Case Report: Hyper IgM Syndrome Identified by Whole Genome Sequencing in a Young Syrian Man Presenting With Atypical, Severe and Recurrent Mucosal Leishmaniasis

A previously healthy 19-year-old Syrian man presented with atypical and severe mucosal leishmaniasis caused by Leishmania tropica. During a 2-year period, he had three severe relapses despite various treatment strategies, including liposomal amphotericin B and Miltefosine. Because of the unusual clinical presentation, potential underlying immunodeficiency was investigated. Normal T and NK cell counts were found. The B cell count was slightly elevated at 0.7 × 109 cells/L (0.09 × 109 to 0.57 × 109 cells/L), but the proportions of memory and isotype switched memory B cells were severely diminished IgG levels were low, at 309 mg/dL (610-1490 mg/dL). The initial IgM and IgA levels were within normal range, but the IgA levels decreased to 57 mg/dL (70-430 mg/dL) during follow up. Common variable immunodeficiency (CVID) was initially suspected, because the immunological results of low IgG and IgA, low switched memory B cells, no profound T cell deficiency found and absence of secondary cause of hypogammaglobulinemia were compatible with this diagnosis (ESID 2019). However, the highly unusual and severe clinical presentation of L. tropica is not suggestive of B-cell deficiency or CVID. Eventually a pathogenic nonsense variant in the CD40 ligand gene [p.(Arg11∗)] was identified by whole genome sequencing, thus enabling the diagnosis of X-linked hyper IgM syndrome. This case illustrates and supports the potential for the use of whole genome sequencing in accurate diagnosis of primary immunodeficiencies.

Interleukin-27 Functional Duality Balances Leishmania Infectivity and Pathogenesis

IL-27 is a cytokine that exerts diverse effects on the cells of innate and adaptive immune systems. Chiefly expressed in macrophages and dendritic cells during the early phase of Leishmania infection, IL-27 contributes to the protection against L. major infection but suppresses the protective Th1 response against L. donovani, L. infantum, L. amazonensis and L. braziliensis infections, suggesting its functional duality. During the late stage of Leishmania infection, IL-27 limits the immunopathogenic reactions and tissue damages. Herein, we analyze the mechanism of the functional duality of IL-27 in the resistance or susceptibility to Leishmania infection, prompting IL-27 for anti-Leishmanial therapy.

What's eating you? sand flies

As thousands of Americans descended upon Brazil for the Olympic games in the summer of 2016, the mosquito-borne Zika virus became a source of great concern among the countless athletes and travelers in Rio. As is often the case, the media frenzy that ensued drew travelers' attention away from a lesser known flying vector that often carries with it grave consequences. The Phlebotominae, commonly known as sand flies, are biting insects known for their ability to transmit the protozoa Leishmania as well as a number of other viruses and bacteria. As the impact of sand flies continues to grow in the United States and worldwide, knowledge of the vector is important for proper treatment and prevention of the diseases they carry.

Efficacy of Permethrin Treated Bed Nets Against Leishmania major Infected Sand Flies

Insecticide treated nets (ITNs) are a potential tool to help control sand flies and prevent Leishmaniasis. However, little is currently known about the response of Leishmania infected sand flies to ITNs. In this study, Phlebotomus duboscqi sand flies were infected with the parasite Leishmania major. Infected and noninfected sand flies were then evaluated against permethrin treated and untreated bed nets in a laboratory assay that required sand flies to pass through suspended netting material to feed on a mouse serving as an attractive host. The number of sand flies passing through the nets and blood feeding was recorded. There was not a significant difference in the ability of infected or noninfected sand flies to move through treated or untreated nets. Fewer sand flies entered the permethrin treated nets compared to the untreated nets, indicating that permethrin creates an effective barrier. The results show that in addition to reducing the nuisance bites of noninfected sand flies, ITNs also protect against Leishmania infected sand flies and therefore can play in key role in reducing the rates of Leishmaniasis. This study is important to the Department of Defense as it continues to develop and field new bed nets to protect service members.

Mucosal leishmaniasis: an underestimated presentation of a neglected disease

We present a review of current knowledge about mucosal leishmaniasis (ML). Although involvement of mucous membranes is classically admitted in New World leishmaniasis, particularly occurring in infection by Leishmania (L.) braziliensis species complex, ML is also a possible presentation of Old World leishmaniasis, in either L. donovani or L. major species complex infections. Thus, ML has to be considered not only as a Latin American disease but as an Old and New World disease. We describe ML epidemiology, pathogenesis, clinics, diagnosis, and therapy. Considering both its highly disfiguring lesions and its possible lethal outcome, ML should not be underestimated by physicians. Moreover, leishmaniasis is expected to increase its burden in many countries as sandfly vector distribution is widespreading towards non-endemic areas. Finally, the lack of clear understanding of ML pathogenesis and the absence of effective human vaccines strongly claim for more research.

