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Showing papers on "Visceral leishmaniasis published in 2000"


Journal ArticleDOI
TL;DR: In India, 320 patients with visceral leishmaniasis received identical pentavalent antimony (Sb) treatment, and Sb induced long-term cure in 35% of those in Bihar versus 86% (95% CI, 79%-93%) of Those in Uttar Pradesh.
Abstract: In India, 320 patients with visceral leishmaniasis (209 in the state of Bihar and 11 in the neighboring state of Uttar Pradesh) received identical pentavalent antimony (Sb) treatment. Sb induced long-term cure in 35% (95% confidence interval [CI], 28%-42%) of those in Bihar versus 86% (95% CI, 79%-93%) of those in Uttar Pradesh. In Bihar, the center of the Indian epidemic, traditional Sb treatment should be abandoned.

606 citations


Journal ArticleDOI
TL;DR: It was found no evidence that two doses of ALM plus BCG offered significant protective immunity against visceral leishmaniasis compared with BCG alone, andLeishmanin skin conversion with an induration of 5 mm or more in either group was associated with protection from the disease.

225 citations


Journal ArticleDOI
TL;DR: The burden of disease caused by leishmaniasis is addressed, focusing on both incidence rates and on the variability in symptoms, and the variation in transmission ecology is described, outlining those variables which might affect the prevention strategies.
Abstract: This paper reviews the current knowledge of leishmaniasis epidemiology in Venezuela, Colombia, Ecuador, Peru, and Bolivia. In all 5 countries leishmaniasis is endemic in both the Andean highlands and the Amazon basin. The sandfly vectors belong to subgenera Helcocyrtomyia, Nyssomiya, Lutzomyia, and Psychodopygus, and the Verrucarum group. Most human infections are caused by Leishmania in the Viannia subgenus. Human Leishmania infections cause cutaneous lesions, with a minority of L. (Viannia) infections leading to mucocutaneous leishmaniasis. Visceral leishmaniasis and diffuse cutaneous leishmaniasis are both rare. In each country a significant proportion of Leishmania transmission is in or around houses, often close to coffee or cacao plantations. Reservoir hosts for domestic transmission cycles are uncertain. The paper first addresses the burden of disease caused by leishmaniasis, focusing on both incidence rates and on the variability in symptoms. Such information should provide a rational basis for prioritizing control resources, and for selecting therapy regimes. Secondly, we describe the variation in transmission ecology, outlining those variables which might affect the prevention strategies. Finally, we look at the current control strategies and review the recent studies on control.

200 citations


Journal ArticleDOI
TL;DR: This study has identified a novel vaccine candidate Ag for visceral leishmaniasis, which appears to operate via a mechanism similar to that previously associated with DNA vaccination.
Abstract: Vaccination against visceral leishmaniasis has received limited attention compared with cutaneous leishmaniasis, although the need for an effective vaccine against visceral leishmaniasis is pressing. In this study, we demonstrate for the first time that a recombinant stage-specific hydrophilic surface protein of Leishmania donovani, recombinant hydrophilic acylated surface protein B1 (HASPB1), is able to confer protection against experimental challenge. Protection induced by rHASPB1 does not require adjuvant and, unlike soluble Leishmania Ag + IL-12, extends to the control of parasite burden in the spleen, an organ in which parasites usually persist and are refractory to a broad range of immunological and chemotherapeutic interventions. Both immunohistochemistry (for IL-12p40) and enzyme-linked immunospot assay (for IL-12p70) indicate that immunization with rHASPB1 results in IL-12 production by dendritic cells, although an analysis of Ab isotype responses to rHASPB1 suggests that this response is not sufficient in magnitude to induce a polarized Th1 response. Although both vaccinated and control-infected mice have equivalent frequencies of rHASPB1-specific CD4(+) T cells producing IFN-gamma, vaccine-induced protection correlates with the presence of rHASPB1-specific, IFN-gamma-producing CD8(+) T cells. Thus, we have identified a novel vaccine candidate Ag for visceral leishmaniasis, which appears to operate via a mechanism similar to that previously associated with DNA vaccination.

