Showing papers on "Visceral leishmaniasis published in 1992"

Kala-azar: a comparative study of parasitological methods and the direct agglutination test in diagnosis

Abstract: In a comparative study 88 patients were diagnosed as suffering from kala-azar (visceral leishmaniasis) using 3 parasitological methods simultaneously. Splenomegaly was absent in 4 cases. In 84 patients with splenomegaly, splenic aspiration appeared to be the most sensitive method (96.4%), followed by bone marrow aspiration (70.2%) and lymph node aspiration (58.3%). There was no relation between titres in the direct agglutination test and parasite load as determined by the number of parasitological methods which were positive or parasite density in splenic aspirates. Splenic aspiration and bone marrow aspiration were compared as an assessment of cure in kala-azar. In 6 (13%) of 46 patients tested, parasites were found, all by splenic aspiration. Bone marrow showed parasites in one of these. The literature with regard to parasitological investigations before and after treatment is reviewed.

Human leishmaniases: epidemiology and public health aspects.

Abstract: The leishmaniases are parasitic diseases caused by different species of Leishmania, protozoa transmitted by sandflies, haematophagous biting insects. The reservoir hosts are man (anthroponotic cycle) and domestic or wild animals (zoonotic cycle). In man the disease takes four main clinical forms: visceral, cutaneous, mucocutaneous and diffuse cutaneous. Morbidity and mortality due to leishmaniasis are on the increase. Leishmaniasis, which is now found on four continents, is endemic in 82 countries (21 in the New World and 61 in the Old). The large number of endemic countries shows the global scale of the problem, though it is particularly severe in certain countries (90% of cases of visceral leishmaniasis come from 4 countries). Annual incidence is estimated at some 600,000 new clinical cases, officially reported, with a global prevalence of 12 million cases and a population at risk of approximately 350 million. It is very difficult to provide realistic estimates given the frequency of subclinical forms of visceral leishmaniasis, the large number of undiagnosed or unreported cases, the frequent absence of active screening and the fact that the leishmaniases are notifiable diseases only in a few countries (30 out of 82); nevertheless, it seems clear that official reporting of cases considerably underestimates the problem. Over the last two decades, it has become clear that leishmaniasis is a growing public health problem in terms of geographical extent and incidence with the occasional severe epidemic, such as that which occurred in Sudan.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiology of visceral leishmaniasis in northeast Brazil.

Abstract: Epidemiologic aspects of the relationship between infection with Leishmania chagasi and development of clinical visceral leishmaniasis (VL) were studied in all children < 11 years old in a defined, endemic, rural area of the state of Ceara in northeast Brazil. Antileishmanial antibodies were measured in the same subjects by ELISA on six occasions between May 1987 and August 1989. Seroconversion was documented during this period in 108 children, with a cumulative annual incidence of 4.6%. Twelve (11.1%) of these children developed VL. Age < 4 years, hematocrit < 33%, and living in the mountains predicted the development of clinically apparent VL after seroconversion. Despite a high percentage of dogs serologically positive in the region (38%), there was no increased risk of infection for children living in the same household with dogs. Since children in households with a prior case of VL had a threefold increased risk of infection, human-sandfly-human transmission might have been important.

Hexadecylphosphocholine: oral treatment of visceral leishmaniasis in mice.

Abstract: Hexadecylphosphocholine (He-PC), a novel phospholipid derivative, was tested against Leishmania donovani and Leishmania infantum, the causative agents of visceral leishmaniasis. In vitro, promastigotes were highly susceptible to He-PC; the 50% inhibitory concentrations were between 0.89 and 2.25 micrograms/ml for the different leishmanial strains. In vivo, a marked antileishmanial activity in infected BALB/c mice could be demonstrated after oral administration of He-PC. Whereas parasite suppression and killing in the liver were comparable after 5 days of treatment with He-PC (10 or 20 mg/kg of body weight per day administered orally) and sodium stibogluconate (120 mg of pentavalent antimonal agent per kg/day administered subcutaneously), a superior reduction in the parasite load in the spleen and bone marrow was observed after oral treatment with He-PC. After a 4-week treatment period, parasite suppression in the spleen was better than that observed with standard sodium stibogluconate therapy by a factor of more than 600.