Disseminated leishmaniasis in a four-year-old child in Yaoundé, Cameroon

Leishmaniasis is a disease caused by a protozoan parasite of the genus leishmania with worldwide distribution and is transmitted to man by phlebotomine sand flies. The clinical presentation could range from a single cutaneous ulcer to disseminated leishmaniasis. We report the case of a four-year-old boy admitted to our hospital with ulcers, wasting, progressively distending abdomen, and fatigue evolving for about two months. On admission, he was febrile and pale, with diffuse oozing wet ulcers on the limbs and face, hepatosplenomegaly, and enlarged inguinal lymph nodes. The complete blood count revealed pancytopenia with low reticulocyte count, and serum protein electrophoresis showed hypoalbuminemia and hypergammaglobulinemia. Skin biopsy revealed amastigotes in phagocytic cells. The above findings suggested cutaneous and visceral localization of the leishmania; however, the parents absconded with the boy just when treatment was instituted, believing that the child was bewitched. The outcome is expected to be fatal visceral involvement.

Leishmaniasis emergence in Europe

Leishmaniasis emergence in Europe is reviewed, based on a search of literature up to and including 2009. Topics covered are the disease, its relevance, transmission and epidemiology, diagnostic methods, treatment, prevention, current geographical distribution, potential factors triggering changes in distribution, and risk prediction. Potential factors triggering distribution changes include vectorial competence, importation or dispersal of vectors and reservoir hosts, travel, and climatic/environmental change. The risk of introducing leishmaniasis into the European Union (EU) and its spread among Member States was assessed for the short (2-3 years) and long term (15-20 years). There is only a low risk of introducing exotic Leishmania species because of the absence of proven vectors and/or reservoir hosts. The main threat comes from the spread of the two parasites endemic in the EU, namely Leishmania infantum, which causes zoonotic visceral and cutaneous leishmaniasis in humans and the domestic dog (the reservoir host), and L. tropica, which causes anthroponotic cutaneous leishmaniasis. The natural vector of L. tropica occurs in southern Europe, but periodic disease outbreaks in Greece (and potentially elsewhere) should be easily contained by surveillance and prompt treatment, unless dogs or other synanthropic mammals prove to be reservoir hosts. The northward spread of L. infantum from the Mediterranean region will depend on whether climate and land cover permit the vectors to establish seasonal biting rates that match those of southern Europe. Increasing dog travel poses a significant risk of introducing L. infantum into northern Europe, and the threat posed by non-vectorial dog-to-dog transmission should be investigated.

[PCR-RFLP and RAPD for typing neotropical Leishmania]

INTRODUCTION

The analysis of the PCR-restriction fragment length polymorphism and random amplified polymorphic DNA have been useful tools for Leishmania identification.

OBJECTIVES

Molecular procedures were demonstrated for identification and typing of reference strains of New World Leishmania and their applicability was validated for clinical samples.

MATERIALS AND METHODS

DNA was extracted from 16 reference strains of Latin American Leishmania as well as from clinical samples of leishmaniasis patients. A sequence coding for cysteine proteinase B was amplified by PCR and subjected to restriction fragment length polymorphism analysis. The enzyme used was Taq1. For eight of the reference strains, the random amplified polymorphic desoxyribonucleic acid technique (RAPD) was applied. Band patterns for Leishmania species differentiation were established each each method. The sample size of the clinical sample was of 5.

RESULTS

PCR products of the cysteine proteinase B gene were obtained for L. braziliensis, L. peruviana, L. panamensis and L. guyanensis. For the other species, L. mexicana, L. amazonensis, L. garnhami, L. lainsoni, L. chagasi, L. naiffi, no amplification occurred. The patterns of restriction fragments revealed band patterns in common for L. peruviana, L. guyanensis and L. panamensis, whereas L. braziliensis had a distinctive pattern. When human samples were examined, amplification occurred for all cases, and the profiles corresponded to the common profile of L. peruviana, L. guyanensis and L. panamensis. The RAPD technique demonstrated reproducible and distinctive patterns for each of the 8 reference strains, L. mexicana, L. amazonensis, L. garnhami, L. lainsoni, L. chagasi, L. naiffi, making possible to differentiate all them. The advantages and limitations of each procedure are discussed.

CONCLUSIONS

The combination of RFP and RAPD methodologies provide useful tools to identify medical important species of Leishmania by recognizing DNA sequences characteristic of each species.

Host and parasite factors influencing the expression of cutaneous leishmaniasis

Host and parasite factors influencing the expression of cutaneous leishmaniasis were investigated in two murine models of different leishmanial diseases. The role of B lymphocytes in the uncontrolled disease manifested by BALB/c mice infected with cutaneous leishmaniasis was investigated in animals of this inbred strain depleted of B cells by neonatal administration of anti-mouse mu-chain antisera. Whereas non-depleted control mice developed chronic metastatic infections with both Leishmania tropica and Leishmania mexicana and showed depressed delayed-type hypersensitivity when skin-tested with leishmanial antigens, the mu-suppressed mice controlled their initial lesions while displaying strong antigen-specific delayed-type hypersensitivity. These findings reveal an inverse relationship between humoral and cell-mediated immunity in the expression of chronic leishmaniasis and suggest that B lymphocytes or their products regulate the delayed-type hypersensitivity response to leishmanial infection. In a separate study, healing and chronic strains of Leishmania were compared for their susceptibility to killing by lymphokine-activated mouse peritoneal macrophages. Whereas amastigotes of the healing strains were readily destroyed by these macrophages, amastigotes of two Leishmania strains, previously shown to produce chronic infections in mice, were resistant to killing by the same cells. These findings suggest that the ability of certain leishmanial strains to induce chronic disease may result from their capacity to evade intracellular destruction by activated macrophages.