198 citations


Journal ArticleDOI
TL;DR: A highly sensitive PCR method that enables the diagnosis and posttherapeutic follow-up of visceral leishmaniasis with patient blood and is sufficient to provide a secure diagnosis for all immunocompromised patients and most Immunocompetent patients is developed.
Abstract: We developed a highly sensitive PCR method that enables the diagnosis and posttherapeutic follow-up of visceral leishmaniasis with patient blood. The PCR assay was thoroughly optimized by successive procedural refinements to increase its sensitivity and specificity. It was compared to in vitro cultivation as well as to direct examination of bone marrow and to serology. Two hundred thirty-seven patients presenting with clinical signs compatible with visceral leishmaniasis were included in the study. Thirty-six were diagnosed as having Mediterranean visceral leishmaniasis (MVL). Twenty-three of them, including 19 AIDS patients, were monitored during and after treatment over a period from 2 weeks to 3 years. Our PCR assay proved more sensitive than in vitro cultivation, direct examination, and serology for all patients. It is simple and can be adapted to routine hospital diagnostic procedures. For the primary diagnosis of MVL, the sensitivity of PCR versus that of cultivation was 97 versus 55% with peripheral blood and 100 versus 81% with bone marrow samples. Regarding posttherapeutic follow-up, overall, 48% of positive samples were detected by PCR only. Seven patients presented with a clinical relapse during the study; six relapses were detected at first by PCR only, sometimes a few weeks before the reappearance of signs or symptoms. We conclude that an optimized and well-mastered PCR assay with a peripheral blood sample is sufficient to provide a secure diagnosis for all immunocompromised patients and most immunocompetent patients. We also suggest systematic posttherapeutic monitoring by PCR with peripheral blood for immunocompromised patients.

161 citations


Journal ArticleDOI
TL;DR: A total of 54 Indian patients with visceral leishmaniasis were treated with oral miltefosine, 50 mg given twice daily, for 14 days, 21 days, or 28 days, and cure was achieved in 89% of groups A, 100% of group B, and 100%" of group C.
Abstract: A total of 54 Indian patients with visceral leishmaniasis were treated with oral miltefosine, 50 mg given twice daily, for 14 days (18 patients; group A), 21 days (18; group B), or 28 days (18; group C). Cure was achieved in 89% of group A, 100% of group B, and 100% of group C. Adverse reactions were self-limited and primarily mild. The 21-day miltefosine regimen combines high-level efficacy, convenient dosing, and a relatively short duration.

139 citations


Journal ArticleDOI
TL;DR: The wider use of the rK39 dipstick test could improve the specificity of VL diagnosis in Nepal, and has the advantages of ease of use and obtaining results within minutes.
Abstract: We evaluated the field use of two serologic tests for visceral leishmaniasis (VL), the direct agglutination test (DAT) and rK39 dipstick test, in the context of a case-control study. Most VL cases in Nepal are currently diagnosed on clinical grounds and with relatively non-specific tests such as the formol-gel test. Among 14 newly diagnosed VL patients with bone-marrow slides confirmed positive in two independent laboratories, the sensitivity of both tests was 100%. Among 113 controls with no personal or household history of VL, the specificity of the rK39 was 100% while that of the DAT was 93%. The rK39 was less expensive than DAT, and has the advantages of ease of use and obtaining results within minutes. The wider use of the rK39 dipstick test could improve the specificity of VL diagnosis in Nepal.

136 citations


Journal ArticleDOI
TL;DR: The data suggest that the clinical manifestations of VL may be influenced by the immunological status, with atypical locations of Leishmania amastigotes more frequently found in severely immunocompromised patients.
Abstract: A retrospective study was conducted in France in 1998 to determine the clinical features of visceral leishmaniasis (VL) in 91 patients infected cocomitantly with human immunodeficiency virus. Our data suggest that the clinical manifestations of VL may be influenced by the immunological status, with atypical locations of Leishmania amastigotes more frequently found in severely immunocompromised patients. In such patients, the involvement of atypical locations may lead to the discovery of VL.

