-
Trends in Parasitology Jan 2020
Review
Topics: Animals; Dogs; Host-Parasite Interactions; Humans; Leishmania infantum; Leishmaniasis, Visceral; Life Cycle Stages
PubMed: 31757772
DOI: 10.1016/j.pt.2019.10.006 -
Parasitology Research Feb 2023Human visceral leishmaniasis (HVL) is a neglected disease that occurs in 98 countries on five continents, and it is endemic in tropical and subtropical regions. In South...
Human visceral leishmaniasis (HVL) is a neglected disease that occurs in 98 countries on five continents, and it is endemic in tropical and subtropical regions. In South America, the etiological agent of HVL is Leishmania infantum (syn. Leishmania chagasi), mainly transmitted through the bite of an infected sandfly female from the genus Lutzomyia. In American HVL endemic areas, the occurrence of asymptomatic infection is common, which contributes to the possibility of L. infantum transmission during a blood transfusion. To know the prevalence of L. infantum asymptomatic infection in blood donors from the microregion of Adamantina, we investigated 324 peripheral blood samples from donors through immunofluorescence (IFAT) and PCR-RFLP techniques. Seven blood samples (2.16%) tested positive for Leishmania by IFAT, and from those, six presented positive results by PCR (85.71%), which were later identified as L. infantum by RFLP. The presence of L. infantum in the peripheral blood of blood donors supported the hypothesis of transmission by blood transfusion and points to the need to include tests for visceral leishmaniasis in blood bank screening tests and pre-storage measures, especially in endemic areas to prevent the exponential increase of HVL by blood transfusion.
Topics: Animals; Humans; Female; Leishmania infantum; Leishmaniasis, Visceral; Blood Donors; Asymptomatic Infections; Polymerase Chain Reaction; Psychodidae
PubMed: 36567398
DOI: 10.1007/s00436-022-07770-7 -
Parasitology Today (Personal Ed.) May 2000
Review
Topics: Africa; Americas; Animals; DNA Probes; DNA, Protozoan; Europe; Humans; Leishmania infantum; Leishmaniasis, Visceral; Nucleic Acid Hybridization; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Random Amplified Polymorphic DNA Technique; Sequence Analysis, DNA
PubMed: 10782075
DOI: 10.1016/s0169-4758(00)01637-9 -
Acta Tropica Aug 2011Leishmaniasis due to Leishmania infantum (syn. L. chagasi) infection is a zoonotic disease present mainly in Mediterranean basin, central Asia and Brazil. Besides a... (Review)
Review
Leishmaniasis due to Leishmania infantum (syn. L. chagasi) infection is a zoonotic disease present mainly in Mediterranean basin, central Asia and Brazil. Besides a limited number of human cases of clinical visceral leishmaniasis, a great number of infections remains asymptomatic. In this review, the prevalence of asymptomatic carriers of L. infantum was evaluated worldwide using parasitological methods or indirect testing such as a skin test or serology. The consequences of the presence of asymptomatic carriers on parasite transmission by blood donation or the development of clinical visceral leishmaniasis in immunocompromised individuals and its possible role as reservoir are discussed.
Topics: Asia, Central; Asymptomatic Infections; Brazil; Carrier State; Disease Reservoirs; Humans; Leishmania infantum; Leishmaniasis, Visceral; Mediterranean Region; Prevalence
PubMed: 21679680
DOI: 10.1016/j.actatropica.2011.05.012 -
Transactions of the Royal Society of... Jan 2010This study used a PCR-RFLP test to determine the presence of Leishmania (Leishmania) chagasi in 16 captive wild felids [seven Puma concolor (Linnaeus, 1771); five...
This study used a PCR-RFLP test to determine the presence of Leishmania (Leishmania) chagasi in 16 captive wild felids [seven Puma concolor (Linnaeus, 1771); five Panthera onca (Linnaeus, 1758) and four Leopardus pardalis (Linnaeus, 1758)] at the zoological park of the Federal University of Mato Grosso, Brazil. Amplification of Leishmania spp. DNA was seen in samples from five pumas and one jaguar, and the species was characterized as L. chagasi using restriction enzymes. It is already known that domestic felids can act as a reservoir of L. chagasi in endemic areas, and further studies are necessary to investigate their participation in the epidemiological chain of leishmaniasis.
Topics: Animals; Animals, Zoo; Brazil; DNA, Protozoan; Felidae; Gene Amplification; Leishmania infantum; Leishmaniasis, Visceral; Panthera; Polymerase Chain Reaction; Puma
PubMed: 19740501
DOI: 10.1016/j.trstmh.2009.08.003 -
Veterinary Dermatology Apr 2014Canine leishmaniosis, a zoonotic infectious disease caused by Leishmania infantum (syn. L. chagasi), is fairly common in endemic areas, and skin lesions are the most... (Review)
Review
BACKGROUND
Canine leishmaniosis, a zoonotic infectious disease caused by Leishmania infantum (syn. L. chagasi), is fairly common in endemic areas, and skin lesions are the most frequent clinical manifestation. Despite the large volume of relevant scientific information, there is a relative paucity of up-to-date review articles on the cutaneous manifestations of the disease.
