Leishmaniasis 1 Leishmaniasis Species Pathogenic in Humans Leishmania

Leishmaniasis 1

Leishmaniasis Species Pathogenic in Humans Leishmania donovani (complex) (VL) Leishmania tropica (CL) Leishmania major (CL) Leishmania aethiopica (CL) Leishmania mexicana (Complex) (CL) Leishmania brazilliensis (complex) (MCL) 2

The Parasite • Phylum Sarcomastigophora • Order Kinetoplastida • Family Trypanosomatidae • Genus Leishmania 3

Morphology Digenetic Life Cycle • Promasitogte • Insect • Motile • Midgut • Amastigote • Mammalian stage • Non-motile • Intracellular 4

Morphology • Promastigote • Amastigote Flagella Kinetoplast Golgi Nucleus Cytoskeleton 5

Promastigote 6

Amastigote 7

• Leishmania (Leishman. Donovan or LD bodies). Lying in macrophage cells from liver. Giemsa. × 12000. Enlarged by 9. 6. 8

• A macrophage filled with Leishmania amastigotes. 9

Life cycle • The organism is transmitted by the bite of several species of blood-feeding sand flies (Phlebotomus) which carries the promastigote in the anterior gut and pharynx • Dogs and rodents are common reservoirs. 10

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Mammalian Hosts • Rodents • Bats • Dogs • Foxes 12

Vectors Phlebotomine Sandflies 13

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Clinical Disease • Visceral • Fatal (90% untreated) • Liver • Spleen • Bone marrow • Cutaneous • Generally Self- healing • Skin • Mucous membranes SPECTRUM OF DISEASE 15

Initial Infection • • Similar in all species Inoculation of promastigotes Inflammation & chemotaxis Receptor mediated phagocytosis Promastigote Amasitgote Transformation 16

Parasite Spread Macrophage lysis & parasite release Lymphatic spread Blood spread Target organs Skin/lymph nodes/spleen/liver/ bone marrow 17

Clinical Manifestation Variable - Incubation 3 -100+ weeks Lowgrade fever Hepato-splenomegaly Bone marrow hyperplasia Anemia, Leucopenia & Cachexia Hypergammaglobulinnemia Epistaxis , Proteinuria, Hematuria 18

• A boy suffering from visceral leishmaniasis. The boy exhibits splenomegaly, distended abdomen and severe muscle wasting. 19

• Jaundiced hands of a visceral leishmaniasis patient. 20

• Enlarged spleen and liver in an autopsy of an infant dying of visceral leishmaniasis. 21

Post Kala Azar Dermal Leishmanoid Normally develops <2 years after recovery Recrudescence Restricted to skin Rare but varies geographically 22

Cutaneous leishmaniasis of the face. 23

A cutaneous leishmaniasis lesion on the arm. 24

INFECTION Sub-clinical or inapparent infection Recovery Death Immune to reinfection Concurrent infection PKDL 25

Diagnosis Bone marrow biopsy Spleen or liver biopsy Culture & Histology 26

Treatment Pentavalent antimony Pentamidine New drugs - New delivery 27