125 citations


Journal ArticleDOI
TL;DR: Although research needs on vaccine and better drugs continue to be high on the agenda, a VL test-treatment strategy based on currently available highly sensitive serological tests, such as the DAT, should be introduced in the health services in endemic areas.
Abstract: Visceral leishmaniasis (VL), also known as kala-azar, is a vector-borne disease caused by a protozoan of the Leishmania donovani complex. A phlebotomine sandfly transmits the parasite from person to person or via an animal reservoir. VL is a severe, debilitating disease, characterized by prolonged fever, splenomegaly, hypergammaglobulinaemia and pancytopenia. Patients become gradually ill over a period of a few months, and nearly always die if untreated. Case-fatality ratios are high even in treated patients. Worldwide an estimated 500 000 VL cases occur each year. This study reviews clinical, epidemiological and public health aspects of the disease and shows how critical adequate case detection is for the success of VL control. Examination of the issue of VL diagnosis with respect to the global challenges in VL control leads to the observation that a sound diagnostic-therapeutic algorithm for the health services in endemic areas is badly needed. Serological tests could be an alternative to parasitological diagnosis and the direct agglutination test (DAT) was found to fulfil many criteria for a ‘field test’, including cost effectiveness. Although research needs on vaccine and better drugs continue to be high on the agenda, a VL test-treatment strategy based on currently available highly sensitive serological tests, such as the DAT, should be introduced in the health services in endemic areas.

115 citations



Journal ArticleDOI
TL;DR: It is demonstrated that IL‐4 has an important role in effective anti‐leishmanial chemotherapy which seems to be related to modulation of IFN‐γ production.
Abstract: It is well established that a fully competent immune response is required for the successful drug treatment of visceral leishmaniasis. However, recent studies have cast some doubt as to which elements of the immune response synergize with chemotherapeutic treatment. The role of the Th2 response and IL-4 in particular during visceral leishmaniasis awaits clarification. We, therefore, examined the effectiveness of sodium stibogluconate treatment on Leishmania donovani infection in BALB/c wild-type and IL-4-/- mice. Parasite burdens in L. donovani-infected IL-4+/- and IL-4-/-, as we have previously shown for B6/129 mice, were similar, despite an apparent type 1 antibody response in infected IL-4-/- mice, demonstrated by increased levels of parasite-specific IgG2a and decreased IgG1. Unexpectedly IL-4-/- mice responded poorly to sodium stibogluconate treatment with increased parasite burdens in all tissues examined. Furthermore, drug therapy of IL-4-/- but not IL-4+/+ mice resulted in significant reductions in splenocyte IFN-gamma mRNA transcripts and in serum IFN-gamma levels. These results demonstrate that IL-4 has an important role in effective anti-leishmanial chemotherapy which seems to be related to modulation of IFN-gamma production.

Journal ArticleDOI
TL;DR: A diagnosis of VL should be seriously considered in all young patients with HS exposed to visceralizing Leishmania sp in Southern Europe and Clinicians and cytopathologists must be aware of the association.
Abstract: Objective. To describe the difficulties in diagnosing visceral leishmaniasis (VL) when revealed by hemophagocytic syndrome (HS) in young children. Design. Retrospective study of patients identified over a 17-year period in French pediatric units. Results. This series comprises 12 cases of VL that were either revealed ( n = 11) or complicated (on starting treatment with antimony salts [ n = 1]) by HS. Clinical manifestations were those of severe VL with sustained high fever and hepatosplenomegaly in children in very poor condition. Biological manifestations always included pancytopenia, marked hypofibrinogenemia and hypertriglyceridemia, hepatic cytolysis, and prominent hemophagocytosis on the bone marrow smear. These features led to transfer to a hematology unit. Ten children were very young ( Leishmania were negative at onset in 6 children, and no amastigotes were found on the first marrow smear in 8 of 12 cases despite extensive search. Seven patients had not visited foreign countries. All these factors explain the initial diagnostic confusion. Three cases were initially misdiagnosed as familial erythrophagocytic lymphohistiocytosis or infection-associated HS, and these patients were treated with etoposide (once for 5 months) to control the HS after failure of steroids. The diagnostic delay in these cases was 50, 74, and 134 days. When VL was finally diagnosed, amphotericin B monotherapy was effective in 4 cases. Eight patients were treated with antimony salts; 4 were cured, 3 required adjunctive treatment, and 1 worsened (HS) and was cured with steroids and liposomal amphotericin. Regardless of the type of therapy, all 12 children are presumed cured with a mean follow-up of 7 years (range: 6 months–16 years). Conclusions. A diagnosis of VL should, therefore, be seriously considered in all young patients with HS exposed to visceralizing Leishmania sp in Southern Europe. Clinicians and cytopathologists must be aware of the association. Early diagnosis of VL will minimize unnecessary hospitalization and potentially harmful investigations and treatments.