HYPOTHESIS/OBJECTIVES
This review provides current information on the macroscopic and histological skin lesions of dogs with leishmaniosis and comments on their pathogenesis and definitive diagnosis.
METHODS
Published articles have been thoroughly reviewed and the retrieved information has been used and supplemented as appropriate with the authors' clinical experience.
RESULTS
The main clinicopathological presentations of canine leishmaniosis are exfoliative, ulcerative, nodular, sterile pustular and papular dermatitis and nodules at the site of parasite inoculation. Histopathology is usually dominated by mononuclear inflammatory infiltrates; immunohistochemical findings are variable, and Leishmania amastigotes are present in both diseased and normal-looking skin of dogs with leishmaniosis. Definitive diagnosis of the skin lesions in a dog with leishmaniosis is based on their macroscopic appearance, exclusion of main differentials, histopathology, demonstration of the parasite in the skin and complete response to antileishmanial treatment.
CONCLUSIONS AND CLINICAL IMPORTANCE
Canine leishmaniosis due to L. infantum is characterized by diverse cutaneous manifestations that may reflect different host-parasite relationships. Furthermore, different types of skin lesions may occur, in various combinations, in the same dog. The definitive diagnosis of these lesions is based on clinical and laboratory examinations and on the response to antileishmanial treatment.
Topics: Animals; Dog Diseases; Dogs; Leishmania infantum; Leishmaniasis, Cutaneous; Leishmaniasis, Visceral
PubMed: 24461051
DOI: 10.1111/vde.12105 -
Journal of Proteomics Sep 2020Leishmania infantum chagasi is the primary etiological agent of visceral leishmaniasis in Latin America, a lethal disease that afflicts hundreds of thousands of people...
Leishmania infantum chagasi is the primary etiological agent of visceral leishmaniasis in Latin America, a lethal disease that afflicts hundreds of thousands of people worldwide every year. Previous studies have shown that the parasite releases microvesicles known as exosomes, which prolong and exacerbate infection in the vertebrate vector. However, little is known of their role in the insect vector, the sand fly Lutzomyia longipalpis. Exosomes were isolated from cultured L. i. chagasi in logarithmic (procyclic) (LOG) and stationary phase (metacyclic-like) (STAT) growth stages, which are the parasite stages found in the vector, and submitted to proteomic analysis. Our studies showed that exosomes from LOG and STAT L. i. chagasi display discrete protein profiles. The presence of approximately 50 known virulence factors was detected, including molecules for immunomodulation and evasion (GP63, EF1α, Oligopeptidase), increased pathogenicity (Casein kinase, KMP-11, Cysteine Peptidase and BiP) and parasite protection (Peroxidoxin). Additionally, the majority of ontological terms were associated with both exosome phases, and no substantial ontological enrichment was observed associated with any of the two exosomal stages. We demonstrated that LOG exosomes show a marked increase in protein number and abundance, including many virulence factors, compared to STAT L. i. chagasi exosomes. SIGNIFICANCE: The knowledge of the role of Leishmania exosomes on leishmaniasis opened up a new world of potential and complexity regarding our understanding of the disease. In Brazil the majority of visceral leishmaniasis cases are caused by the parasite Leishmania infantum chagasi and transmitted by the vector Lutzomyia longipalpis. While Leishmania exosomes were found to play an active role in the mammalian host, little is understood about their effects on the sand fly, or how they might impact on the insect infection by the parasite. For this reason, we isolated exosomes from two developmental stages of L. i. chagasi that occur within the insect with a view to identifying and describing the alterations they undergo. We have identified many hundreds of proteins within both exosome phases and have developed a structure by which to examine potential candidates. Our findings regarding the composition of the exosome proteome raise many questions regarding their function and provide compelling evidence that exosomes play an active role in the parasite's development within the sand fly.
Topics: Animals; Brazil; Exosomes; Leishmania infantum; Leishmaniasis, Visceral; Proteomics; Psychodidae
PubMed: 32673755
DOI: 10.1016/j.jprot.2020.103902 -
Revista Brasileira de Parasitologia... 2015Canine visceral leishmaniasis (CVL) is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty...