A review on the collection, preservation and systematic techniques in Phlebotominae

The aim of present study is to discuss the taxonomic and biological history and significance of Phlebotominae sand flies giving emphasis on their collection, preservation and identification of new species as well as differentiation of male and female. Several species of Phlebotominae sand flies are known throughout the world including India. These Phlebotominae sand flies are economically important natural enemies of human beings and cause Kala-azar and visceral leishmaniasis. This causes a lot of deaths. Taxonomy plays an important role in identifying these tiny insects accurately. The accurate identification is important to apply relevant control measures. A wrong identification may lead to misleading results and may upset the entire control strategy. From the start of sand fly research various methods for collection and identification were used. In the early twentieth century, the use of internal structures particularly, cibarium, pharynx and spermathecae was introduced as taxonomic characters. The identification of female sand flies was always found to be difficult and hence scanty work on females are available. Recently female external as well as internal genital structures are used for their identification. Another important character is the genital filament/spermathecal duct ratio which could be a good point for taxonomic differentiation of male and female Phlebotominae sand flies. The detailed study of some biologically important structures of sand flies e.g., mouthparts and reproductive organs both internal as well as external have led to the introduction of few new taxonomic characters.

Systemic hypertension in dogs with leishmaniasis: prevalence and clinical consequences

A prospective study was performed (November 1998 to December 2003) to determine the prevalence of systemic hypertension (SH) in dogs with glomerular disease secondary to leishmaniasis. One hundred and five dogs with leishmaniasis were screened and staged for the presence of renal disease (RD) and SH. For the purpose of the study, RD was defined as serum creatinine concentration > or = 1.4 mg/dL, a urine protein/creatinine ratio > or = 0.5, or both. SH was defined as a systolic blood pressure (SBP) > or =180 mm Hg or an SBP between 150 and 179 mm Hg in the presence of clinical manifestations of SH. Fifty-two (49.5%) of the dogs had some degree of RD, and 32 (61.5%) of these dogs were diagnosed with SH. Moreover, SH also was diagnosed in 3 dogs without RD. Left ventricular hypertrophy (LVH), estimated by echocardiography, was the most frequently observed systemic consequence of hypertension, being present in 32 (91.4%) of the hypertensive dogs. Echocardiographic abnormalities were not detected in any of the 33 dogs with leishmaniasis without RD, which were used as controls. Ocular consequences of SH were observed in only 2 (5.7%) of the dogs with hypertension. We conclude that SH is prevalent in dogs with RD secondary to leishmaniasis, not only in the more severe stages but also in the early course of the illness before azotemia becomes apparent. Canine leishmaniasis may be a useful natural model to study SH secondary to glomerular disease.

Zinc and infection: a review

Dietary zinc deficiency is widespread in developing countries and is often aggravated by intercurrent acute and chronic infections. Recent studies have demonstrated that zinc supplementation can significantly reduce the morbidity and mortality of apparently well-nourished children and shorten the time to recovery from acute infectious diseases. This review summarises current knowledge of the role of zinc in childhood diarrhoea, acute respiratory infections and malaria, and its potential role in diseases associated with impaired cellular immunity, namely tuberculosis, lepromatous leprosy and leishmaniasis, and explores avenues for future research.

[Immunopathogenesis of Leishmania infections]

Leishmaniasis represents a complex of diseases with a clinical and epidemiological diversity. Leishmaniasis remains a severe public health problem and its burden is increasing. The disease is caused by a parasite belonging to the genus Leishmania. Approximately 350 billion people in 88 different countries are thought to be infected with Leishmania spp. Clinical forms of leishmaniasis are particularly diverse representing different diseases: visceral (VL), cutaneous (CL), diffuse cutaneous (DCL) and muco-cutaneous (MCL) leishmaniasis. Being the most important determinant not only cellular immunity plays the essential role in the control of leishmaniasis, but the virulence, tropism and pathogenicity that is modulated by environmental and genetic factors of their mammalian hosts and sandfly vectors, are the key interactions. These eukaryotic pathogens have evolved with the vertebrate immune system and typically produce long lasting chronic infections. A critical step in their host interaction is the evasion of innate immune defenses. The ability to avoid attack by humoral effector mechanisms, such as complement lysis, and to resist killing by lysosomal enzymes and toxic metabolytes is of particular importance. They do so by remodelling the phagosomal compartments in which they reside and by interfering with signalling pathways that lead to cellular activation. In addition they modify the antigen presenting and immunoregulatory functions of dendritic cells, a process that fascilitates their evasion of both innate and adaptive immunity. Experimental animal studies revealed that these modifications and interference mechanisms led to two different pathogenesis schemes. For CL, the polarization of Th2/Th1 cells is responsible for the progression of the disease which than leads to the chronic-persistant state. The Th2/Th1 paradigm does not apply for visceral leishmaniasis. Immunosupression rather than polarization is responsible for the systemic and progressive outcome of the disease in VL. Based on experience with animal models and humans, new vaccine and novel immunotherapy strategies especially for the locations where the disease is endemic, hold promise for the near future. In this review article the immunopathogenesis of leishmaniasis has been discussed under the light of recent literature.