Journal ArticleDOI
TL;DR: This report reviews the evolution of treatment of visceral leishmaniasis, considers the interaction of the immune response and chemotherapy, highlights therapeutic successes and failures, examines advantages and disadvantages of current treatments, and looks at future therapeutic approaches to the management of this disseminated intracellular protozoal infection.

Journal ArticleDOI
TL;DR: The comparatively low prevalence of Leishmania (Viannia) in the blood of symptomatic dogs indicates that PCR with blood cannot be the “gold standard” for the (mass) screening of samples in epidemiological studies.
Abstract: A PCR-based protocol for the detection of Leishmania ( Viannia ) parasites in canine blood, buffy coat, and bone marrow was developed and was then tested with field samples taken from a random sample of 545 dogs from villages in Peru where Leishmania ( Viannia ) braziliensis and Leishmania ( Viannia ) peruviana are endemic. Comparative tests with cultured parasites mixed with dog blood showed that the PCR assay9s sensitivity was significantly dependent on the DNA extraction protocol and the PCR primers used. Mass screening of field samples by the preferred PCR protocol detected American cutaneous leishmaniasis (ACL) in 44 of 545 (8.1%) dogs; 31 of 402 (7.7%), 20 of 223 (9.0%), and 8 of 46 (17.4%) were PCR positive when whole blood, buffy coat, and bone marrow aspirates, respectively, were tested. The high prevalence of Leishmania in both asymptomatic (7.6%) and symptomatic (18.0%) dogs provides further circumstantial evidence for their suspected role as reservoir hosts of ACL and indicates that hematogenous dissemination of parasites may be a more common pathological phenomenon than has previously been acknowledged. However, unlike for zoonotic visceral leishmaniasis, the comparatively low prevalence of Leishmania ( Viannia ) in the blood of symptomatic dogs indicates that PCR with blood cannot be the “gold standard” for the (mass) screening of samples in epidemiological studies.

Journal ArticleDOI
TL;DR: The failure of control programs for visceral leishmaniasis (VL) that depend on elimination of infected dogs suggests that other reservoir hosts may participate in the transmission cycle, and further experiments are necessary to evaluate the reservoir competence of persons with asymptomatic infections.
Abstract: The failure of control programs for visceral leishmaniasis (VL) that depend on elimination of infected dogs suggests that other reservoir hosts may participate in the transmission cycle. To determine whether persons infected with Leishmania chagasi can infect the vector sand fly, laboratory-reared Lutzomyia longipalpis were allowed to feed on Brazilian subjects with active, cured, and asymptomatic VL and on asymptomatic residents of houses of persons with active VL. Of 3747 insects that had fed, 26 acquired infection from 11 of the 44 persons with active VL, but none acquired infection from the 137 asymptomatic persons. Among persons <4 years old with active VL, a history of diarrhea and higher peripheral blood neutrophil counts were independent predictors of infectivity. Further experiments using larger numbers of insects are necessary to evaluate the reservoir competence of persons with asymptomatic infections, who represent a large segment of the population of several Brazilian cities.

Journal ArticleDOI
TL;DR: In the absence of reliable and practical diagnostic tests, PKDL may be diagnosed on clinical grounds and differentiated from other conditions, of which miliaria rubra was the most common and differentiation from leprosy was most difficult.
Abstract: Post-kala-azar dermal leishmaniasis (PKDL) is a common complication following kala-azar (visceral leishmaniasis). In a prospective study in a village in the endemic area for kala-azar in the Sudan, 105 of 183 (57%) kala-azar patients developed PKDL. There was a significantly higher PKDL rate (69%) in those who received inadequate and irregular treatment of kala-azar than in those who were treated with stibogluconate 20 mg kg-1 daily for 15 days (35%). The group of patients who developed PKDL did not differ from those who did not develop PKDL with regard to age and sex distribution, reduction in spleen size, and conversion in the leishmanin skin test (LST). In a clinical study, 416 PKDL patients were analysed and divided according to grade of severity. Severe PKDL was more frequent in younger age groups (P < 0.001); there was an inverse correlation between grade and conversion in the LST (P < 0.01). In 16% of patients tested, parasites were demonstrated in inguinal lymph node or bone marrow aspirates, indicating still visceral disease (para-kala-azar dermal leishmaniasis); there was no correlation between the presence of parasites and grade of severity. Conversion rates in the LST were lower than in those who did not have demonstrable parasites (11% and 37%, respectively; P < 0.01). In the absence of reliable and practical diagnostic tests, PKDL may be diagnosed on clinical grounds and differentiated from other conditions, of which miliaria rubra was the most common. Differentiation from leprosy was most difficult.