Immunologic Markers of Clinical Evolution in Children Recently Infected with Leishmania donovani chagasi

Abstract: The study attempted to identify immunologic markers for progression of Leishmania donovani chagasi infection to disease in children in an area endemic for visceral leishmaniasis (VL). [3H]thymidine uptake of lymphocytes stimulated with L. donovani chagasi antigen from children with asymptomatic infection (25,286 +/- 11,648) and from children with self-healing subclinical infection (15,511 +/- 4681) was greater (P = .001) than that observed with lymphocytes from children who progressed to classic VL (4811 +/- 2984). The interferon-gamma (IFN-gamma) levels from asymptomatic and subclinically infected children (74 +/- 90 units/ml) were higher (P = .02) than those observed in children who progressed to VL (7 +/- 8 units/ml). Absence of lymphocyte blastogenesis and IFN-gamma production were associated with progression of infection to classic VL. In the presence of these markers, children should be closely followed to identify signs and symptoms that would permit early initiation of therapy.

Western blot analysis of antibodies to Leishmania infantum antigens: potential of the 14-kD and 16-kD antigens for diagnosis and epidemiologic purposes.

Abstract: When infected with Leishmania species, patients develop specific antibodies that constitute the basis of serodiagnosis. Using Western blot analysis, we studied the specificity of anti-L. infantum antibodies in patients with visceral leishmaniasis (including patients with acquired immunodeficiency syndrome [AIDS]) and in healthy subjects living in an endemic area. Sera from patients with visceral leishmaniasis recognized numerous antigens that had a molecular mass range of 12-120 kD. The 14-, 16-, 28-30-, 46-, and 68-kD antigens were recognized by 92%, 95%, 63%, 80%, 69%, and 89% of the patients' sera, respectively. The 14-16-kD antigens had the greatest specificity for leishmaniasis. The same pattern was found with sera from AIDS patients with proven leishmaniasis, but the 14-kD band was not present in some cases; recognition of the 16-kD band was constant. In these patients, Western blotting characterized specific antibodies even when the results of classic serologic tests (indirect immunofluorescent antibody test and enzyme-linked immunosorbent assay) were negative. Western blotting was found to be more sensitive than the IFA and ELISA, and it was used to detect antibodies to the 14-, 16-, 22-, and 24-kD antigens in subjects living in an endemic area. The detection of antibodies for the 14-kD and 16-kD Leishmania antigens would be a valuable tool both in the diagnosis of visceral leishmaniasis and in epidemiologic studies.

Post kala-azar dermal leishmaniasis in the Sudan: clinical features, pathology and treatment.

Abstract: The clinical features, pathology, immune responses, diagnosis and treatment of post kala-azar dermal leishmaniasis (PKDL) in the Sudan are described and discussed. The disease is characterized by maculopapular or nodular lesions on the face, limbs or trunk. Lesions appear during or within months after the treatment of visceral leishmaniasis, but in 2 of 19 patients there was no previous history of kala-azar. PKDL may be confused with leprosy both clinically and pathologically. Similarities and differences between the 2 diseases are discussed. Unlike visceral leishmaniasis, the peripheral lymphoid cells of patients with PKDL respond to Leishmania antigen and some are leishmanin positive. The response to intravenous sodium stibogluconate (20 mg/kg for 30 d) was reasonably good but some patients required repeated or more prolonged treatment. Ketoconazole in a dose of 10 mg/kg daily for 4 weeks had no effect on PKDL.

Congenital kala-azar and leishmaniasis in the placenta.

Abstract: During an epidemic of visceral leishmaniasis in the Sudan, two cases of congenital kala-azar were seen The first child, whose mother had contracted kala-azar in southern Sudan, was born in Khartoum, where no transmission of leishmaniasis is currently occurring At seven months, the child had fever, lymphadenopathy, and hepatosplenom-egaly; leishmania parasites were detected in the bone marrow The child died and an autopsy showed leishmania parasites in all tissues including the lungs, kidneys, and thymus In the second case, parasites were found in the placenta of a five-month-old fetus These two cases demonstrate the importance of followup of infants born to mothers with leishmaniasis

Treatment of visceral leishmaniasis (kala-azar) with aminosidine (= paromomycin)-antimonial combinations, a pilot study in Bihar, India.