Oral miltefosine for leishmaniasis in immunocompromised patients: compassionate use in 39 patients with HIV infection

Oral miltefosine was administered to 39 human immunodeficiency virus (HIV)-infected patients with leishmaniasis for whom standard leishmaniasis treatment had failed. Initial response was achieved in 25 patients (64%), including 16 patients (43%) with initial parasitological cure. Repeated responses after relapse and tolerability of long courses of treatment indicate the potential for development of optimized dosage schemes.

IL-5–Induced Eosinophils Suppress the Growth ofLeishmania amazonensis In Vivoand Kill PromastigotesIn Vitroin Response to Either IL-4 or IFN-γ

In IL-5 transgenic mice (C3H/HeN-TgN(IL-5)-Imeg), in which 50% of peripheral blood leukocytes are eosinophils, the development of infection by Leishmania amazonensis was clearly suppressed. To determine mechanistically how this protozoan parasite is killed, we performed in vitro killing experiments. Either IL-4 or IFN-gamma effectively stimulated eosinophils to kill Leishmania amazonensis promastigotes, and most of the killing was inhibited by catalase but not by the NO inhibitor L-N5-(1-iminoethyl)-ornithine, suggesting that hydrogen peroxide is responsible for the killing of L. amazonensis by eosinophils. There was no significant degranulation of eosinophils in the culture, because eosinophil peroxidase was not detected in culture supernatants when L. amazonensis promastigotes were killed by activated eosinophils. Such resistance was also observed in BALB/c mice, which are highly susceptible to L. amazonensis. Expression plasmids for IL-4, IL-5, and IFN-gamma were transferred into muscle by electroporation in vivo starting 1 week before infection. Expression plasmid for IL-5 was most effective in slowing the development of infection among three expression plasmids. Expression plasmid for IL-4 was slightly effective and that for IFN-gamma had no effect on the progress of disease. These results suggest that IL-5 gene transfer into muscle by electroporation is useful as a supplementary protection method against L. amazonensis infection.

Leishmaniasis among soldiers of stabilization forces in Iraq. Review article

The results of studies concerning the incidence of leishmaniasis among soldiers of Stabilization Forces serving in Iraq in the years from 2003 to March 2004 are presented in this article, in the light of a possibility of importation of this disease to the countries of their origin. Epidemiology, clinical picture, laboratory diagnosis, treatment and prevention of leishmaniasis are described. In mid-2004, more than 2400 Polish soldiers served in Iraq. By the end of June 2004 no case of leishmaniasis was diagnosed among them. Among American troops serving in Iraq, 653 cases of cutaneous and 2 cases of visceral leishmaniasis were reported by the end of March 2004. According to the U.S. sources, the number of infected American soldiers could have been higher, from 750 to 1250 or even more, what made up to nearly 1% of U.S. troops serving in Iraq in 2003-2004.

Peridomestic risk factors for canine leishmaniasis in urban dwellings: new findings from a prospective study in Brazil

Despite the wealth of information on the prevalence and correlates of canine Leishmania infection (CLI), data on its incidence are still sparse, and little is known regarding risk factors for CLI. We studied a cohort of dogs in an urban area in Brazil to determine whether incidence varied with age, breed, and environmental characteristics. The mean follow-up was 1.5 years, and the crude incidence rate was 11.8 cases/100 dog-years (95% confidence interval [CI] = 8.6-15.6). In the multivariate analysis, short fur was the strongest predictor of CLI (relative risk [RR] = 9.4). In addition, our data indicate that raising pigs (RR = 4.1), chickens (RR = 3.3), or other livestock (RR = 2.6) significantly increased the risk of CLI. Thus, suggesting control measures directed towards modifying the environmental factors favoring contact between vectors, reservoirs, and susceptible humans, such as proximity to pigpens or hen houses. Furthermore, conventional control programs of insecticidal spraying of human dwellings should also apply insecticide in and around animal sheds.

