₀ < 20 μg/mL and infection rates of 14-25% compared to the control. Concerning immunomodulatory activity, P. major and B. orellana were highlighted as the most potent species for the wider range of cytokines in all tested conditions despite overall contrasting results depending on the model. Most of the species led to moderate to low cytotoxic extracts except for C. alatus, which exhibited strong cytotoxic activity in almost all models. None of the tested extracts displayed wound healing properties.

CONCLUSIONS

We highlighted pharmacologically active extracts either on the parasite or on associated pathophysiological aspects, thus supporting the hypothesis that antiparasitic activities are not the only biological factor useful for antileishmanial evaluation. This result should however be supplemented by in vivo studies, and attracts once again the attention on the importance of the choice of biological models for an ethnophamacologically consistent study. Moreover, plant cultural importance, ecological status and availability were discussed in relation with biological results, thus contributing to link ethnobotany, medical anthropology and biology.

Health economic evaluation of moist wound care in chronic cutaneous leishmaniasis ulcers in Afghanistan

Background

The present health economic evaluation in Afghanistan aims to support public health decision makers and health care managers to allocate resources efficiently to appropriate treatments for cutaneous leishmaniasis (CL) elicited by Leishmania tropica or Leishmania major.

Methods

A decision tree was used to analyse the cost and the effectiveness of two wound care regimens versus intra-lesional antimony in CL patients in Afghanistan. Costs were collected from a societal perspective. Effectiveness was measured in wound free days. The incremental cost-effectiveness ratio (ICER) and incremental net monetary benefit (NMB) were calculated. The model was parameterized with baseline parameters, sensitivity ranges, and parameter distributions. Finally, the model was simulated and results were evaluated with deterministic and probability sensitivity analyses. Final outcomes were the efficiency of the regimens and a budget impact analysis in the context of Afghanistan.

Results

Average costs per patients were US$ 11 (SE = 0.016) (Group I: Intra-dermal Sodium Stibogluconate [IL SSG]), US$ 16 (SE = 7.58) (Group II: Electro-thermo-debridement [ETD] + Moist wound treatment [MWT]) and US$ 25 (SE = 0.48) (Group III: MWT) in patients with a single chronic CL ulcer. From a societal perspective the budget impact analysis shows that the regimens’ drug costs are lower than indirect disease cost. Average effectiveness in wound free days are 177 (SE = 0.36) in Group II, 147 (SE = 0.33) in Group III, and 129 (SE = 0.27) in Group I. The ICER of Group II versus Group I was US$ 0.09 and Group III versus Group I US$ 0.77, which is very cost-effective with a willingness-to-pay threshold of US$ 2 per wound free day. Within a Monte-Carlo probabilistic sensitivity analysis Group II was cost-effective in 80% of the cases starting at a willingness-to-pay of 80 cent per wound free day.

Conclusions

Group II provided the most cost-effective treatment. The non-treatment alternative is not an option in the management of chronic CL ulcers. MWT of Group III should at least be practiced. The cost-effectiveness of Group III depends on the number of dressings necessary until complete wound closure.

Electronic supplementary material

The online version of this article (doi: 10.1186/s40249-018-0389-4) contains supplementary material, which is available to authorized users.

Leishmaniasis in humans: drug or vaccine therapy?

Leishmania is an obligate intracellular pathogen that invades phagocytic host cells. Approximately 30 different species of Phlebotomine sand flies can transmit this parasite either anthroponotically or zoonotically through their bites. Leishmaniasis affects poor people living around the Mediterranean Basin, East Africa, the Americas, and Southeast Asia. Affected regions are often remote and unstable, with limited resources for treating this disease. Leishmaniasis has been reported as one of the most dangerous neglected tropical diseases, second only to malaria in parasitic causes of death. People can carry some species of Leishmania for long periods without becoming ill, and symptoms depend on the form of the disease. There are many drugs and candidate vaccines available to treat leishmaniasis. For instance, antiparasitic drugs, such as amphotericin B (AmBisome), are a treatment of choice for leishmaniasis depending on the type of the disease. Despite the availability of different treatment approaches to treat leishmaniasis, therapeutic tools are not adequate to eradicate this infection. In the meantime, drug therapy has been limited because of adverse side effects and unsuccessful vaccine preparation. However, it can immediately make infections inactive. According to other studies, vaccination cannot eradicate leishmaniasis. There is no perfect vaccine or suitable drug to eradicate leishmaniasis completely. So far, no vaccine or drug has been provided to induce long-term protection and ensure effective immunity against leishmaniasis. Therefore, it is necessary that intensive research should be performed in drug and vaccine fields to achieve certain results.