Abstract: A 20 d drug regimen of aminosidine (= paromomycin) at 12 mg/kg/d in combination with sodium stibogluconate at 20 mg/kg/d proved efficacious and well-tolerated in patients with visceral leishmaniasis in the State of Bihar, India. Eighteen of 22 evaluable patients achieved an ultimate cure. The remaining 4 patients, although not cleared of parasites, had their parasite grade reduced and also improved clinically. This confirms prior findings in Kenyan patients with kala-azar, and indicates that this regimen is a valid alternative to antimonial compounds alone in the State of Bihar, where cases of kala-azar not responding to antimonial drugs and intolerant of pentamidine are increasingly recorded.

Epidemic visceral leishmaniasis in southern Sudan : identity and systematic position of the parasites from patients and vectors

Abstract: Twenty-five strains of Leishmania donovani isolated from humans and Phlebotomus orientalis in an epidemic area of southern Sudan were shown to belong to 3 very similar zymodemes: MON 18 (11 strains), MON 30 (1 strain) and MON 82 (13 strains). The 3 zymodemes are very closely related and seem to behave as a single population.

Visceral leishmaniasis in HIV-1-infected individuals: a common opportunistic infection in Spain?

Abstract: Physicians examined the records of 47 adults with visceral leishmaniasis (VL) and HIV-1 infection who were patients at 3 urban teaching hospitals in the Andalucia region in southern Spain between January 1986 and November 1991. They wanted to identify the clinical biological and epidemiological features of VL in HIV-1 positive patients. 96% of the cases were diagnosed with both infections during the last 2 years of the study period and 79% between January and November 1991. All the patients had risk factors for HIV infection (65.9% IV drug use 21.3% sexual contact and 12.8% blood transfusion). 70% exhibited the classic symptoms of VL (fever enlarged liver and spleen and depressed counts of blood cells). Most patients were already very immunocompromised when VL was diagnosed. 87% had a total lymphocyte count of less than 1000 x 1 million/1 and a CD4 lymphocyte count of less than 200 x 1 million/1. In fact 66% had full blown AIDS prior to diagnosis of VL. VL was the first severe infection in 10 cases. 68% also suffered from opportunistic infections especially candidiasis extrapulmonary tuberculosis and Pneumocystis carinii pneumonia. Microscopic examination of Leishmania amastiogotes in tissue samples led to a diagnosis in 94% of cases isolation of motile amastigotes in culture of bone marrow aspirate in 2% and microscopic and culture in 4%. Just 46% completed a full course of treatment (pentavalent antimony allopurinol and/or pentamidine). Only 38% had a microbiological response. Immunofluorescence detected sizeable titers (>1:40) of antileishmanial antibodies in just 31% of cases. 17% experienced clear clinical improvement. Physicians in endemic areas should consider VL in every HIV-1 infected patient with fever hepatosplenomegaly or hematological abnormalities to avoid underdiagnosis of leishmaniasis.

HIV-Leishmania co-infections in Italy. Isoenzyme characterization of Leishmania causing visceral leishmaniasis in HIV patients

Abstract: Visceral leishmaniasis (VL) infections in patients with human immunodeficiency virus (HIV) infection are dramatically increasing in Mediterranean countries such as Spain, France and Italy. A study has been carried out to characterize biochemically the agents of typical or unusual VL in subjects with HIV infection and to compare results with those obtained so far from VL and cutaneous leishmaniasis (CL) infections in HIV negative subjects. Twelve Leishmania stocks were isolated from 8 HIV patients and typed through the electrophoretic analysis of 14 isoenzymes. All the stocks were identified as L. infantum s.l. According to zymodeme classification, the results can be summarized as follows: (i) only half of the subjects were infected with the expected commonest viscerotropic zymodeme in the Mediterranean area, MON 1; (ii) 2 patients were infected with the most widespread agent of CL in Italy, L. infantum MON 24; (iii) one subject was found infected with a zymodeme (MON 78) which, so far, has been found only in Malta as an agent of CL; (iv) one subject was infected with a new zymodeme, MON 136, which shares biochemical characteristics with 2 dermotropic L. infantum zymodemes, MON 78 and MON 111. Thus, half of the HIV patients surveyed displayed severe visceralization of parasites usually showing low virulence in HIV negative subjects.

