1 leishmaniasis leishmania donovani (complex) (vl) leishmania tropica (cl) leishmania major (cl)...
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Leishmaniasis Leishmaniasis
Leishmania donovani (complex)Leishmania donovani (complex) (VL) (VL)
Leishmania tropica (CL)Leishmania tropica (CL)
Leishmania major (CL)Leishmania major (CL)
Leishmania aethiopica (CL)Leishmania aethiopica (CL)
Leishmania mexicana (Complex) (CL)Leishmania mexicana (Complex) (CL)
Leishmania brazilliensis (complex) (MCL)Leishmania brazilliensis (complex) (MCL)
Leishmania perurianaLeishmania peruriana
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The ParasiteThe Parasite
• PhylumPhylum
• OrderOrder
• FamilyFamily
• GenusGenus
SarcomastigophoraSarcomastigophora
KinetoplastidaKinetoplastida
TrypanosomatidaeTrypanosomatidae
LeishmaniaLeishmania
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MorphologyMorphology
• PromasitogtePromasitogte• InsectInsect• MotileMotile• MidgutMidgut
• AmastigoteAmastigote• Mammalian stageMammalian stage• Non-motileNon-motile• IntracellularIntracellular
Digenetic Life CycleDigenetic Life Cycle
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MorphologyMorphology
• Promastigote • Amastigote
Flagella
Kinetoplast
Golgi
Nucleus
Cytoskeleton
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Promastigote
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• Amastigotes (*) of Leishmania donovani in the cells of a spleen. The individual amastigotes measure approximately 1 µm in diameter.
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Amastigote
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• Amastigotes of Leishmania in a macrophage from a lymph node of a dog.
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• Leishmania (Leishman-Donovan or LD bodies). Lying in macrophage cells from liver. Giemsa. ×12000. Enlarged by 9.6.
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• A macrophage filled with Leishmania amastigotes.
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Life cycleLife cycle
• The organism is transmitted by the bite of several The organism is transmitted by the bite of several species of blood-feeding sand flies (Phlebotomus) species of blood-feeding sand flies (Phlebotomus) which carries the promastigote in the anterior gut and which carries the promastigote in the anterior gut and pharynx. It gains access to mononuclear phagocytes pharynx. It gains access to mononuclear phagocytes where it transform into amastogotes and divides until where it transform into amastogotes and divides until the infected cell ruptures. The released organisms the infected cell ruptures. The released organisms infect other cells. The sandfly acquires the organisms infect other cells. The sandfly acquires the organisms during the blood meal, the amastigotes transform into during the blood meal, the amastigotes transform into flagellate promastigotes and multiply in the gut until flagellate promastigotes and multiply in the gut until the anterior gut and pharynx are packed. Dogs and the anterior gut and pharynx are packed. Dogs and rodents are common reservoirs.rodents are common reservoirs.
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Mammalian HostsMammalian Hosts
• RodentsRodents• GerbilsGerbils• HyraxesHyraxes• BatsBats• PorcupinesPorcupines• OpossumsOpossums
• SlothsSloths• PrimatesPrimates• DogsDogs• FoxesFoxes• AnteatersAnteaters• . . . .. . . . .
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VectorsVectors
Phlebotomine SandfliesPhlebotomine Sandflies
6 genera world wide distribution6 genera world wide distribution
Phlebotomus & LutzomiaPhlebotomus & Lutzomia
500 species500 species
Females HaematophagusFemales Haematophagus
Males sap feedersMales sap feeders
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Clinical Disease
• Visceral• Fatal (90%
untreated)• Liver• Spleen• Bone marrow
• Cutaneous• Generally Self- healing • Skin• Mucous membranes
SPECTRUM OF DISEASE
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Initial Infection
• Similar in all species• Inoculation of promastigotes• Inflammation & chemotaxis• Receptor mediated phagocytosis
Promastigote Amasitgote Transformation
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Parasite SpreadParasite Spread
Macrophage lysis & parasite releaseMacrophage lysis & parasite release
Lymphatic spreadLymphatic spread
Blood spreadBlood spread
Target organsTarget organs
Skin/lymph nodes/spleen/liver/Skin/lymph nodes/spleen/liver/
bone marrowbone marrow
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Visceral LeishmaniasisVisceral Leishmaniasis
• 19031903• 19201920• 19311931
William LeishmanWilliam Leishman
Pentavalent antimonyPentavalent antimony
Experimental transmissionExperimental transmission
Leishmania donovani (Complex)Leishmania donovani (Complex)
L.d. archibaldi - L.d.chagasi - L.d.donovani - Ld.infantumL.d. archibaldi - L.d.chagasi - L.d.donovani - Ld.infantum
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VL - Clinical ManifestationVL - Clinical Manifestation
Variable - Incubation 3-100+ weeksVariable - Incubation 3-100+ weeks
Lowgrade feverLowgrade fever
Hepato-splenomegalyHepato-splenomegaly
Bone marrow hyperplasiaBone marrow hyperplasia
Anemia, Leucopenia & CachexiaAnemia, Leucopenia & Cachexia
HypergammaglobulinnemiaHypergammaglobulinnemia
Epistaxis , Proteinuria, HematuriaEpistaxis , Proteinuria, Hematuria
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• Profile view of a teenage boy suffering from visceral leishmaniasis. The boy exhibits splenomegaly, distended abdomen and severe muscle wasting.
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• A 12-year-old boy suffering from visceral leishmaniasis. The boy exhibits splenomegaly and severe muscle wasting.
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• Jaundiced hands of a visceral leishmaniasis patient.
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• Enlarged spleen and liver in an autopsy of an infant dying of visceral leishmaniasis.
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Post Kala Azar Dermal Post Kala Azar Dermal LeishmanoidLeishmanoid
Normally develops <2 years after Normally develops <2 years after recoveryrecovery
RecrudescenceRecrudescence
Restricted to skinRestricted to skin
Rare but varies geographicallyRare but varies geographically
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Cutaneous leishmaniasis of the face.
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A cutaneous leishmaniasis lesion on the arm.
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INFECTIONINFECTION
Sub-clinical or inapparent infectionSub-clinical or inapparent infection
Recovery DeathImmune to reinfection Concurrent infection
PKDL
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DiagnosisDiagnosis
Clinical signs & symptomsClinical signs & symptoms
HypergammaglobulinemiaHypergammaglobulinemiaELISA/Formol gelELISA/Formol gel
Bone marrow biopsyBone marrow biopsy
Spleen or liver biopsySpleen or liver biopsy
Culture & HistologyCulture & Histology
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SpeciationSpeciation
• Similar morphologySimilar morphology• Isoenzyme profiles - ZymodemesIsoenzyme profiles - Zymodemes• Monoclonal antibodiesMonoclonal antibodies• DNA hybridisation - PCRDNA hybridisation - PCR
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TreatmentTreatment
Good nursingGood nursing
DietDiet
AntibioticsAntibiotics
Pentavalent antimonyPentavalent antimony
PentamidinePentamidine
New drugs - New deliveryNew drugs - New delivery
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ControlControl
• Vector controlVector control• Reservoir controlReservoir control• Treatment of active casesTreatment of active cases• VaccinationVaccination