Canine visceral leishmaniasis (CVL) is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty in obtaining diagnostic evidence of high sensitivity and specificity. The purpose of this study was to diagnose CVL in urinary sediment of 70 dogs of different breeds, sexes and ages from the veterinary hospital of the Federal University of Piauí and Zoonosis Control Center of Teresina, Brazil. The serological tests were TR DPP® for CVL and enzyme-linked immunosorbent assay (ELISA) for CVL, parasitological exams of bone marrow and lymph nodes and urine sediment cultures. Leishmania was detected in the bone marrow and/or lymph node of 61.0% of the animals (43/70), and urine sediment culture was positive in 9.30% (4/43) of these animals. In the serological exams, 70.0% (49/70) were reactive using the DPP and 78.2% (55/70) were reactive using ELISA. The goal of this study was to diagnose the presence of L. (infantum) chagasi in a culture of urinary sediment.
Topics: Animals; Dog Diseases; Dogs; Female; Leishmania infantum; Leishmaniasis, Visceral; Male; Urine
PubMed: 25909260
DOI: 10.1590/S1984-29612014086 -
Parasitology Research Sep 2021Functionally, cluster of differentiation 14 (CD14) is a co-receptor of the complex formed by lipopolysaccharide (LPS) and LPS-binding protein expressed on the membrane...
Functionally, cluster of differentiation 14 (CD14) is a co-receptor of the complex formed by lipopolysaccharide (LPS) and LPS-binding protein expressed on the membrane of a variety of cells. However, CD14 can be shed from the cell membrane into the circulation as soluble CD14 (sCD14) upon cell activation. Previously, our group reported that elevated sCD14 serum levels were associated with the clinical and laboratory findings in the context of visceral leishmaniasis (VL), but not in the context of LPS stimulation or bacterial infection. In the present study, we investigated the secretion dynamics of sCD14 in the context of Leishmania infantum (syn. L. chagasi) in vitro infection. Macrophages from treated VL patients and delayed-type hypersensitivity positive (DTH) subjects were infected with L. infantum (syn. L. chagasi) promastigotes, and the infection index was evaluated (number of amastigotes per 100 infected macrophages). Additionally, the levels of sCD14, Inteleukin (IL)10, IL-6 and tumour necrosis factor alpha (TNF-α) were measured in the culture supernatants using the Luminex assay. Interestingly, the release of sCD14 was inversely correlated with the L. infantum (syn. L. chagasi) infection index. Of note, the release of sCD14 was upregulated and downregulated in the context of infected macrophages from DTH subjects and treated VL patients, respectively. Additionally, we also observed that the levels of sCD14 in the culture supernatants were positively correlated with the levels of TNF-α, IL-6 and IL-10. Therefore, our data suggest that macrophages from treated VL patients and DTH subjects respond differently to L. infantum (syn. L. chagasi) infection in the context of the release of sCD14; therefore, the release of sCD14 may be associated with the outcome of VL.
Topics: Animals; Cell Differentiation; Humans; Leishmania infantum; Leishmaniasis, Visceral; Lipopolysaccharide Receptors; Macrophages
PubMed: 34351491
DOI: 10.1007/s00436-021-07258-w -
Veterinary Pathology Mar 2014In dogs with symptomatic or asymptomatic leishmaniasis, Leishmania infantum appears to induce a mixed Th1/Th2 immune response that in the sick dog may eventually result... (Review)
Review
In dogs with symptomatic or asymptomatic leishmaniasis, Leishmania infantum appears to induce a mixed Th1/Th2 immune response that in the sick dog may eventually result in tissue damage via different pathomechanisms, notably granulomatous inflammation (eg, nodular dermatitis, osteomyelitis), immune complex deposition (eg, glomerulonephritis), and/or autoantibody production (eg, polymyositis). This is a compensatory but detrimental mechanism generated mainly because of the insufficient killing capacity of macrophages against the parasite in the susceptible dog. Clinical disease is typically exemplified as exfoliative and/or ulcerative dermatitis, with or without nasodigital hyperkeratosis and onychogryphosis, glomerulonephritis, atrophic myositis of masticatory muscles, anterior uveitis, keratoconjunctivitis sicca, epistaxis, and/or polyarthritis, appearing alone or in various combinations. The pathogenesis of these clinical conditions has recently been highlighted, to a greater or lesser extent. The usually subclinical conditions expressed as chronic colitis, chronic hepatitis, vasculitis, myocarditis, osteomyelitis, orchiepididymitis, and meningoencephalomyelitis, though uncommon, are of pathologic importance from a differential point of view. The leading cause of death among canine leishmaniasis patients is chronic proteinuric nephritis that may progress to end-stage kidney disease, nephrotic syndrome, and/or systemic hypertension. However, even the asymptomatic proteinuria, when profuse, may be a serious problem because it predisposes to arterial thromboembolism and eventually contributes to the deterioration of the body condition.
Topics: Animals; Dog Diseases; Dogs; Immunity, Cellular; Kidney Failure, Chronic; Leishmania infantum; Leishmaniasis, Visceral
PubMed: 24510947
DOI: 10.1177/0300985814521248