Aminosidine (paromomycin) in the treatment of leishmaniasis imported into the United Kingdom.

Abstract: We report 11 patients with leishmaniasis from different endemic areas, treated in the UK with intravenous aminosidine alone or in combination with other drugs. Clinical and parasitological cures were achieved in all 7 patients from the Mediterranean zone who had visceral disease, with one relapse. Two of 4 patients with cutaneous or mucosal disease were cured; the other 2, from Iraq and Iran, did not respond. Toxic effects were high-tone deafness in 2 patients, one of whom had pre-existing renal impairment, and transient, mild elevation of serum creatinine in 3. Aminosidine is an effective, tolerable and relatively non-toxic alternative to existing antileishmanial drugs for the treatment of visceral leishmaniasis. Further studies will be needed to assess its place in cutaneous and mucosal disease.

Recombinant Leishmania Hsp90 and Hsp70 are recognized by sera from visceral leishmaniasis patients but not Chagas' disease patients.

Abstract: Approximately 70% of the cDNA clones identified by immunoscreening Leishmania donovani expression libraries with serum from a patient with visceral leishmaniasis (kala-azar) were found to encode the highly conserved Hsp90 and Hsp70 members of the heat shock protein family. Recombinant fusion proteins containing the C-terminal portions of L. donovani Hsp90 and Hsp70 were used as target antigens in enzyme-linked immunosorbent assays of various sera. Sera from four patients with visceral leishmaniasis recognized recombinant Leishmania Hsp90 and Hsp70, while sera from seven patients with Chagas' disease did not, despite the fact that Trypanosoma cruzi Hsp90 and Hsp70 share more than 80% amino acid identity with their counterparts in Leishmania spp. Thus, Leishmania Hsp90 and Hsp70 elicit strong humoral responses and are potential candidates for specific serodiagnostic assays capable of distinguishing between L. donovani and T. cruzi infections.

Visceral leishmaniasis: a model for infection-induced cachexia.

Abstract: Parasitic infections and malnutrition coexist in many tropical and subtropical areas. Studies of Leishmania donovani and of experimentally infected Syrian hamsters have provided important insights into the complex interrelationships between malnutrition and this parasitic disease. Malnutrition, which adversely affects cell-mediated immunity, is associated with the development of visceral leishmaniasis (kala-azar) in children living in endemic areas. In turn, L. donovani can cause wasting as well as hepatosplenomegaly, fever, and anemia. Syrian hamsters infected with L. donovani develop a disease that is comparable to that of humans with kala-azar. Weight loss in infected hamsters is associated with splenic macrophage secretion of potentially catabolic cytokines as measured by the D10.G4.1 assay for interleukin-1 and the L929 cytotoxicity assay for tumor necrosis factor/cachectin. Although decreased food intake contributes to wasting in infected hamsters, studies of skeletal muscle function indicate that it is not the sole factor. Leishmania donovani-infected hamsters have also been used to study drugs with the potential to prevent or reverse cachexia.

Activity of amphotericin B cholesterol dispersion (Amphocil) in experimental visceral leishmaniasis.

Abstract: Standard therapy of human visceral leishmaniasis with parenteral pentavalent antimonial agents is generally curative but has the disadvantages of a 28-day treatment course, occasional treatment failures, and toxicity. The antifungal and antileishmanial agent amphotericin B has been complexed with lipids to develop a less toxic formulation of amphotericin B. Because lipid particles are phagocytized by the reticuloendothelial system, lipid-associated amphotericin B should be concentrated in infected macrophages and be very effective against visceral leishmaniasis. One formulation, amphotericin B cholesterol dispersion (ABCD) (Amphocil), was tested for antileishmanial activity in Leishmania donovani-infected hamsters. In the first experiment, hamsters were infected, administered with the drug 3 days later, and then sacrificed after a further 4 days. ABCD (dose needed to suppress 99% of hepatic parasites compared with controls [SD (99)], 0.4 mg/kg of body weight) was 15 times as effective as conventional amphotericin B [SD (99), 6.0 mg/kg]. Pentavalent antimony in the form of meglumine antimonate had an SD (84) of 416 mg/kg. In a second experiment in which animals were allowed to become more heavily infected, the drug was administered 10 days after infection and the animals were sacrificed after a further 2, 7, or 11 days. ABCD was approximately four times as active as conventional amphotericin B. These experiments suggest that ABCD is at least four times as active as conventional amphotericin B against visceral leishmaniasis and that clinical trials are warranted.