Interventions for Old World cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis, caused by a parasitic infection, is considered one of the most serious skin diseases in many low- and middle-income countries. Old World cutaneous leishmaniasis (OWCL) is caused by species found in Africa, Asia, the Middle East, the Mediterranean, and India. The most commonly prescribed treatments are antimonials, but other drugs have been used with varying success. As OWCL tends to heal spontaneously, it is necessary to justify the use of systemic and topical treatments. This is an update of a Cochrane Review first published in 2008.

OBJECTIVES

To assess the effects of therapeutic interventions for the localised form of Old World cutaneous leishmaniasis.

SEARCH METHODS

We updated our searches of the following databases to November 2016: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs). We wrote to national programme managers, general co-ordinators, directors, clinicians, WHO-EMRO regional officers of endemic countries, pharmaceutical companies, tropical medicine centres, and authors of relevant papers for further information about relevant unpublished and ongoing trials. We undertook a separate search for adverse effects of interventions for Old World cutaneous leishmaniasis in September 2015 using MEDLINE.

SELECTION CRITERIA

Randomised controlled trials of either single or combination treatments in immunocompetent people with OWCL confirmed by smear, histology, culture, or polymerase chain reaction. The comparators were either no treatment, placebo/vehicle, and/or another active compound.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias and extracted data. We only synthesised data when we were able to identify at least two studies investigating similar treatments and reporting data amenable to pooling. We also recorded data about adverse effects from the corresponding search.

MAIN RESULTS

We included 89 studies (of which 40 were new to this update) in 10,583 people with OWCL. The studies included were conducted mainly in the Far or Middle East at regional hospitals, local healthcare clinics, and skin disease research centres. Women accounted for 41.5% of the participants (range: 23% to 80%). The overall mean age of participants was 25 years (range 12 to 56). Most studies lasted between two to six months, with the longest lasting two years; average duration was four months. Most studies were at unclear or high risk for most bias domains. A lack of blinding and reporting bias were present in almost 40% of studies. Two trials were at low risk of bias for all domains. Trials reported the causative species poorly.Here we provide results for the two main comparisons identified: itraconazole (200 mg for six to eight weeks) versus placebo; and paromomycin ointment (15% plus 10% urea, twice daily for 14 days) versus vehicle.In the comparison of oral itraconazole versus placebo, at 2.5 months' follow up, 85/125 participants in the itraconazole group achieved complete cure compared to 54/119 in the placebo group (RR 3.70, 95% CI 0.35 to 38.99; 3 studies; 244 participants). In one study, microbiological or histopathological cure of skin lesions only occurred in the itraconazole group after a mean follow-up of 2.5 months (RR 17.00, 95% CI 0.47 to 612.21; 20 participants). However, although the analyses favour oral itraconazole for these outcomes, we cannot be confident in the results due to the very low certainty evidence. More side effects of mild abdominal pain and nausea (RR 2.36, 95% CI 0.74 to 7.47; 3 studies; 204 participants) and mild abnormal liver function (RR 3.08, 95% CI 0.53 to 17.98; 3 studies; 84 participants) occurred in the itraconazole group (as well as reports of headaches and dizziness), compared with the placebo group, but again we rated the certainty of evidence as very low so are unsure of the results.When comparing paromomycin with vehicle, there was no difference in the number of participants who achieved complete cure (RR of 1.00, 95% CI 0.86, 1.17; 383 participants, 2 studies) and microbiological or histopathological cure of skin lesions after a mean follow-up of 2.5 months (RR 1.03, CI 0.88 to 1.20; 383 participants, 2 studies), but the paromomycin group had more skin/local reactions (such as inflammation, vesiculation, pain, redness, or itch) (RR 1.42, 95% CI 0.67 to 3.01; 4 studies; 713 participants). For all of these outcomes, the certainty of evidence was very low, meaning we are unsure about these results.Trial authors did not report the percentage of lesions cured after the end of treatment or speed of healing for either of these key comparisons.

AUTHORS' CONCLUSIONS

There was very low-certainty evidence to support the effectiveness of itraconazole and paromomycin ointment for OWCL in terms of cure (i.e. microbiological or histopathological cure and percentage of participants completely cured). Both of these interventions incited more adverse effects, which were mild in nature, than their comparisons, but we could draw no conclusions regarding safety due to the very low certainty of the evidence for this outcome.We downgraded the key outcomes in these two comparisons due to high risk of bias, inconsistency between the results, and imprecision. There is a need for large, well-designed international studies that evaluate long-term effects of current therapies and enable a reliable conclusion about treatments. Future trials should specify the species of leishmaniasis; trials on types caused by Leishmania infantum, L aethiopica, andL donovani are lacking. Research into the effects of treating women of childbearing age, children, people with comorbid conditions, and those who are immunocompromised would also be helpful.It was difficult to evaluate the overall efficacy of any of the numerous treatments due to the variable treatment regimens examined and because RCTs evaluated different Leishmania species and took place in different geographical areas. Some outcomes we looked for but did not find were degree of functional and aesthetic impairment, change in ability to detect Leishmania, quality of life, and emergence of resistance. There were only limited data on prevention of scarring.