Journal ArticleDOI
TL;DR: The data illustrate that the hamster is an excellent experimental model to study visceral leishmaniasis and for the design of vaccine development, and the existence of three groups of animals: symptomatic or susceptible, oligosymptomatic, and resistant.

Journal ArticleDOI
08 Dec 2000-Science
TL;DR: The widespread outbreak in dogs has experts wondering whether visceral leishmaniasis--which sickens over half a million people yearly in South America, Africa, the Mediterranean, and India--has become an endemic disease in North America.
Abstract: Believed to be all but absent from United States, the Leishmania parasite has infected more than 1000 hunting dogs in 21 U.S. states and the Canadian province of Ontario. Nobody is claiming that the disease is about to run riot among the U.S. population. But the widespread outbreak in dogs has experts wondering whether visceral leishmaniasis--which sickens over half a million people yearly in South America, Africa, the Mediterranean, and India--has become an endemic disease in North America.

Journal ArticleDOI
TL;DR: In countries where visceral leishmaniasis is endemic, particularly in southern Europe, immunosuppressive treatments for organ transplants or malignant diseases often result either in reactivation of asymptomatic visceral leishingmaniasis or in facilitation of new infections.
Abstract: Immunosuppression is associated with the occurrence of a large variety of infections, several of them due to opportunistic protozoa. The parasitic protozoa of the family Trypanosomatidae vary greatly in their importance as potential opportunistic pathogens. African trypanosomiasis is no more common nor severe during AIDS. The situation with Chagas' disease, however, is much different. Although the process is not clearly understood, there appears to be a reactivation of Trypanosoma cruzi infection, which can lead to severe meningoencephalitis. In persons with AIDS, leishmaniasis is often exacerbated, particularly Leishmania infantum, which causes visceral leishmaniasis in southern Europe. Since 1990, 1,616 cases of visceral leishmaniasis/HIV co-infection have been reported, mainly from southern Europe, and particularly from Spain, southern France, and Italy. The co-infected patients are primarily young adults and belong to the risk group of intravenous drug users. Isoenzymatic identification of 272 isolates showed 18 different L. infantum zymodemes, of which 10 represent new zymodemes hitherto found only during HIV co-infection. New foci of co-infection are emerging in various parts of the world, including Brazil and East Africa. Moreover, since 1995, non-human monoxenous trypanosomatids have been found in AIDS patients, causing both diffuse cutaneous lesions and visceral infections. In countries where visceral leishmaniasis is endemic, particularly in southern Europe, immunosuppressive treatments for organ transplants or malignant diseases often result either in reactivation of asymptomatic visceral leishmaniasis or in facilitation of new infections.

Journal ArticleDOI
TL;DR: The results point to the need for control of transmission of kala-azar by blood transfusion in areas endemic for this disease.
Abstract: Human visceral leishmaniasis (kala-azar) transmitted by blood transfusion has been described in previous reports. Seroprevalence of antibodies to Leishmania donovani was shown to be related to prior blood transfusions in multiply transfused hemodialysis patients in Natal, Rio Grande do Norte, Brazil. In this study, a possible correlation between seroreactivity and the presence of L. donovani DNA was investigated in asymptomatic healthy blood donors. Sera were tested using the fucose mannose ligand (FML) ELISA, which was shown to have a sensitivity of 100%, a specificity of 96-100%, reliability, and diagnostic and prognostic potential for the detection of human and canine kala-azar, respectively. Leishmanial DNA was assessed by the polymerase chain reaction (PCR) and dot-blot hybridization techniques in blood and bone marrow samples. Among 21 FML-seroreactive asymptomatic blood donors, 5 (24%) were positive by the PCR and 9 (43%) were positive in a dot-blot assay of blood samples, showing a significant correlation (chi2 = 14.24, P < 0.01). No Leishmania DNA was detected in 20 FML non-reactive blood donors. Our results point to the need for control of transmission of kala-azar by blood transfusion in areas endemic for this disease.