Serodiagnosis and screening of canine visceral leishmaniasis in an endemic area of Corsica: applicability of a direct agglutination test and immunoblot analysis.

Abstract: For effective control of visceral leishmaniasis caused by Leishmania infantum in the Mediterranean area, the detection of infected dogs is of utmost importance. To assess the suitability of a direct agglutination test (DAT) and immunoblot analysis in serodiagnosis and screening of infected dogs under field conditions, a study was performed on 113 dogs in an endemic area of Corsica. Twenty one of 22 parasitologically confirmed cases were correctly diagnosed by both tests, and 100% specificity was found when 11 dogs with other diseases were examined. Interestingly, eight of 80 apparently healthy dogs from the same area were found to be parasite-positive by the DAT test as well as by the immunoblot. Although both tests were equally sensitive and specific, based on both the feasibility of its application in field conditions and ease of performance, we consider the DAT to be more suitable for serodiagnosis and large-scale screening of infected dogs.

Interactions between immunity and chemotherapy in the treatment of the trypanosomiases and leishmaniases.

Abstract: The immune status of a host infected with Trypanosoma spp. or Leishmania spp. can play an important role in successful chemotherapy. In animal models, treatment of African trypanosomiasis with difluoromethylornithine or melarsoprol requires an appropriate antibody-mediated immune response. An intact immune system is also necessary for rapid clearance of trypanosomes from the bloodstream following treatment with suramin or quinapyramine. Similarly, an efficient cell-mediated immune response is required for maximal efficacy of pentavalent antimonials in the treatment of leishmaniasis. However, the potential relationship between parasite-induced or acquired immunosuppression and effective chemotherapy has been poorly studied. Macrophages which have been activated by bacterial cell wall components or gamma-interferon are known to display increased activity against Leishmania donovani or Trypanosoma cruzi. In experimental and clinical visceral leishmaniasis, use of macrophage activators together with pentavalent antimonials has lowered the dose of antimony required to cure the infection.

Leishmania chagasi antigens recognized in cured visceral leishmaniasis and asymptomatic infection.

Abstract: Active visceral leishmaniasis is associated with antigen-specific immunosuppression. However, cured patients develop a cellular immune response associated with resistance to reinfection. Recent studies have identified patients with asymptomatic or subclinical infections, which are also accompanied by an immune response. In order to identify subjects immune to Leishmania chagasi, we performed a skin-test survey in an endemic area in eastern Venezuela. The delayed-type hypersensitivity (DTH) response was assessed in patients cured of visceral leishmaniasis, as well as in their relatives and neighbors. Of the latter, 36 (34.2%) of 105 were positive and 26 (24.7%) of 105 gave intermediate responses. The DTH reaction correlated with age. The antigens recognized by a subgroup of cured patients, those with positive skin-test results, and controls (skin-test negative) were assessed by Western blotting with sera, and T cell immunoblotting with peripheral blood mononuclear cells. No consistent differences between the groups were noted in Western blots with L. chagasi antigens. T cell blots were performed on five patients from each group. For the cured patients and skin-test positive contacts, a significant proliferative response to fraction 12 (< 20.5 kDa) was noted in four of five patients in each group. Cells from three of five cured patients and two of five skin-test-positive patients proliferated in response to fraction 4 (73–115 kDa). The response to other fractions was variable, with only a minority of patients responding to any one fraction. These data suggest that the antigens recognized by patients with evidence of immunity to L. chagasi are quite variable. However, response to antigens in fraction 12 (≤ 20.5 kDa) was noted in most patients, and could be of significance in protective immunity.