Interventions for Old World cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis, caused by a parasitic infection, is considered one of the most serious skin diseases in many low- and middle-income countries. Old World cutaneous leishmaniasis (OWCL) is caused by species found in Africa, Asia, the Middle East, the Mediterranean, and India. The most commonly prescribed treatments are antimonials, but other drugs have been used with varying success. As OWCL tends to heal spontaneously, it is necessary to justify the use of systemic and topical treatments. This is an update of a Cochrane Review first published in 2008.

OBJECTIVES

To assess the effects of therapeutic interventions for the localised form of Old World cutaneous leishmaniasis.

SEARCH METHODS

We updated our searches of the following databases to November 2016: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs). We wrote to national programme managers, general co-ordinators, directors, clinicians, WHO-EMRO regional officers of endemic countries, pharmaceutical companies, tropical medicine centres, and authors of relevant papers for further information about relevant unpublished and ongoing trials. We undertook a separate search for adverse effects of interventions for Old World cutaneous leishmaniasis in September 2015 using MEDLINE.

SELECTION CRITERIA

Randomised controlled trials of either single or combination treatments in immunocompetent people with OWCL confirmed by smear, histology, culture, or polymerase chain reaction. The comparators were either no treatment, placebo/vehicle, and/or another active compound.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias and extracted data. We only synthesised data when we were able to identify at least two studies investigating similar treatments and reporting data amenable to pooling. We also recorded data about adverse effects from the corresponding search.

MAIN RESULTS

We included 89 studies (of which 40 were new to this update) in 10,583 people with OWCL. The studies included were conducted mainly in the Far or Middle East at regional hospitals, local healthcare clinics, and skin disease research centres. Women accounted for 41.5% of the participants (range: 23% to 80%). The overall mean age of participants was 25 years (range 12 to 56). Most studies lasted between two to six months, with the longest lasting two years; average duration was four months. Most studies were at unclear or high risk for most bias domains. A lack of blinding and reporting bias were present in almost 40% of studies. Two trials were at low risk of bias for all domains. Trials reported the causative species poorly.Here we provide results for the two main comparisons identified: itraconazole (200 mg for six to eight weeks) versus placebo; and paromomycin ointment (15% plus 10% urea, twice daily for 14 days) versus vehicle.In the comparison of oral itraconazole versus placebo, at 2.5 months' follow up, 85/125 participants in the itraconazole group achieved complete cure compared to 54/119 in the placebo group (RR 3.70, 95% CI 0.35 to 38.99; 3 studies; 244 participants). In one study, microbiological or histopathological cure of skin lesions only occurred in the itraconazole group after a mean follow-up of 2.5 months (RR 17.00, 95% CI 0.47 to 612.21; 20 participants). However, although the analyses favour oral itraconazole for these outcomes, we cannot be confident in the results due to the very low certainty evidence. More side effects of mild abdominal pain and nausea (RR 2.36, 95% CI 0.74 to 7.47; 3 studies; 204 participants) and mild abnormal liver function (RR 3.08, 95% CI 0.53 to 17.98; 3 studies; 84 participants) occurred in the itraconazole group (as well as reports of headaches and dizziness), compared with the placebo group, but again we rated the certainty of evidence as very low so are unsure of the results.When comparing paromomycin with vehicle, there was no difference in the number of participants who achieved complete cure (RR of 1.00, 95% CI 0.86, 1.17; 383 participants, 2 studies) and microbiological or histopathological cure of skin lesions after a mean follow-up of 2.5 months (RR 1.03, CI 0.88 to 1.20; 383 participants, 2 studies), but the paromomycin group had more skin/local reactions (such as inflammation, vesiculation, pain, redness, or itch) (RR 1.42, 95% CI 0.67 to 3.01; 4 studies; 713 participants). For all of these outcomes, the certainty of evidence was very low, meaning we are unsure about these results.Trial authors did not report the percentage of lesions cured after the end of treatment or speed of healing for either of these key comparisons.