Both the Fas ligand and inducible nitric oxide synthase are needed for control of parasite replication within lesions in mice infected with Leishmania major whereas the contribution of tumor necrosis factor is minimal

Following infection with the protozoan parasite Leishmania major, C57BL/6 mice develop a small lesion that heals spontaneously. Resistance to infection is associated with the development of CD4(+) Th1 cells producing gamma interferon (IFN-gamma) and tumor necrosis factor (TNF), which synergize in activating macrophages to their microbicidal state. We show here that C57BL/6 mice lacking both TNF and Fas ligand (FasL) (gld TNF(-/-) mice) infected with L. major neither resolved their lesions nor controlled Leishmania replication despite the development of a strong Th1 response. Comparable inducible nitric oxide synthase (iNOS) activities were detected in lesions of TNF(-/-), gld TNF(-/-), and gld mice, but only gld and gld TNF(-/-) mice failed to control parasite replication. Parasite numbers were high in gld mice and even more elevated in gld TNF(-/-) mice, suggesting that, in addition to iNOS, the Fas/FasL pathway is required for successful control of parasite replication and that TNF contributes only a small part to this process. Furthermore, FasL was shown to synergize with IFN-gamma for the induction of leishmanicidal activity within macrophages infected with L. major in vitro. Interestingly, TNF(-/-) mice maintained large lesion size throughout infection, despite being able to largely control parasite numbers. Thus, IFN-gamma, FasL, and iNOS appear to be essential for the complete control of parasite replication, while the contribution of TNF is more important in controlling inflammation at the site of parasite inoculation.

Mechanisms of pathogenesis: differences amongst Leishmania species

One of the features of the genus Leishmania is the diversity of tropism/disease resulting from infection. With notable exceptions, the form (visceral, cutaneous, diffuse cutaneous, mucocutaneous) and severity of disease is a function of the infecting Leishmania species together with host genetics and consequent inflammatory and immune responses. It has become evident from genetic and immunological studies using the murine model that the various members of the genus Leishmania differ in aspects of their 'approach' to the host immune system. We are just beginning to appreciate the complexities of these interactions, which have import for the development of a vaccine against leishmaniasis. In this paper, what is currently understood concerning the mechanisms of leishmanial pathogenesis (based upon studies employing the murine model) is briefly summarized.

Essential role of platelet-activating factor in control of Leishmania (Leishmania) amazonensis infection

In the present study we investigated the role of platelet-activating factor (PAF) and prostaglandins in experimental Leishmania (Leishmania) amazonensis infection and the relationship between these mediators and nitric oxide (NO) production. Mouse peritoneal macrophages elicited with thioglicolate were infected with leishmania amastigotes, and the infection index determined 48 h later. The course of infection was monitored for 5 weeks in mice infected in the footpad with promastigotes by measuring the footpad swelling and parasite load in regional lymph nodes and spleen. The addition of PAF to C57BL/6 mouse macrophages significantly inhibited parasite growth and induced NO production. Treatment of macrophages with a selective PAF antagonist, WEB2086, increased the infection, indicating that endogenously produced PAF regulates macrophage ability to control leishmania infection. This effect of PAF was abolished by addition of the inhibitor of NO synthesis, L-NAME, to the cultures. The addition of prostaglandin E(2) significantly increased the infection and NO production. Treatment with cyclo-oxygenase inhibitor, indomethacin, reduced the infection and PAF-induced release of NO. Thus, the increased NO production induced by PAF seems to be mediated by prostaglandins. The more-selective inhibitors of cyclo-oxygenase 2, nimesulide and NS-398, had no significant effect. Thus, antileishmanial activity correlates better with the presence of PAF or absence of prostaglandins than with NO production. In vivo treatment with PAF antagonists significantly increased leishmania lesions, as well as the parasite load, in regional lymph nodes and spleens. These findings indicate that PAF is essential for the control of leishmania infection.

Cytologic diagnosis of leishmaniasis in HIV infection. A report of eight cases

BACKGROUND

Leishmania organisms are among the intracellular microorganisms with a tendency to develop in patients with the acquired immunodeficiency syndrome (AIDS). With increasing travel to endemic areas by patients with human immunodeficiency virus (HIV) infection, it is becoming a more-frequent diagnosis in nonendemic areas.

CASES

Ten cytologic specimens from eight patients with leishmaniasis and AIDS were reviewed. Eight samples were obtained from lymph nodes through fine needle aspiration (FNA). Another sample was obtained after scraping a tongue ulcer. The last one was an ascitic fluid specimen. Smears showed numerous parasitized histiocytes with abundant intracellular Leishmania organisms (amastigotes). Extracellular microorganisms were also abundant. Diff-Quik-stained smears allowed the clear recognition of the characteristic morphologic appearance with a deep-staining area (nuclei) and paranuclear zone (kinetoplast). Intracellular organisms were round, while single, extracellular forms were a more elongated.

CONCLUSION

The polymorphous clinical manifestations usually seen in patients suffering from leishmaniasis and AIDS constitute a diagnostic challenge that can be facilitated by cytopathologic examination. Cytology permits easy and rapid identification of Leishmania amastigotes, allowing a specific diagnosis and treatment.

Leishmania major infections in Phlebotomus duboscqi fed on murine models immunized with L. major subcellular antigens and sandfly gut antigens

The ability of antibodies in bloodmeals of mice and hamsters immunized with Leishmania major subcellular fractions and sandfly (Phlebotomus duboscqi) gut antigens to inhibit development of L. major in its vector P. duboscqi was examined. Antibodies from animals immunized with either L. major subcellular fractions alone or sandfly gut antigen alone were not very effective in inhibiting development of L. major in the sandfly. When P. duboscqi were fed on blood from animals immunized with both parasite flagella and sandfly gut antigen, development of L. major was significantly inhibited (P<0,05). Control sandflies fed on naive animals displayed a normal pattern of parasite development to the metacyclic stage. Electron microscopy studies showed that one of the mechanisms through which antisandfly gut antibody can cause inhibition of parasite development is by lysing sandfly gut epithelium. This study has demonstrated that it is possible to reduce transmission of leishmaniosis through immunization against both the parasite and its sandfly vector.

