Leishmania

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Leishmania

 [lēsh-ma´ne-ah]
a genus of protozoa comprising parasites of worldwide distribution, several species of which are pathogenic for humans. All species are morphologically indistinguishable, and therefore the organisms have usually been assigned to species and subspecies according to their geographic origin, the clinical syndrome they produce, and their ecologic characteristics. They have also been separated based on their tendency to cause visceral, cutaneous, or mucocutaneous leishmaniasis. In some classifications, Leishmania is grouped in four complexes comprising species and subspecies: L. donovani, L. tropica, L. mexicana, and L. viannia.
Life cycle of Leishmania. From Mahon and Manuselis, 2000.
Leishmania brazilien´sis Leishmania viannia.
Leishmania donova´ni donova´ni a subspecies of the L. donovani complex causing the classic form of visceral leishmaniasis in India. It is transmitted by the sandfly Phlebotomus argentipes, with humans being the only major reservoir hosts. Called also L. donovani.
Leishmania ma´jor a species of the L. tropica complex, transmitted by Phlebotomus papatasi, causing the rural form of Old World cutaneous leishmaniasis. Called also L. tropica major.
Leishmania mexica´na a complex comprising the species and subspecies causing the New World form of cutaneous leishmaniasis in humans: L. m. mexicana, L. m. amazonensis, and L. pifanoi.
Leishmania tro´pica
1. a complex comprising the species causing the Old World form of cutaneous leishmaniasis: L. tropica, L. major, and L. aethiopica.
2. a species of the L. tropica complex causing the urban form of Old World cutaneous leishmaniasis. It is found in Iran, Iraq, and India, transmitted by Phlebotomus sergenti; and in southern France, Italy and certain Mediterranean islands, transmitted by P. papatasi. Human to human transmission may also occur.
Leishmania vian´nia a taxonomic complex comprising the subspecies that cause mucocutaneous leishmaniasis in its various forms; all of the subspecies develop in the midgut, foregut, and hindgut of their sandfly vectors. Formerly called L. braziliensis.

Leishmania

(lēsh-man'ē-ă), Avoid the mispronunciation līshmā'nē-ă.
A genus of digenetic, asexual, protozoan flagellates (family Trypanosomatidae) that occur as amastigotes in the macrophages of vertebrate hosts, and as promastigotes in invertebrate hosts and in cultures. Species are largely indistinguishable morphologically but may be distinguished by clinical manifestations, geographic distribution and epidemiology, developmental patterns of promastigotes in their sandfly hosts, virulence testing of clones in vivo, the effect of test sera on growth in culture, cross-immunity tests, and serotyping with promastigote excreted factors; strains also can be distinguished by various biochemical analyses and DNA sequencing. Such procedures have identified all recognized groups and confirmed the separation of New World leishmaniasis agents into two species complexes, Leishmania mexicana and Leishmania braziliensis.
[W. B. Leishman]

Leishmania

/Leish·ma·nia/ (lēsh-ma´ne-ah) a genus of parasitic protozoa, including several species pathogenic for humans. In some classifications, organisms are placed in four complexes comprising species and subspecies: L. donova´ni (causing visceral leishmaniasis), L. tro´pica (causing the Old World form of cutaneous leishmaniasis), L. mexica´na (causing the New World form of cutaneous leishmaniasis), and L. vian´nia (causing mucocutaneous leishmaniasis).

Leishmania

[lēshmā′nē·ə]
Etymology: William B. Leishman
a genus of protozoan parasites. These organisms are transmitted to humans by any of several species of sand flies.

Leish·man·i·a

(lēsh-man'ē-ă)
A genus of digenetic, asexual, protozoan flagellates that occur as amastigotes in the macrophages of vertebrate hosts, and as promastigotes in invertebrate hosts and in cultures.
[W. B. Leishman]

leish·man·i·a

, pl. leishmaniae (lēsh-man'ē-ă, -ē)
A member of the genus Leishmania.