AUTHORS' CONCLUSIONS

There was very low-certainty evidence to support the effectiveness of itraconazole and paromomycin ointment for OWCL in terms of cure (i.e. microbiological or histopathological cure and percentage of participants completely cured). Both of these interventions incited more adverse effects, which were mild in nature, than their comparisons, but we could draw no conclusions regarding safety due to the very low certainty of the evidence for this outcome.We downgraded the key outcomes in these two comparisons due to high risk of bias, inconsistency between the results, and imprecision. There is a need for large, well-designed international studies that evaluate long-term effects of current therapies and enable a reliable conclusion about treatments. Future trials should specify the species of leishmaniasis; trials on types caused by Leishmania infantum, L aethiopica, andL donovani are lacking. Research into the effects of treating women of childbearing age, children, people with comorbid conditions, and those who are immunocompromised would also be helpful.It was difficult to evaluate the overall efficacy of any of the numerous treatments due to the variable treatment regimens examined and because RCTs evaluated different Leishmania species and took place in different geographical areas. Some outcomes we looked for but did not find were degree of functional and aesthetic impairment, change in ability to detect Leishmania, quality of life, and emergence of resistance. There were only limited data on prevention of scarring.

Clinical study of cutaneous leishmaniasis in the Kashmir Valley

BACKGROUND

Cutaneous leishmaniasis (CL) is an infectious disease of tropical and semitropical areas of the world. The cold and harsh winter conditions of the Kashmir Valley do not favor the survival and growth of the Leishmania parasite or its vector, the sand fly, and the disease was until now practically unheard of in the Kashmir Valley.

AIMS

There has been a recent rise in the number of cases of CL in the Kashmir Valley. Against this background, the present study was taken up to describe the epidemiology, clinical features, and management outcomes of CL in the Kashmir Valley, where it represents a new phenomenon.

MATERIALS AND METHODS

Patients with direct smear-confirmed CL were evaluated. For each patient, we noted age, gender, geographical origin, stays in endemic areas, clinical aspects, number, site and size of lesions, treatment, and outcome. All the infected patients were treated with sodium stibogluconate. The dose, route of administration, adverse effects, and the clinical response in each patient was noted down.

RESULTS

Eighteen patients, 11 males (61.12%) and 7 females (38.88%) were studied. The age of the patients ranged from 3 to 60 years (mean age 29.8). The majority of our patients (16, 88.9%) belonged to two hilly areas, Uri and Karnah. Duration of the disease ranged from a minimum of 1 month to a maximum of 18 months (mean duration 4.6 months). Lesions in most of our patients (16, 88.9%) were located on the face including the lip and nose. The size of lesions varied from 4 to about 50 mm (average 2-3 cm). Most of our patients (13, 73.3%) had only a single lesion and a few (5, 26.7%) had two or three lesions. The clinical type of lesion in most of our patients (16, 88.9%) was noduloulcerative, only two (11.1%) had nodular (nonulcerative) lesions. Sixteen patients; all with facial lesions were treated with intravenous sodium stibogluconate. A complete response was seen in 14 (87%), without any major adverse effect. Two adult patients with extrafacial lesions were treated with four doses of weekly intralesional injections of sodium stibogluconate. A complete response was seen in both, without any major adverse effect.

CONCLUSION

The emergence of CL in this nonendemic area is of great epidemiological importance. Because no parasite isolation and characterization was carried out, further epidemiological studies and taxonomic differentiation of the species are required.

Therapeutic switching: from antidermatophytic essential oils to new leishmanicidal products

This study examined whether the antidermatophytic activity of essential oils (EOs) can be used as an indicator for the discovery of active natural products against Leishmania amazonensis. The aerial parts of seven plants were hydrodistilled. Using broth microdilution techniques, the obtained EOs were tested against three strains of dermatophytes (Trichophyton mentagrophytes, Microsporum gypseum and Microsporum canis). To compare the EOs antifungal and antiparasitic effects, the EOs activities against axenic amastigotes of L. amazonensis were concurrently evaluated. For the most promising EOs, their antileishmanial activities against parasites infecting peritoneal macrophages of BALB/c mice were measured. The most interesting antifungal candidates were the EOs from Cymbopogon citratus, Otacanthus azureus and Protium heptaphyllum, whereas O. azureus, Piper hispidum and P. heptaphyllum EOs exhibited the lowest 50% inhibitory concentration (IC₅₀) values against axenic amastigotes, thus revealing a certain correspondence between both activities. The P. hispidum EO was identified as the most promising product in the results from the infected macrophages model (IC₅₀: 4.7 µg/mL, safety index: 8). The most abundant compounds found in this EO were sesquiterpenes, notably curzerene and furanodiene. Eventually, the evaluation of the antidermatophytic activity of EOs appears to be an efficient method for identifying new potential drugs for the treatment of L. amazonensis.

Treatment of leishmaniasis in the Oyapock basin (French Guiana): A K.A.P. survey and analysis of the evolution of phytotherapy knowledge amongst Wayãpi Indians

ETHNOPHARMACOLOGICAL RELEVANCE

Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons.

MATERIALS AND METHODS

A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY).

RESULTS

The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study.

CONCLUSIONS

Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value.