Leishmaniasis in the United States military

Leishmaniasis is a recurrent health problem for the U.S. and other militaries. Health care workers may be unfamiliar with the risk factors, transmission, clinical features, diagnosis, and treatment of this disease. A team of highly trained specialists is required to properly manage service members with leishmaniasis. Such care is available only in a few medical centers. Although there are no prophylactic drugs to prevent this disease, control of insect populations and use of personal protection measures can minimize arthropod-related casualties. The impact of leishmaniasis on military operations and research initiatives to better prevent, diagnose, and treat infection are discussed.

Practical guide for the treatment of leishmaniasis

This article summarises the clinical features of visceral, cutaneous and mucocutaneous leishmaniasis, and leishmaniasis in HIV-coinfected patients. The characteristics and clinical use of pentavalent antimonials and the traditional drugs used in all forms of leishmaniasis are described. There have been important developments in therapy, such as aminosidine (paromomycin) conventional amphotericin B and lipid-associated amphotericin B. In most cases of leishmaniasis there is a range of treatment options which is determined by the geographical and clinical features. This review is intended to assist the clinician in choosing treatment and in using unfamiliar drugs with safety and efficacy.

The effect of intravenous or subcutaneous administration of meglumine antimonate (Glucantime) in dogs with leishmaniasis. A randomized clinical trial

The efficacy of i.v. versus s.c. administration of Glucantime (100 mg/kg of body weight/day) was studied in 41 dogs with leishmaniasis without serious renal insufficiency. Remission was obtained in 35 dogs (85.4%) after 3 to 6 weeks of treatment but there was a relapse within 1 year in 26 dogs (74.3%). The median period of remission was 6 months. Cross-over therapy resulted in remission in 17 of 20 dogs. The percentage of remission after initial and cross-over therapy, the median relapse free period, and survival did not differ significantly between the two groups. There were very few complications and most were of minor clinical importance. Thrombophlebitis developed in one dog after i.v. injection. In dogs with leishmaniasis without serious renal insufficiency, there is a 75% probability of survival for more than 4 years following treatment with Glucantime for 3 to 6 weeks, with additional treatment when relapses occur.

Up-regulation of T helper 2 and down-regulation of T helper 1 cytokines during murine retrovirus-induced immunodeficiency syndrome enhances susceptibility of a resistant mouse strain to Leishmania amazonensis

Resistance to and recovery from leishmania infection is dependent on cell-mediated immunity. C57BL/6 mice are resistant to Leishmania amazonensis (La) infection but susceptible to LP-BM5 murine leukemia virus (MuLV) infection. MuLV infection leads to a state of immunodeficiency characterized by severe compromise of cell-mediated immunity. When infected with La alone, C57BL/6 mice developed a small transient lesion that evolved to spontaneous healing or a lesion with extremely slow growth. Lesions were predominantly comprised of a lympho-macrophagic infiltrate with few parasitized macrophages. When infected with La and, 4 weeks later, with MuLV (La-MuLV), the mice developed a large uncontrolled nonhealing lesion containing vacuolated and heavily parasitized macrophages. In contrast, mice infected with MuLV first and La 4 weeks later (MuLV-La) developed a small but persistent lesion, characterized histologically by a small number of heavily parasitized macrophages and few lymphocytes. Eight weeks after MuLV infection, both had similar immunological profiles with decreased lymphocyte proliferation, diminished production of interferon-gamma, and high production of interleukins 4 and 10. At the time of L. amazonensis infection, La-MuLV animals have a normal T cell function whereas in MuLV-La mice this function is already impaired; this may influence the recruitment of macrophages to the site of leishmania injection.

Dermatologic manifestations of infectious diseases in cardiac transplant patients

Infection remains a significant cause of morbidity and mortality in cardiac transplant patients. Skin infections are not uncommon in these patients. Although usually caused by secondary dissemination after initial infection of another organ system, some skin infections may be primary infections, such as bacterial infections caused by the use of intravenous catheters or fungal infections in severely immunosuppressed patients. Nevertheless, the presence of skin lesions in a transplant patient may indicate infection in a primary site or another deep-seated focus of infection.

