Showing papers on "Visceral leishmaniasis published in 1983"

Quantitation of amastigotes of Leishmania donovani in smears of splenic aspirates from patients with visceral leishmaniasis.

Abstract: During a 20-month period, more than 500 splenic aspirations were performed in 89 patients with suspected or proven visceral leishmaniasis. The two complications which occurred (intra-abdominal bleeding and penetration of the intestine in one patient each) both resolved with conservative management. Parasite density in splenic aspirate smears was graded on a logarithmic scale from 0 (no parasites in 1,000 microscopic fields) to 6+ (greater than 100 parasites per microscopic field). Among 46 newly diagnosed and 17 relapsed or drug-resistant patients with visceral leishmaniasis, the average initial parasite grade was 4.35 +/- 0.92 (mean +/- SD) and 4.15 +/- 1.37, respectively. The grading system was useful in measuring the speed of response to treatment, and in distinguishing slow responders from nonresponders. This was especially valuable for managing patients with drug-resistant visceral leishmaniasis. The system also provided a means of comparing the efficacy of different treatment regimens, and for calculating the optimum duration of treatment.

Immunosuppression in Kenyan visceral leishmaniasis.

Abstract: Cell-mediated immune responses were evaluated in 15 patients with active visceral leishmaniasis from Masinga location in eastern Kenya where the disease is endemic. Age and sex matched controls were selected from a village school in the same area. In vivo studies were carried out by skin testing with leishmanin, tuberculin, streptococcal and candida antigens. Lymphocyte blastogenic transformation to the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A) and the antigens purified protein derivative (PPD), streptokinase-streptodornase (SKSD) and leishmanial antigen (LA) was studied in vitro. The results showed that immunosuppression in visceral leishmaniasis in Kenya was both specific and non-specific. In the majority of patients there was complete anergy to all antigens in vivo and in vitro. The suppression of responses to mitogens was less marked. Recovery of non-specific responses preceded the development of specific immunity. In a small number of patients (23%) immune unresponsiveness to leishmanial antigens persisted 1 year after parasitological cure.

Immunofluorescent antibody test in American visceral leishmaniasis: sensitivity and specificity of different morphological forms of two Leishmania species.

Abstract: This study was designed to determine which morphologic form and species of Leishmania is most suitable for detection of antibody in sera from American visceral leishmaniasis (AVL) patients by the indirect fluorescent antibody test (IFAT). Promastigotes and amastigotes of Leishmania mexicana or Leishmania donovani chagasi were used as sources of antigen. A total of 70 sera, including 30 from AVL patients, 30 from healthy subjects and 10 from Chagas' disease patients, were used in the study. Titers of antibody up to a dilution of 1:64 were found with all four antigens. At a titer of 1:128, the sensitivity of the IFAT using L. d. chagasi promastigotes as a source of antigen was 100% and the specificity at a titer of 1:32 was 98%. Although the sensitivity of the amastigote forms was close to 100% at a similar titer, the specificity at a titer of 32 using the L. d. chagasi amastigotes was 91% and using L. mexicana amastigotes was only 80%. The L. d. chagasi promastigote antigen was also the one that showed less cross reaction with sera from Chagas' disease patients. Since cross reactivity between Trypanosoma cruzi and Leishmania species is well known in serological tests, and minimizing of such cross reactivity is of critical importance for diagnosis, we suggest that L. d. chagasi promastigotes should be the antigen of choice for diagnosis of visceral leishmaniasis by IFAT in areas also endemic for trypanosomiasis.