Optimization of topical photodynamic therapy with 3,7-bis(di-n-butylamino)phenothiazin-5-ium bromide for cutaneous leishmaniasis

BACKGROUND AND OBJECTIVE

Photodynamic therapy (PDT) has evolved as a promising therapeutic measure for the treatment of cutaneous leishmaniasis (CL). In particular, phenothiazine compounds have demonstrated efficacy for PDT of CL. The objective of our present study is to define the use of a new specific phenothiazine photosensitizer, 3,7-bis(di-n-butylamino)phenothiazin-5-ium bromide (PPA904) applied topically as a cream to treat CL.

MATERIALS AND METHODS

To establish the optimal conditions for this treatment, we compared two different ways to improve current regimens of PDT with PPA904 cream (500 microM of PPA904 in Unguentum M) by changing the duration of topical application, and by administration of several consecutive PDT procedures. An initial regimen recommended by the manufacturer (Photopharmica Co. Ltd., Leeds, UK) was maintained as a control: the cream was applied topically for 30 minutes at a final concentration of PPA904 at 500 microM, and the designated treatment area was irradiated with a broad band light source of 665+/-15 nm at a fluence of 50 J/cm(2) (50 mW/cm(2)).

RESULTS

The best curative PPA904-PDT regimen was achieved under the conditions of a longer duration of topical application time (90 minutes) and several (three) consecutive treatments with 4-day intervals between treatments. The mechanisms responsible for such improvements (kinetics of drug penetration, depth of necrosis of the CL lesions after PDT, and daily changes in the parasitic load after PDT) are discussed in the present study.

CONCLUSION

Topical PPA904-PDT, implemented as described above, is a promising treatment for CL, and clinical studies will be initiated to establish efficacy in humans.

Interventions for Old World cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis is caused by a parasitic infection and is considered one of the most serious skin diseases in many developing countries. Antimonials are the most commonly prescribed treatment but other drugs have been used with varying success.

OBJECTIVES

To assess the effects of treatments for Old World cutaneous leishmaniasis (OWCL).

SEARCH STRATEGY

We searched the Cochrane Skin Group Specialised Register (April 2008), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2008), MEDLINE (2003-April 2008), EMBASE (2005-April 2008), CINAHL (1982-August 2007), LILACS (from inception to April 2008) and ongoing trials databases (August 2007).

SELECTION CRITERIA

Randomised controlled trials assessing treatments in immuno-competent people with OWCL confirmed by smear, histology, culture or polymerase chain reaction.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

We included 49 trials involving 5559 participants. Reporting quality was generally poor and only two studies contained sufficiently similar data to pool.In Leishmania major infections, there was good RCT evidence of benefit of cure around 3 months after treatment when compared to placebo for 200 mg oral fluconazole (1 RCT n = 200, RR 2.78; 95% CI 1.86, 4.16), topical 15% paromomycin + 12% methylbenzethonium chloride (PR-MBCL) (1 RCT n = 60, RR 3.09; 95% CI 1.14, 8.37) and photodynamic therapy (1 RCT n = 60, RR 7.02; 95% CI 3.80, 17.55). Topical PR-MBCL was less efficacious than photodynamic therapy (1 RCT n = 65, RR 0.44; 95% CI 0.29, 0.66). Oral pentoxifylline was a good adjuvant therapy to intramuscular meglumine antimoniate (IMMA) when compared to IMMA plus placebo (1 RCT n = 64, RR 1.63; 95% CI 1.11, 2.39)In Leishmania tropica infections, there was good evidence of benefit for the use of 200 mg oral itraconazole for 6 weeks compared with placebo (1 RCT n = 20, RR 7.00; 95% CI 1.04, 46.95), for intralesional sodium stibogluconate (1 RCT n = 292, RR 2.62; 95% CI 1.78, 3.86), and for thermotherapy compared with intramuscular sodium stibogluconate (1 RCT n = 283, RR 2.99; 95% CI 2.04, 4.37).

AUTHORS' CONCLUSIONS

Most trials have been designed and reported poorly, resulting in a lack of evidence for potentially beneficial treatments. There is a desperate need for large well conducted studies that evaluate long-term effects of current therapies. We suggest the creation of an international platform to improve quality and standardization of future trials in order to inform clinical practice.

Leishmania (Viannia) braziliensis: New primers for identification using polymerase chain reaction

The objective of this study was to develop specific primers for Leishmania (Viannia) braziliensis species identification using PCR. The designed primers (LBF1 and LBR1) were evaluated for sensitivity and specificity using various L. (V.) braziliensis serodemes and various Leishmania species and also using Trypanosoma cruzi. A specific fragment of 536bp was detected from 50ng of DNA in a crude extract derived from L. (V.) braziliensis. The DNA fragment was not detected when DNA from other Leishmania species or from T. cruzi was used as template in the PCR. Furthermore, when tested with DNA from cutaneous leishmaniasis the designed primers and reaction gave positive results. Taking into consideration that the primers LBF1 and LBR1 could specifically identify L. (V.) braziliensis, they could be considered for use in L. (V.) braziliensis diagnosis and epidemiological studies.