Recognition of the major cell surface glycoconjugates of Leishmania parasites by the human serum mannan-binding protein

Activation of complement on the surface of parasitic protozoa of the genus Leishmania appears to be important for parasite infectivity in the mammalian host, as it allows these parasites to attach to and invade macrophages via their surface complement receptors. Serum mannan-binding protein (MBP) is a known activator of complement. Therefore, in the present study, we have investigated whether serum MBP binds to live Leishmania parasites, and to mannose-containing saccharides derived from the parasite cell surface. We have observed by fluorescence microscopy that biotinylated MBP binds to the surface of L. major and L. mexicana promastigotes. At this developmental stage the parasites are coated by a mannose-containing lipophosphoglycan (LPG). We have observed that radioiodinated MBP binds in a mannose-inhibitable manner to purified LPG which has been immobilized in plastic microwells, as well as to purified mannose-terminating di-, tri- and tetrasaccharide fragments ('cap' structures) which have been released by mild acid hydrolysis from the outer chains of the LPG, converted into neoglycolipids and resolved by thin-layer chromatography. 125I-MBP also binds in the chromatogram-binding assay to the mannose-containing glycoinositol-phospholipids that are expressed in high copy number on both the promastigote and the intracellular amastigote stages of most Leishmania species. These data suggest that MBP has the potential to opsonize the major developmental stages of Leishmania parasites, and provide a possible mechanism for the antibody-independent activation of complement on their surface.

Cytokine patterns in the pathogenesis of human leishmaniasis

The host response to infection appears to be regulated by specific patterns of local cytokine production. In the mouse, resistance to many pathogens including Leishmania is associated with a TH1 cytokine profile, IL-2 and IFN-gamma; whereas susceptibility to infection is associated with production of TH2 cytokines, IL-4, IL-5, and IL-10. To determine the cytokine patterns of the local immune response to Leishmania infection in humans, we used the polymerase chain reaction to compare cytokine mRNAs in biopsy specimens of American cutaneous leishmaniasis. In localized cutaneous leishmaniasis and the Montenegro delayed-type hypersensitivity reaction, type 1 cytokine mRNAs such as IL-2, IFN-gamma, and lymphotoxin were relatively predominant. In the chronic and destructive mucocutaneous form of leishmaniasis, there was a mixture of type 1 and type 2 cytokines, with a striking abundance of IL-4 mRNA in lesions. These results suggest that clinical course of infection with Leishmania braziliensis in man is associated with specific local patterns of cytokine production.

Laboratory-acquired malaria, leishmaniasis, trypanosomiasis, and toxoplasmosis

Because of renewed interest in parasitic diseases, increasing numbers of persons in clinical and research laboratories have the potential for exposure to parasites and therefore are at risk for acquiring parasitic infections. In this review of laboratory-acquired parasitic infections, we concentrate on protozoan diseases that frequently have been reported to be laboratory acquired: malaria, leishmaniasis, trypanosomiasis (American and African), and toxoplasmosis. These diseases can be severe, even fatal, and may be difficult to diagnose. Many laboratorians who have acquired these diseases did not recall having had an accident. Of those with recognized accidents, needlestick injuries were the most common. Laboratories should have established protocols for handling specimens that may contain viable organisms and for responding to laboratory accidents.

Analysis of enhancing effect of sand fly saliva on Leishmania infection in mice

Salivary gland lysates of the sand fly Lutzomyia longipalpis markedly enhance the course of infection with Leishmania major in mice. Here we examine various parameters of this phenomenon. The exacerbative effect of L. longipalpis salivary gland lysates occurred in five different mouse strains; however, the character of the effect varied from one strain to another. Consistent exacerbation of infection was achieved with as little as 1/10 of a gland. The exacerbative effect applied to more than one Leishmania species and to more than one species of sand fly, since salivary gland lysates of L. longipalpis enhanced infection with L. mexicana amazonensis and salivary gland lysates of Phlebotomus papatasi enhanced infection with L. major. A synthetic rat calcitonin gene-related peptide was also found to exacerbate infection with L. major but was found to be approximately 100-fold less potent than saliva in mediating this effect. In addition, lesions induced at skin sites at which L. longipalpis had probed for a blood meal exhibited an exacerbated course of infection similar to that seen when parasites were injected with sand fly salivary gland lysates.

[Popular conceptions regarding cutaneous leishmaniasis in Colombia and their applicability in control programs]

A study was carried out to obtain information on prevailing popular ideas and attitudes about cutaneous leishmaniasis and its treatment in an isolated endemic area on the Colombian Pacific Coast. Interviews were conducted with a representative sample of individuals from the community and with health agents. The formal survey covered 736 households, 332 of them in a rural area (where leishmaniasis is endemic) and 404 in the city of Buenaventura (where there is no transmission of the disease.) The results showed that cutaneous leishmaniasis is well known in the rural area. The people have names for it (ya-te-vi or bejuco), have an understanding of its etiology (although their interpretation differs from that accepted by the scientific community), and have developed methods for preventing and treating it. The popular understanding of the disease results in behavior directed toward its prophylaxis and treatment that shares many characteristics with Western medicinal practices. The traditional treatments should be taken into account in the application of measures to control the disease in that area.