Circulating Immune Complexes and Rheumatoid Factor in Schistosomiasis and Visceral Leishmaniasis

Abstract: Circulating immune complexes, measured by the C1q binding and Raji cell radioimmunoassays, were detected in 16 of 25 (64%) patients with schistosomiasis alone, in all 13 patients (100%) with schistosomiasis infection associated with prolonged bacteremia by salmonella organisms, and in 15 of 18 (83%) patients with visceral leishmaniasis. The C3 levels in the serum of patients with schistosomiasis, with and without prolonged salmonella bacteremia, were significantly lower in those with renal disease. Further, in patients with schistosomiasis alone, the absence of renal involvement was positively associated with C1q binding within the normal range (P = 0.015) and the presence of IgM rheumatoid factor in serum (P = 0.04). In six of eight patients with visceral leishmaniasis treated with a pentavalent antimonial, there was a fall in Raji cell binding, suggesting indirectly that the parasitic antigen may be involved in the pathogenic immune complexes in serum.

An enzyme-linked immunosorbent assay (ELISA) for field diagnosis of visceral leishmaniasis.

Abstract: A simplified enzyme-linked immunosorbent assay (ELISA) was evaluated as a diagnostic test for visceral leishmaniasis in the field on 222 individuals with splenomegaly and 110 controls The test was shown to have a sensitivity of 984% and specificity of 100% when compared with parasite identification by splenic aspiration The data indicate that the ELISA is an accurate, safe, and economical alternative to splenic aspiration for the diagnosis of visceral leishmaniasis

A Comparison of Three Dosage Regimens of Sodium Stibogluconate in the Treatment of Visceral Leishmaniasis in Kenya

Abstract: A prospective randomized trial of three dosage regimens of sodium stibogluconate (PentostamR; Wellcome Foundation, London) to treat visceral leishmaniasis was conducted. Previously untreated patients were randomized to receive 31 doses of sodium stibogluconate (10 mg Sb/kg of body weight per dose) administered once daily for 31 days (group A), every 12 hr for 15 days (group B), or every 8 hr for 10 days (group C). Of the 29 patients who completed treatment, seven of 10 in group B and all of the patients in groups A and C responded to treatment and remained well for one year. One patient in group B failed to respond to treatment, and two others in group B initially responded to treatment but relapsed six weeks after discharge. None of the treatment regimens was toxic. Parasites disappeared from splenic aspirates most quickly and hemoglobin levels rose most rapidly in patients receiving sodium stibogluconate every 8 hr. Treatment of visceral leishmaniasis in Kenya with sodium stibogluconate at a dose of 10 mg Sb/kg every 8 hr for 10 days appears to be a safe alternative to conventional treatment. Its efficacy should be confirmed in a larger number of patients. Visceral leishmaniasis is a chronic infectious disease caused by the protozoan parasite Leishmania donovani, is transmitted by phlebotomine sandflies, and is characterized by splenomegaly, anemia, fever, weight loss, malnutrition, immune

Leishmaniasis in tuscany (Italy): VII. Studies on the role of the black rat, Rattus rattus, in the epidemiology of visceral leishmaniasis

Abstract: The recent finding that four Leishmania isolates from Rattus rattus are enzymologically identical to L. infantum , aetiological agent of human and canine visceral leishmaniasis in the Mediterranean area, has stimulated further research on the role of R. rattus in the epidemiology of visceral leishmaniasis in Tuscany, Italy. The present work has led to the following results: (a) R. rattus experimentally infected with L. infantum displayed a general resistance to the parasite, even though it appeared that a very low number of amastigotes persisted in the animal for a long period; (b) Phlebotomus perniciosus and P. perfiliewi induced to feed on rats, with either a massive visceral infection or a subpatent immunodepressed infection, became infected, though in different proportions; (c) P. perniciosus and P. perfiliewi were readily attracted to, and fed on, the black rat in nature. These findings, together with those obtained earlier, strongly suggest that the black rat may be one of the wild reservoirs of L. infantum in the areas under study.