A rare case of leishmaniasis recidiva cutis evolving for 31 years caused by Leishmania tropica

A 64-year-old woman presented with erythematous, infiltrative plaques with a central atrophic area on both zygomatic regions. Several yellow-reddish papules were seen at the periphery of the plaques and showed an "apple-jelly" color on diascopy (Fig. 1). No visceral involvement was detected. The past medical history revealed that, at 3 years of age, she had developed an "Oriental sore" on both cheeks that healed with permanent scars. Thirty years later, she noticed an erythematous patch around the scars. She reported a hospital admission 22 years earlier for cutaneous leishmaniasis (CL); this was treated with pentavalent antimonial therapy for 10 days with partial improvement, when she refused further treatment. The lesions worsened in the summer and gradually became disfiguring, which prompted her to seek medical consultation. Laboratory findings were normal. Leishmania antibody titers were negative. Tissue samples were obtained by biopsy from the border of the lesion for culture, polymerase chain reaction (PCR), and histopathologic examination. Histology revealed a dermal infiltrate with tuberculoid granulomas surrounded by lymphocytes, histiocytes, and some plasma cells, but no caseation necrosis. A few Leishmania organisms were found on careful searching (Fig. 2). Leishmania tropica was identified by culture and PCR. A diagnosis of leishmaniasis recidiva cutis (LRC) was made on the basis of the anamnestic data together with the clinical, histopathologic, biologic, and molecular findings. Complete regression was achieved with meglumine antimoniate (Glucantime) given intramuscularly (15 mg Sb(V)/kg/day for 15 days) and cryosurgery with liquid nitrogen. No recurrence was noted during a 12-month follow-up period.

Cutaneous leishmaniasis: Clinical report of two cases and review of the recent literature

With 1-1.5 million cases reported every year cutaneous leishmaniasis represents an increasing health problem. The course of cutaneous leishmaniasis varies from a single self-healing ulcer to a persistent ulcer or progressive mucosal disease with nasopharyngeal destruction. An enormous array of topical and systemic treatment modalities has been endorsed. The response to treatment depends on the species of parasite as well as the host's immunological and genetic status. Species-specific treatment guidelines based on evidence from controlled studies are highly desirable. We present two cases of cutaneous leishmaniasis, one in a child and one during pregnancy, reviewing various diagnostic and therapeutic measures with special attention to problems in young and pregnant patients.

Effects of fluconazole on the pharmacokinetics and pharmacodynamics of antimony in cutaneous leishmaniasis-infected hamsters

Pentavalent antimony (Sb(V)) compounds are the drugs of choice for the treatment of all forms of leishmaniasis. For 20 years there has been an interest in antifungal azoles for treating leishmaniasis, with variable success. In the current study, we examined the effects of co-administration of fluconazole (FLZ) on the pharmacokinetics and pharmacodynamics of Sb(V) in cutaneous leishmaniasis-infected hamsters. Hamsters were divided into four groups. All hamsters were injected with 0.1 mL of 1x10(8)promastigotes/mL into the right foot on Day 1. Treatment was started 5 days after the infection. The antimony group received 80 mg/kg/day of Pentostam intramuscularly whilst the FLZ group received FLZ 20 mg/kg/day orally for 14 days. The combination group received both Pentostam and FLZ at the above mentioned doses for 14 days. Animals in the control group received no treatment. The infected footpads were measured on Days 1 and 14. A pharmacokinetic study was conducted on Days 1 and 14 of treatment, representing single- and multiple-dose pharmacokinetics, respectively. Blood samples were collected at different time intervals up to 24h. Sb(V) was determined using flameless atomic absorption spectrophotometry. Pharmacokinetic parameters were calculated using a non-compartmental analysis. In the single-dose study, there was no statistically significant difference in any of the pharmacokinetic parameters of Sb(V) when given alone or with FLZ. However, on Day 14 a significant increase in peak plasma concentration (C(max)) (three-fold) and area under the concentration-time curve (AUC) (four-fold) of antimony was observed when Sb(V) was co-administered with FLZ. A statistically significant prolongation of the terminal half-life from 1.63 to 8.67 h (P<0.05) was also observed. A significant reduction in clearance was detected. However, FLZ had no effect on the pharmacodynamics of Sb(V) as measured by footpad sizes. In conclusion, FLZ did not improve the therapeutic effect of Sb(V) when given concomitantly despite the significant increase in blood concentration and prolongation of the elimination half-life of Sb(V).