Journal ArticleDOI
30 Sep 2000-BMJ
TL;DR: The leishmania genome project as discussed by the authors was the first attempt to sequence part of each of the transcripts of all the genes of the organism, and the plan is now to sequence its entire genome.
Abstract: Leishmaniasis constitutes a diverse collection of human diseases ranging in severity from a spontaneously healing skin ulcer to overwhelming visceral disease. Worldwide, two million new cases occur each year, and a 10th of the world's population is at risk of infection.1 Although the disease is highly endemic throughout northern Africa, the Middle East, parts of Europe, and Central and South America, epidemics are well recognised. For example, in southern Sudan more than 10% of the population died from visceral leishmaniasis over the past five years. Outcome of infection is determined by interactions between the host and parasite, which are governed by the genomes of the host and parasite. It is therefore exciting to see that both host and parasite genomes have been targeted for sequence analysis.2 The leishmania genome project began as a large scale attempt to sequence part of each of the transcripts of all the genes of the organism, and the plan is now to sequence its entire genome. The genetic information from both human and parasite and the emergence of new tools such as microarray technologies will allow us to gain an understanding of the interaction between parasite virulence factors and host response factors. Molecular knowledge of the host-parasite interaction will facilitate targeting of new treatments. We chose topics for this article to convey the impact that current research will have on the pathophysiology and treatment of leishmaniasis. We used a variety of sources for the topics, including published original articles and reviews, the internet, and personal communications. ### Epidemiology Leishmaniasis results from an infection with the protozoan parasite Leishmania spp. The organism is transmitted to humans by the bite of the sandfly.1 Humans are usually accidental hosts of these 2 mm long flies; natural hosts include a variety of rodents, small mammals, and dogs. Disease …


Journal ArticleDOI
TL;DR: The results demonstrate that canine VL is wide spread in western Turkey where human Vl is endemic, and that serodiagnosis is a valuable tool for monitoring the infection.

Journal ArticleDOI
TL;DR: It is concluded that pentavalent antimonials remain the first choice of treatment for visceral leishmaniasis in immunocompetent children in areas where resistance has not become a problem and it is possible to treat affected patients with outpatient administration of these agents, making them feasible options for therapy.
Abstract: Records were reviewed of 82 immunocompetent children (median age, 2. 5 years) from southern Greece who were diagnosed with visceral leishmaniasis from 1986 through 1998. Forty-nine (58%) patients originated from the city of Athens; of them, 46 (94%) lived by hills bordering the city. The median interval from the onset of symptoms to admission was 10 days. Fever and splenomegaly were observed in >95% of the patients. Thrombocytopenia was the most frequent hematological finding (80%). All patients were treated with meglumine antimonate; 20 (24%) of them were partially treated on an outpatient basis. Rapid clinical response was noted in all patients but one. Five patients relapsed; 3 responded to reintroduction of meglumine antimonate, 1 responded to liposomal amphotericin B, and 1 underwent splenic artery ligation. We conclude that pentavalent antimonials remain the first choice of treatment for visceral leishmaniasis in immunocompetent children in areas where resistance has not become a problem. It is possible to treat affected patients with outpatient administration of these agents, making them feasible options for therapy.

Journal ArticleDOI
TL;DR: A 40‐year‐old human immunodeficiency virus (HIV)‐positive man had three relapses of visceral leishmaniasis (VL) and developed nodular skin lesions of three types, some reminiscent of Kaposi’s sarcoma.
Abstract: A 40-year-old human immunodeficiency virus (HIV)-positive man had three relapses of visceral leishmaniasis (VL). In the third he developed nodular skin lesions of three types, some reminiscent of Kaposi's sarcoma. Biopsy of each type disclosed abundant dermal macrophages with a huge number of intracellular and extracellular Leishman-Donovan bodies. Rapid improvement of lesions was achieved after antiparasitic treatment. AIDS leads to atypical forms of leishmaniasis. Leishmania has been detected both in normal and pathological skin of these patients due to dissemination during VL. It is suspected that a considerable proportion of the population may be infected in endemic areas, Leishmania being opportunistic in immunosuppressed individuals. It is important to recognize the range of lesions that may occur in patients with HIV and VL, many of which are non-specific and may cause diagnostic difficulty.