Leishmaniasis in Brazil. XIX: Visceral leishmaniasis in the Amazon Region, and the presence of Lutzomyia longipalpis+ on the Island of Marajo, Para State

Abstract: Sporadic cases of visceral leishmaniasis in Amazonian Brazil appear limited to Para State, in the lower Amazon valley and principally near the Atlantic coast. The fox Cerdocyon thous (L.) has been incriminated as a natural host of the causative parasite, Leishmania donovani chagasi, but past doubts have existed over the identification of the most likely vector as Lutzomyia (Lutzomyia) longipalpis (Lutz & Neiva, 1912). Investigations on two of five recent cases of visceral leishmaniasis of man in the Districts of Cachoeira do Arari and Salvaterra, on the eastern part of the Island of Marajo, Para showed undoubted Lu. longipalpis to be abundant in one house and in numerous chicken-houses. This is the first record of Lu. longipalpis on Marajo Island, and the finding supports previous implication of this sandfly in the epidemiology of visceral leishmaniasis in other parts of Para. Morphological differences have been noted between this insect from Marajo and other specimens from more highly endemic regions in the States of Ceara and Minas Gerais, Brazil.

The Coombs direct antiglobulin test in Kenyans

Abstract: The direct antiglobulin test (DAT) was performed on 243 subjects in Kenya. A high incidence of positive DAT was found in children with malaria of whom 70% had RBCs coated with IgG, C3 and C4 either separately or together. Only 12% of paediatric patients with conditions other than malaria had a positive DAT. Most positive DATs in association with malaria occurred in children between 18 months and five years of age. There was a lower incidence of positive DAT in Kikuyu children from an area of low malarial transmission than in children from other tribal groups who reside in areas of high malaria endemicity. A high rate of positive DAT was also found in patients with visceral leishmaniasis. Interestingly there was an association of IgG and C4 but without C3 on red cells of five patients with visceral leishmaniasis and two schoolchildren from an area endemic for visceral leishmaniasis. This combination was not found on other patients.

Antiactin and antitubulin antibodies in canine visceral leishmaniasis.

Abstract: Visceral leishmaniasis, a chronic and often fatal disease, is caused by the protozoan parasite Leishmania donovani. Both specific and nonspecific antibodies are produced in the course of the disease, and autoantibodies may be involved in pathogenesis. Tubulin and actin have been found to be associated with L. donovani. To learn whether antiactin and antitubulin antibodies are present in visceral leishmaniasis, we tested sera from 263 infected dogs by enzyme-linked immunosorbent assay for antibodies to the antigens L. donovani, actin, and tubulin. All samples reacted positively with L. donovani, and a high percentage reacted positively with all three antigens. Sera from 202 uninfected dogs were also tested, none reacted with L. donovani antigen, although positive reactions were observed for 8 of the samples with actin or tubulin. It was found that the antibody-antigen reaction occurred at the Fab portion of the immunoglobulin molecule. Competitive enzyme immunoassays showed that the reaction was inhibited if the positive serum was first incubated with L. donovani antigen, actin, or tubulin and then tested by enzyme-linked immunosorbent assay. These results suggest that antiactin and antitubulin antibodies are present in the sera of dogs infected with visceral leishmaniasis.

Resurgence of visceral leishmaniasis in Bangladesh

Abstract: Out of 218 suspected cases of kala-azar from different parts of Bangladesh, 59 could be confirmed; and out of 41 patients with suspected skin lesions, 6 were confirmed as post-kala-azar dermal leishmaniasis. Confirmation of diagnosis was based on the demonstration of L-D bodies in tissue specimens (spleen and liver (after puncture) or skin scrapings).The complement fixation test (CFT) and aldehyde test (AT) were positive in all but one case of kala-azar. Their usefulness in the diagnosis of the disease has been emphasized. The aldehyde test is very simple to perform and does not require any equipment or electricity; it can therefore be used as a screening test in rural areas.Failure of the organism to grow in NNN medium in 2 cases and failure to maintain organisms isolated from some other cases for more than 2-3 weeks in the culture medium indicate the possibility that different strains were involved. As the number of kala-azar cases appears to be increasing, the threat of an epidemic is real.

Visceral leishmaniasis complicating systemic lupus erythematosus

Abstract: Active systemic lupus erythematosus in a 32-year-old Chinese woman was successfully controlled by plasmapheresis and steroids. However, occult visceral leishmaniasis was uncovered during therapy and responded to appropriate treatment.