Leishmania

A genus of single-celled organisms equipped with a whip-like motility organ (flagellated protozoon). The genus contains many species responsible for the various forms of LEISHMANIASIS, known by such names as KALA AZAR, ESPUNDIA, forest yaws, chiclero ulcer, uta, diffuse cutaneous Leishmaniasis, oriental sore, Aleppo boil, Baghdad boil, bouton d'Orient and Delhi boil.

Leishman,

Sir William Boog, Scottish surgeon, 1865-1926.
Leishmania - a genus of digenetic, asexual, protozoan flagellates.
Leishman chrome cells - basophilic granular leukocytes (basophils) observed in the circulating blood of some persons with blackwater fever.
Leishman stain - a polychromed eosin-methylene blue stain used in the examination of blood films.
Leishman-Donovan body - the intracytoplasmic, nonflagellated leishmanial form of certain intracellular parasites. Synonym(s): amastigote; L-D body
leishmaniasis - tropical disease that is spread by sandflies.

Leishmania

a genus of protozoan parasites transmitted by sandflies, which also act as intermediate hosts.

Leishmania adleri
found in lizards and other mammals.
Leishmania aethiopica
reservoir hosts are hyraxes.
Leishmania brasiliensis brasiliensis
reservoir hosts are forest rodents. Causes mucocutaneous leishmaniasis in humans.
Leishmania brasiliensis guyanensis
dogs are infected; in humans the disease is the cutaneous form in most cases.
Leishmania brasiliensis panamensis
reservoirs are sloths, kinkajous and many other forest animals.
Leishmania chagasi
causes visceral leishmaniasis in humans and dogs.
Leishmania donovani
causes visceral leishmaniasis in humans and in carnivores.
Leishmania enriettii
causes cutaneous leishmaniasis in guinea pigs.
Leishmania infantum
causes visceral leishmaniasis in dogs and other carnivores. In humans it is children who are most commonly affected.
Leishmania major
dogs and bush mammals are reservoir hosts. In humans this is the cause of oriental sore, the important cutaneous form of the disease.
Leishmania mexicana amazonensis
causes cutaneous leishmaniasis in humans. Rodents and bush animals are reservoir hosts.
Leishmania mexicana mexicana
reservoir hosts are rodents; causes cutaneous leishmaniasis in humans.
Leishmania mexicana pifanoi
causes chronic cutaneous leishmaniasis in humans.
Leishmania peruviana
causes cutaneous leishmaniasis in humans; probably infests dogs.
Leishmania tropica
causes cutaneous leishmaniasis in humans and dogs.
References in periodicals archive ?
La leishmaniosis visceral (LV) es una enfermedad cronica zoonotica del canino causada por un protozoario del genero Leishmania.
Disseminated leishmaniasis by Leishmania viannia subgenus: a series of 18 cases in southeastern Brazil.
Estas vacunas han sido preparadas con Leishmania amazonensis y/o Leishmania major, lisadas por autoclave y con adyuvante de Freund completo (13, 14), o mediante la mezcla de promastigotos de Leishmania mexicana sometidos al autoclave y BCG (Bacilo de Calmette-Guerin).
Live Leishmania promastigotes can directly actiate primary human natural killer cells to produce interferon-gamma.
Leishmania typing: The ribosomal internal transcribed spacer 1 (ITS1) was subjected to PCR, using the LITSR and L.
Of the 100 patients clinically suspected to be infected by Leishmania parasites, 60 (60%) were male.
This patient had no evidence of immune deficiency, nor had one manifest during the follow-up period after her illness, yet she had a negative rK39 test result (which detects Leishmania antibodies) despite a visceral infection.
Previously established Leishmania genus primer and probe sequences were obtained from the literature for LEIS freeze-dried assay development.
Percentage inhibition of Leishmania promastigotes were calculated by using following formula:
In a study conducted by Mirzae et al, (14) approximately one-third of the rodents captured from the deserts in Fars Province and Turkmen Sahra tested positive for Leishmania, with L.
In 1-10% of patients, leishmania disseminates from the skin to the nasooropharyngeal mucosa, resulting in mucosal leishmaniasis (ML) and destruction of nasal and pharyngeal structures.