Leishmania donovani chagasi: new clinical variant of cutaneous leishmaniasis in Honduras

During surveillance for endemic visceral leishmaniasis on an island off the Pacific coast of Honduras, an unusual form of cutaneous leishmaniasis was encountered. By clinical and laboratory criteria, 17 cases were identified over 5 months; children aged 4 to 15 years were primarily affected. Lesions were generally few in number, small, always papular, and non-ulcerative, even when present for several years. Patients with skin lesions seemed otherwise healthy and were well nourished. Montenegro skin tests with Leishmania mexicana and L major antigens were positive in 10 of 17 patients tested, and lesions from 9 patients were positive by culture. Since the summer of 1988, cases of atypical cutaneous leishmaniasis continue to occur on the island (8) as well as on the mainland of southern Honduras (23). A total of 9 parasite isolates from skin lesions, 4 from bone marrow of patients with kala-azar, and 2 from sandflies were identified as L donovani chagasi and were indistinguishable from one another by isoenzyme analysis.

The pathogenesis of Leishmania aethiopica infection in BALB/c mice

A mouse model for L. aethiopica infection is described. BALB/c mice were unable to clear an infection with 1 x 10(7) promastigotes injected into the hind footpad. However, there was no ulceration of the lesion and no development of overt clinical symptoms after 203 days of infection. Spread of viable organisms was evident in the draining lymph node but not in the spleen or liver. The control of the infection was associated with the development of classical delayed hypersensitivity responses to phenolized promastigotes and appeared as a localized granulomtaous infiltration. The infiltration had features of classical tuberculoid granulomas, but superimposed on it was a strong eosinophilic infiltration. The relevance of such cells though unclear is discussed.

Efficacy of prolonged therapy with stibogluconate in post kala-azar dermal leishmaniasis

Fifty three (30 male and 23 female), previously untreated, patients with post kala-azar dermal leishmaniasis (PKDL) were treated with sodium stibogluconate, at the dose of 20 mg/kg/bw/d/im/(with a maximum of 8.5 ml) for 120 days (or more, if necessary). All the patients were followed up for 12 months. The patients were assessed after 40 days and thereafter at an interval of 20 days. The mean age of onset was 24 yr, maximum number of patients developed the disease within 3 yr of apparent cure of kala-azar. Maximum number of patients sought treatment within 5 yr of the onset of PKDL. The disease affected the face (98%), trunk (83%), upper limb (72%), lower limb (40%), genetalia (6%), and mucus membrane of the tongue 40%. The lesions observed were nodules (19%), papules (30%), and hypopigmented (45%) and reddish macules (7%). The parasites could be demonstrated in the nodules (100%), papules (69%) and macules (59%). The response to treatment started in 72 per cent of patients in the first 20 days and in 40 days in all patients. All the nodules and papules disappeared in 120 days, and the macules within 200 days. The side effects of treatment noted were changes in S T and T in electrocardiogram (7%), arthralgia (11%), allergic rash (7%), swelling at the site of injection (5%), neuralgia (4%) and metalic taste (6%). The S T and T changes reverted to normal when the drug was discontinued for 20 days. Arthralgia improved with indomethacin. The higher dosages and longer course of treatment were well tolerated and resulted in a cure in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[An outbreak of cutaneous leishmaniasis caused by Leishmania infantum in Geokchaĭ District, Azerbaijan SSR]

A more than 60-case outbreak of cutaneous leishmaniasis was documented in the Geokchaĭ District of Azerbaijan between 1987 and 1988. The disease was noted in the rural areas only. All age groups were involved. The clinical picture of the disease was significantly different from anthropogenic cutaneous leishmaniasis caused by L. tropica but similar to cutaneous patterns caused by L. infantum which was a prevalent pattern in the southern France. Isoenzyme assay of the strain isolated in the Geokchaĭ causative agent defined it as Leishmania donovani sensu lato. Though an undoubted similarity of its enzymatic profile to L. infantum was observed it was distinguished as a singular zymodeme. A total of 9 Phlebotominae species were isolated in the Geokchaĭ District. Among them 5 species (P. kandelakii, P. tobbi, P. transcaucasicus, P. brevis, P. alexandri) were reviewed in the literature with regard to L. infantum transmission. Thus cutaneous leishmaniasis caused by L. infantum species in the rural area of the USSR was identified for the first time.

Excreted factors and membrane-associated carbohydrates of Indian leishmaniae

Antigenic identity between the cell surface carbohydrate ligands and their excreted factor (EF) in all forms of Indian leishmaniasis were assessed by 11 carbohydrate-specific lectins. Our results demonstrated that 3 lectins, viz. PNA, SBA and WFA showed unique selectivity towards skin-dwelling parasites. The EFs of visceral leishmaniasis (VL), post-kala-azar dermal leishmaniasis (PKDL) and cutaneous leishmaniasis (CL) formed band against ConA at 1000, and 500 micrograms/ml concentration, respectively. RCA-120 at 3 mg/ml concentration was positive to both Leishmania tropica and L. major, whereas SBA was specific to L. tropica, L. major and PKDL strains at the same concentration. Antisera directed against the EFs (EF-As) induced agglutination to homologous promastigotes suspension. Cross-reactivity of agglutination was observed in different strains but highest was found among PKDL and CL strains. Although PKDL cases are normally found in patients with the history of visceral leishmaniasis (kala-azar), surprisingly in this study, the surface saccharides of PKDL strains had close affinity to CL type instead of VL.