Leishmaniasis in The Gambia. 2. A study of possible vectors and animal reservoirs, with the first report of a case of canine leishmaniasis in The Gambia

Abstract: Following the detection of two cases of leishmaniasis in The Gambia, the possible vectors and animal reservoirs were studied. A total of 5, 158 phlebotomine sandflies, in 20 species and subspecies were captured, including 98 males and 61 females of Phlebotomus duboscqi. This species is a vector of cutaneous leishmaniasis in Senegal and must be suspected as a vector in The Gambia; it was captured close to the dwellings of both patients and from rodent burrows, including those of Mastomys erythroleucus, a known reservoir of cutaneous leishmaniasis in Senegal. We report the first finding in The Gambia of visceral leishmaniasis in a dog captured near the house of the patient with visceral leishmaniasis. This strongly suggests that dogs could be a reservoir of this infection in this area. The vector was not determined.

Visceral spreading depletion of thymus-dependent regions and amyloidosis in mice and hamsters infected intradermally with Leishmania isolated from Sudanese cutaneous leishmaniasis.

Abstract: Eighteen outbred mice and 21 golden hamsters were each inoculated intradermally with 2 X 10(6) Leishmania amastigotes obtained from 1 case of Sudanese cutaneous leishmaniasis. The skin lesions, spleen, lymph nodes, liver and kidney were examined by light-, polarizing-, and electron microscope at 5, 9 and 18 weeks after inoculation. The aim of the investigations was to follow the development of the inflammatory reaction and the change of the morphology of the lymphoid organs during the infection. In all the mice and in the majority of the hamsters visceral leishmaniasis developed which was characterized by a "noncure" type of cellular reaction, a selective T-cell depletion in the lymph nodes and the spleen, and the development of a reactive, systemic amyloidosis. These findings point to the failure of the acquired resistance against Leishmania to develop. In some of the hamsters the response was of the "cure" type without the development of amyloidosis. At the site of the inoculation the lesions healed suggesting the positive role of necrosis and the elimination of the parasites through the ulcer in the healing process. Electron microscopy showed erythrophagocytosis in the spleen of the 2 mice examined presenting an experimental evidence of the destruction of the red blood cells, which is a common feature of human kala-azar.

Investigation of animal reservoirs of visceral leishmaniasis and the isolation of Leishmania major in Marigat, Baringo District, Kenya

Abstract: Animals were trapped in Marigat, Baringo District to investigate animal reservoirs of visceral leishmaniasis in an endemic focus of the disease. Several species of rodents, carnivores and reptiles were captured. Specimens of spleen, liver and blood tissues were taken from the animals. The specimens were triturated into sterile saline and then cultured into NNN medium, and some of it injected into hamsters intraperitoneally. Skin biopsies were also taken and cultured in NNN medium. Slide smears of all the tissues taken were made stained with Giemsa stain and examined under the microscope for amastigotes. Four isolates of leishmanial parasites were made from a gerbil and three monitor lizards.

Leishmaniasis in The Gambia. I. A case of cutaneous leishmaniasis and a case of visceral leishmaniasis.

Abstract: Leishmaniasis is thought to be rare in The Gambia but in June 1980 two patients with this infection were seen at Fajara, one with cutaneous leishmaniasis and one with visceral leishmaniasis. A possible diagnosis of visceral leishmaniasis was considered only late in the course of the illness of the second patient who died a few days after specific chemotherapy was started. Visceral leishmaniasis must be considered as a possible cause of fever and splenomegaly in The Gambia and in adjacent parts of West Africa.

Clinical presentation of visceral leishmaniasis in Kenya: a prospective study of 64 patients.

Abstract: Clinical and laboratory findings of a series of 64 consecutive patients with visceral leishmaniasis are presented. The diagnosis was established by demonstration of parasites in splenic aspirates. Findings are discussed in comparison with those of former reports from Kenya and elsewhere.