Mapping of a visceral leishmaniasis-specific immunodominant B-cell epitope of Leishmania donovani Hsp70.

Abstract: We have shown that a member of the 70-kDa heat shock protein (Hsp70) family is a major target of the humoral immune response during Leishmania donovani infection. A recombinant fusion protein was recognized by sera from 92% (35 of 38) of patients with visceral leishmaniasis, including representatives from each of the major regions where it is endemic. Serological analysis of recombinant Hsp70, expressed by a series of deletion constructs, identified the carboxy-terminal region as the immunodominant site. This region, which is the most evolutionarily divergent part of the molecule, was recognized by all sera from patients with visceral leishmaniasis which exhibited an anti-Hsp70 response. Purified recombinant L. donovani Hsp70 was not recognized by sera from patients with cutaneous leishmaniasis, Chagas' disease, leprosy, malaria, or schistosomiasis. To determine the regions involved in antibody recognition, a series of overlapping peptides were synthesized on polyethylene pins by the Pepscan method, and a hexamer, EADDRA, was identified by the visceral leishmaniasis serum samples as an immunodominant B-cell epitope.

Visceral leishmaniasis in southern Sudan: status of healthy villagers in epidemic conditions.

Abstract: A combination of interview, serology and skin testing was used to investigate the status of apparently healthy villagers during a visceral leishmaniasis epidemic in southern Sudan The number of people who had died equalled the number who were alive at the time of the survey The direct agglutination test (DAT) identified 10% of the people as being serologically positive Most young children (36/39) and 34% (22/64) of adults had neither positive serology nor skin test About 64% (42/66) of adults had positive skin tests In two villages, 54% and 76% of those over four years of age showed evidence of having been infected The mortality associated with infection was estimated as at least 69%; 25% of those infected appeared to have cured spontaneously The outcome for the remaining 6% was still doubtful Even in this devastating epidemic there is, therefore, evidence of a considerable amount of infection without severe disease Serological tests, while useful clinically, are apparently not useful for detecting early cases Combined skin testing and serology produces a comprehensive though partially hypothetical picture

Comparison of parasitological and immunological methods in the diagnosis of leishmaniasis in Ethiopia

Abstract: The sensitivity and specificity of parasite demonstration methods (smear, culture and histology) and serological assays (enzyme-linked immunosorbent assay [ elisa ], direct agglutination test and immunoblot) were compared in the diagnosis of leishmaniasis in Ethiopia. Culture was found to be the most sensitive diagnostic method, followed by elisa , for the diagnosis of cutaneous leishmaniasis (CL). When the clinical type of CL was taken into consideration, serological and parasitological methods were equally good for the diagnosis of diffuse cutaneous leishmaniasis. Overall, the serological assays were not sensitive enough to diagnose all the parasitologically confirmed cases of localized cutaneous leishmaniasis. Both groups of diagnostic methods performed equally well in the diagnosis of visceral leishmaniasis patients. In cases of CL where clinical diagnosis was a problem and histology could not give a definitive diagnosis due to the absence of demonstrable parasites, one of the serological assays, preferably elisa , was very useful in establishing the final diagnosis.

Leishmaniasis: A Rare Cause of Unexplained Fever in a Renal Graft Recipient

Abstract: We report a case of visceral leishmaniasis in a 38-year-old renal transplant recipient living in an endemic country. Antimonial derivatives induced a rapid remission. A review of the literature disclo

Diminished In Vitro Production of Interleukin-1 and Tumor Necrosis Factor-α during Acute Visceral Leishmaniasis and Recovery after Therapy

Abstract: Disturbance of T cell-mediated immunity has been reported in acute visceral leishmaniasis (AVL). In a study of 16 patients with AVL, defective production of interleukin-1 (IL-1) by peripheral blood mononuclear cells was demonstrated in response to leishmania antigens, heat-killed Listeria organisms, and lipopolysaccharide when compared to posttherapy values or controls. This global defect in IL-1 production was corrected after successful therapy. Twelve of 16 patients responded with a greater than or equal to 2.5-fold increase in IL-1 production that correlated with clinical cure, P less than .01. Depressed production of tumor necrosis factor (TNF) was leishmania antigen-specific and similarly recovered after therapy. In vitro TNF production during the follow-up period did not correlate with clinical status but high serum levels were associated with AVL. Since T cells are activated by processed antigens presented on class II major histocompatibility molecules and by newly synthesized IL-1, defective IL-1 production may contribute to the immunosuppression observed in AVL.