Journal ArticleDOI
TL;DR: The finding that PKDL develops after treatment of kala‐azar as Leishmania‐reactive T cells start to circulate in peripheral blood in sufficient numbers to be detected in in vitro assays supports the proposed immunological attack on parasites hypothesis.
Abstract: PKDL develops in about 50% of Sudanese patients treated for visceral leishmaniasis (kala-azar). Patients with kala-azar were entered into this study and followed for a period of up to 2 years. During follow up 12 patients developed PKDL and eight did not. Proliferative responses and cytokine production to Leishmania donovani and control antigens were measured in vitro using PBMC isolated at the time of diagnosis of kala-azar, after treatment of visceral leishmaniasis, during follow up, and at the time of diagnosis of PKDL. Proliferative responses and interferon-gamma (IFN-γ) production were low at diagnosis and increased after treatment of kala-azar in both patients who developed (group 1) and those who did not develop PKDL later (group 2). In group 1, development of PKDL was always associated by an increased PBMC response to Leishmania antigen in proliferation and IFN-γ production assays. There were no differences in Leishmania antigen-induced production of IL-4, IL-5 and IL-10 between or within the two groups. We have previously shown that Leishmania parasites spread to the skin during visceral leishmaniasis and proposed that PKDL was the result of an immunological attack on parasites, which have survived in the skin despite the drug treatment. The finding that PKDL develops after treatment of kala-azar as Leishmania-reactive T cells start to circulate in peripheral blood in sufficient numbers to be detected in in vitro assays supports this hypothesis.

Journal ArticleDOI
TL;DR: A case of post-kala-azar dermal leishmaniasis (PKDL) in a woman with AIDS which occurred 13 months after a diagnosis of visceral leish maniasis concomitantly with immunological recovery induced by highly active retroviral therapy is reported.

Journal ArticleDOI
TL;DR: The prevalence of antibodies against Leishmania donovani in selected domestic and wild animal species in 2 villages in Sudan and in humans was investigated, finding reaction rates above the cut-off titres in donkeys, cows, sheep, goats, camels and dogs.
Abstract: The prevalence of antibodies against Leishmania donovani in selected domestic and wild animal species in 2 villages in Sudan with active L. donovani transmission in humans was investigated. Screening of domestic animals (donkeys, cows, sheep, goats, camels and dogs) with the direct agglutination test (DAT) detected reaction rates above the cut-off titres in donkeys (68.7%), cows (21.4%) and goats (8.5%), and which were also found in wild rats (5.5%). Sera of sheep, camels and dogs had a weak agglutination reaction below the cut-off titre. Testing of the same sera by enzyme-linked immunosorbent assay (ELISA), against a lysate of L. donovani promastigotes, showed reaction rates above the cut-off optical density in cows (47.6%), goats (13.6%), and in rats (4.1%). No Leishmania parasite was isolated from spleen, liver, bone-marrow or spleen of Nile rats.

Journal ArticleDOI
TL;DR: The humoral response in patients coinfected with HIV and Leishmania is much lower than that in immunocompetent patients and that the immunoblot method is a sensitive, noninvasive, and specific serological technique for the diagnosis of visceral leishmaniasis in Immunocompromised patients is confirmed.
Abstract: This study evaluated the performance of immunoblotting with Leishmania infantum soluble antigens for the diagnosis of visceral leishmaniasis in human immunodeficiency virus (HIV)-infected and immunocompetent patients and assessed the humoral responses of patients coinfected with HIV and Leishmania. In this work, the results of the immunoblot analysis were compared to those of parasitological examination (Giemsa-stained smears and/or parasite isolation in Novy, Nicolle, and MacNeal medium from bone marrow) and indirect immunofluorescence and counterimmunoelectrophoresis techniques. Patients were considered to be infected if one or more of the comparison techniques gave a positive result. Immunoblotting was considered to be positive if at least one band was present. For 198 HIV-positive patients with a clinical suspicion of visceral leishmaniasis, immunoblot analysis had a sensitivity of 70.6%, a specificity of 73.2%, and an accuracy of 72.7%. For a separate group of 40 immunocompetent patients not infected with Leishmania, the immunoblot analysis was negative for all patients (100% specificity), and for a third group of 32 immunocompetent patients with confirmed visceral leishmaniasis, the immunoblot analysis was positive for all patients (100% sensitivity). Sera of coinfected patients recognized few bands and recognized bands at lower intensities compared with sera from immunocompetent patients. The most frequently detected band was 63 to 66 kDa (55.9%), with the difference being statistically significant compared to frequency of detection of the other bands. This study confirms that the humoral response in patients coinfected with HIV and Leishmania is much lower than that in immunocompetent patients and that the immunoblot method is a sensitive, noninvasive, and specific serological technique for the diagnosis of visceral leishmaniasis in immunocompromised patients.