Cutaneous leishmaniasis treatment

The causative species of cutaneous leishmaniasis determines the clinical features and courses, and treatments. Intralesional or systemic antimonials are the gold standard for the treatment of these diseases. However, as for visceral leishmaniasis, other therapeutic options appear promising. Paromomycin ointments are effective in Leishmania major, L. tropica, L. mexicana, and L. panamensis lesions. In L. braziliensis localized leishmaniasis, both paromomycin and imiquimod may be topically applied. Oral fluconazole and zinc sulfate are useful in L. major. Oral azithromycin, effective in vitro and in mice, needs further investigation in human leishmaniasis. On the contrary, data with oral itraconazole are disappointing. Oral miltefosine, which is very effective in visceral leishmaniasis caused by L. donovani, appears ineffective in L. major and L. braziliensis infections. Intramuscular pentamidine is required for L. guyanensis cutaneous leishmaniasis, for which systemic antimony is not effective. Liposomal amphotericin B could be an alternative to antimony in south American cutaneous leishmaniasis with mucosal involvement (especially L. braziliensis and L. guyanensis infections).

Clinical features and diagnosis of 42 travellers with cutaneous leishmaniasis

BACKGROUND

Leishmania species that occur within different geographical areas may cause different clinical manifestations, virulence and drug sensitivity. Patients/Methods. All patients with a clinical diagnosis of cutaneous leishmaniasis seen at the Hospital for Tropical Diseases from 1997 to 2000 were identified and clinical details recorded onto a database, with emphasis on clinical presentation, risk factors, travel history and laboratory diagnosis.

RESULTS

Forty-two patients were identified, 23 of whom had travelled to New World and 19 to Old World countries. Clinical presentation typically consisted of a single nodule with ulceration. In 50% infection was caused by L. (Viannia) braziliensis. PCR was performed in specimens from 34 patients and species identification was possible in 32 cases (sensitivity 94%), the two PCR negative patients had amastigotes demonstrated by histology and culture. Patients were treated with established therapies. Seventy one percent were cured by treatment, 12% had a spontaneous cure, 7% were lost to follow-up and the remaining 10% required a second-line therapy. No relapses were reported during a mean follow-up period of 27 months.

CONCLUSIONS

Our study highlights the need for comprehensive investigations and the advantages of PCR in the diagnosis of patients with suspected leishmaniasis in non-endemic regions of the world.

Leishmania tropica in northern Israel: A clinical overview of an emerging focus

BACKGROUND

In Israel, most cutaneous leishmaniasis (CL) is caused by Leishmania major. Recently a new focus of CL caused by Leishmania tropica has been described in Tiberias and the surrounding area of northern Israel.

OBJECTIVE

The aim of this study was to evaluate clinical (size, number, location, and type of lesion) and laboratory (culture and polymerase chain reaction [PCR] analysis) parameters at diagnosis, response to treatment, and outcome of patients with CL due to L tropica.

METHODS

Between September 2002 and March 2004, patients with direct smear-confirmed CL were evaluated; clinical records were reviewed and a telephone survey was performed.

RESULTS

Forty nine patients, 34 (69%) male and 15 (31%) female, were studied. Mean age was 31.1 years (median 26 years, range 1-70); 76% of patients live in Tiberias and the surrounding area. The mean number of lesions was 2.6 (median 2, range 1-10). Lesions were commonly located on the face (61%) and upper limbs (57%). PCR analysis was performed in 27 patients and was positive for L tropica in 26. Fifty percent of patients studied received multiple therapeutic regimens because of incomplete response or treatment failure. Topical paromomycin was used in 44 patients (90%), with a complete response reported in only 17 (39%); of the 9 patients treated with intralesional sodium stibogluconate, a complete response was reported in 6 (67%); of the 5 patients treated with intravenous sodium stibogluconate, 4 (80%) were cured.

LIMITATIONS

The relatively small number of patients studied combined with the fact that some were assessed retrospectively limit our conclusions. In addition, 50% of the patients studied received multiple therapeutic regimens because of failure of, or incomplete responses to, their initial therapy, thereby making comparisons difficult.

CONCLUSIONS

The cure rate in those completing a course of antimony therapy, either 10 or more days of intravenous therapy or therapy administered intralesionally, was 75% (95% confidence interval [CI], 50.5-99.5%) as compared with 45% (95% CI, 28.9-60.5%) among those completing at least 10 days of topical paromomycin. To date, no standardized, simple, safe, and highly effective regimen for treating L tropica exists. Large, controlled clinical trials to evaluate current treatment regimens as well as new medications for CL, and especially CL attributed to L tropica, are urgently needed.

Leishmaniasis cutánea

Leishmaniases are diseases caused by infection by protozoa of the genus Leishmania. Cutaneous leishmaniasis caused by Leishmania infantum is frequent in Spain, especially in certain geographic areas. Diagnosis of cutaneous leishmaniasis is difficult because of the varied symptoms and because making cultures of this parasite is complicated. There are also different therapeutic, medical and surgical options, none of which is fully satisfactory. We review the most significant agents of cutaneous leishmaniasis in Spain.