Antigenic differences among Leishmania amazonensis isolates and their relationship with distinct clinical forms of the disease

Abstract: Immunoblot analysis was used to investigate antigenic differences among clinical isolates of Leishmania amazonensis and their role in the etiology of the diseases. Western blots of promastigote homogenates were analyzed with either monoclonal antibodies (MAbs) specific for the L. mexicana complex (M-4, M-6, M-9 and M-11) or polyclonal sera from L. amazonensis infected patients with the various forms of clinical disease. In the case of the MAbs, no significant variation was observed among the strains of L. amazonensis, isolated from cases of cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL), diffuse cutaneous leishmaniasis (DCL), visceral leishmaniasis (VL) or post kala-azar dermal leishmaniasis (PKDL), in either the relative morbility (Mr) or the quantitative amount (intensity) of the antigenic determinats. In the case of the sera of the infected patients, the patterns of antigenic reactivity of these strains revealed that, despite showing the presence of shared antigens, differences were observed between some of the antigenic components of the various isolates of L. amazonensis that were recognized by a single serum. Differences were also demonstrated between the antigenic determinants of a single isolate of L. amazonensis that were recognized by the different patient's sera. No apparent association was consistently found, however, between the Mr components identified in these isolates and clinical form of the disease or the geographical area of isolation. In addition, the spectrum of antigens recognized by the sera from patients with the same clinical form were not identical; although in some instances, similar Mr antigens were shared. These results indicate that isolates of L. amazonensis are not antigenically identical (homogeneous) and that the immune responses (antibodies) observed among infected patients are heterogeneous.

A preliminary report on the natural leptomonad infection of phlebotomus majorin an endemic focus of visceral leishmaniasis (vl) in fars province, south of iran

Abstract: In order to determine the vector of visceral leishmaniasis in the endemic focus of Fars Province in southern Iran, collection and dissection of sand- flies were carried out in the town of Ghjr in Firooz - abad district. A total of 270 sand- flies were dissected. They consisted of Ph. Alexandri, Ph. sergenti Ph. papatasi and Ph. major. Five out of 150 Ph. major was found infected with promastigotes three of them with the parasites in the gut as well as the head. This is the first report about the probable vector of kala - azar in Iran.

The Indian langur: preliminary report of a new nonhuman primate host for visceral leishmaniasis.

Abstract: Described are the susceptibility of the Indian langur (Presbytis entellus) to Leishmania donovani and the consequent haematological and serum biochemical changes. The host response to antileishmanial chemotherapy and the immunological profile were also examined. Each langur was inoculated intravenously with 1 x 10(8) amastigotes; a spleen biopsy carried out on day 35 post-infection (p.i.) revealed 10-13 L. donovani bodies per 500 cell nuclei, which reached a maximum of 130-195 at death (day 105-110 p.i.). The infected monkeys lost body weight, developed severe anaemia, lymphocytosis, hyperproteinaemia, hypergammaglobulinaemia, hypoalbuminaemia and an increase in the level of alkaline phosphatase and alanine aminotransferase (AAT). Treatment with sodium stibogluconate (60 mg Sb5+ per kg body weight intramuscularly for 10 days) reduced the number of spleen parasites (0-1 amastigotes per 500 cell nuclei) but after the therapy the parasites appeared in the skin, which had previously been free of infection. Relapse occurred on day 30 post-treatment (10-24 amastigotes per 500 cell nuclei) and the parasites were resistant to repeat intensive therapy (120 mg Sb5+ per kg per day x 30 days). The stibogluconate treatment caused a proportionate reduction in the haematological and biochemical parameters to normal values except for alkaline phosphatase and AAT, which remained elevated. The level of IgG antibodies, which rose during the infection, rapidly fell to the pretreatment value following the first therapeutic schedule and then increased a second time coinciding with relapse. Our findings suggest that langurs could serve as acceptable models for human visceral leishmaniasis.