Old world cutaneous leishmaniasis in Los Angeles: a case report, overview of the current literature, and guide for the treating dermatopathologist

We describe a case of cutaneous leishmaniasis in a Spanish patient visiting Los Angeles. Leishmania species cause both cutaneous and visceral disease; the majority of infections with Leishmania are of the cutaneous form. Although leishmaniasis is a relatively rare occurrence in the United States, travel by United States' citizens to endemic regions and increased United States military operations in the Middle East raise the chances of encountering cutaneous leishmaniasis. The following case report and overview of the current literature outlines the major morphologic findings and current diagnostic modalities available to diagnose cutaneous leishmaniasis.

Treatment of cutaneous leishmaniasis by photodynamic therapy

BACKGROUND

Cutaneous leishmaniasis represents a common health problem and standard treatments are often ineffective or yield poor cosmetic results.

OBJECTIVE

We compared the efficacy of photodynamic therapy (PDT) with paromomycin sulfate in 10 lesions of cutaneous leishmaniasis.

METHODS

Five lesions were treated by PDT with Metvix (Photocure, Oslo, Norway) and 75 J/cm(2) red light. PDT was performed twice weekly and, after 12 weeks, once weekly. The other 5 lesions were treated with paromomycin sulfate once daily. All nonresponding lesions of the paromomycin-treated plaques finally also underwent PDT.

RESULTS

All 5 lesions treated by PDT and 2 of the paromomycin sulfate-treated plaques were clinically and histologically Leishmania free. Three lesions with poor response to paromomycin sulfate finally responded to subsequent PDT. Ten months after therapy there was no recurrence, and cosmetic outcome after PDT was excellent.

CONCLUSION

PDT may be an effective therapeutic alternative in cutaneous leishmaniasis.

Cutaneous leishmaniasis in Sanliurfa: epidemiologic and clinical features of the last four years (1997-2000)

BACKGROUND

Sanliurfa is located in south-east Anatolia, the region with the largest focus of anthroponotic cutaneous leishmaniasis (CL) in Turkey. The present study was designed to determine the epidemiological and clinical patterns of cases of CL in the Sanliurfa area over a period of 4 years (1997-2000).

METHODS

2120 CL cases attending the Harrankapi in this study.

RESULTS

There were 790 cases of CL in 1997, and 778 in 1998. The numbers declined to 277 in 1999 and to 275 in 2000. The majority of patients (70%) were less than 20 years of age, with the highest percentage (27%) occurring in the 5- to 9-year age group. Acute CL and chronic CL were observed in 1926 (90.8%) and 63 (3%) patients, respectively. Leishmaniasis recidivans (LR) was found only in 131 (6.2%) patients. Lesions of CL were seen mainly on the exposed parts of the body such as the face and neck (57.5%), upper limbs (32.2%) and lower limbs (10.2%). Ninety-three percent of the patients were residents of central Sanliurfa from the southern and eastern parts of the city, areas with poor housing and low socio-economic conditions.

CONCLUSION

Although the incidence of CL showed a sharp decline from 1997 to 2000 in Sanliurfa, this does not mean that the disease is on its way to eradication.

Management of cutaneous leishmaniasis

There is an urgent need for a safe, effective, easily administered and cheap treatment for cutaneous leishmaniasis. Unfortunately it remains elusive. There have been a number of contributions during the last year, but none will change present day management. The diagnosis of cutaneous leishmaniasis is established on the basis of a typical lesion, a history of exposure and demonstration of the parasite. Molecular methods, usually based on kinetoplast DNA, are being developed and used increasingly to diagnose and type the infecting organism. Pentavalent antimonials remain the mainstay of treatment.

Structures of type 2 peroxisomal targeting signals in two trypanosomatid aldolases

Trypanosomatids, unicellular organisms responsible for several global diseases, contain unique organelles called glycosomes in which the first seven glycolytic enzymes are sequestered. We report the crystal structures of glycosomal fructose-1,6-bisphosphate aldolase from two major tropical pathogens, Trypanosoma brucei and Leishmania mexicana, the causative agents of African sleeping sickness and one form of leishmaniasis, respectively. Unlike mammalian aldolases, the T. brucei and L. mexicana aldolases contain nonameric N-terminal type 2 peroxisomal targeting signals (PTS2s) to direct their import into the glycosome. In both tetrameric trypanosomatid aldolases, the PTS2s from two different subunits form two closely intertwined structures. These "PTS2 dimers", which have very similar conformations in the two aldolase structures, are the first reported conformations of a glycosomal or peroxisomal PTS2, and provide opportunities for the design of trypanocidal compounds.