leishmania features

1. Leishmania

2. Leishmania
• There are three Leishmania species which
are parasite in man, L. donovani, L. tropica
& L. brasiliensis.
• There is not much morphological difference
in these three species.

3. Leishmania donovani
• Geographical Distribution
1. It is endemic in many places in America, Africa,
China, South Europe and India .
2. In India it is common in Assam, Bengal, Orissa,
Tamil Nadu and eastern parts of Uttar Pradesh
upto Lucknow

4. Habitat
• Reticuloendothelial system especially
spleen, liver, bone marrow, intestinal
mucosa.
• Endothelial cells of kidneys, lungs,
meninges, CSF, macrophages of intestinal
wall

5. Leishmania Parasites and Diseases
DiseaseSPECIES
Cutaneous leishmaniasis
Leishmania tropica*
Leishmania major*
Leishmania aethiopica
Leishmania mexicana
Mucocutaneous leishmaniasisLeishmania braziliensis
Visceral leishmaniasis
Leishmania donovani*
Leishmania infantum*
Leishmania chagasi

6. Morphology
• Exists in two forms:
1. Leishmanial/Amastigote form/Aflagellar Stage/:
• It is found as an intracellular parasite in the cell of
endothelial system.
• It is round in shape, the blepharoplast and
parabasal body are situated at right angles to the
nucleus.
• From the blepharoplast, a delicate filament
axoneme extends representing the root of the
flagellum.
• Alongside the axoneme is a clear space vacuole.

7. Amastigote form

8. 2. Leptomonad /Promastigote form/Flagellar
Stage:
• It is found only in the insect vector Sand Fly.
• The undeveloped forms are small and pear shaped
while the developed forms are long and spindle
shaped.
• Blepharoplast and parabasal body are situated in
front of the nucleus.
• Along flagellum sometimes longer than the body
arises from the blepharoplast.

10. Mode of Transmission
• Bite of sandfly (Phlebotomus)
• Mother to fetus
• Blood transfusion
• Accidental inoculation of culture in the
laboratory

11. 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.
• It gains access to mononuclear phagocytes where it
transform into amastogotes and divides until the infected
cell ruptures.
• The released organisms infect other cells. The sandfly
acquires the organisms during the blood meal, the
amastigotes transform into flagellate promastigotes and
multiply in the gut until the anterior gut and pharynx are
packed.
• Dogs and rodents are common reservoirs.

13. Sand fly

14. Clinical Types Of Cutaneous Leishmaniasis
• Leishmania major: Zoonotic cutaneous
leishmaniasis: wet lesions with severe reaction
• Leishmania tropica: Anthroponotic cutaneous
leishmaniasis: Dry lesions with minimal ulceration
Oriental sore (most common) classical self-
limited ulcer

16. Uncommon types
• Diffuse cutaneous leishmaniasis (DCL):
Caused by L. aethiopica, diffuse nodular non-
ulcerating lesions. Low immunity to Leishmania
antigens, numerous parasites.
• Leishmaniasis recidiva (lupoid leishmaniasis):
Severe immunological reaction to leishmania
antigen leading to persistent dry skin lesions, few
parasites.

17. Diffuse cutaneous leishmaniasis
Leishmaniasis recidiva

18. Cutaneous Leishmaniasis
Diagnosis:
• Smear: Giemsa stain – microscopy for LD
bodies (amastigotes)
• Biopsy: microscopy for LD bodies or culture
in NNN medium for promastigotes

19. Treatment
• No treatment – self-healing lesions
• Medical:
o Pentavalent antimony (Pentostam), Amphotericin B
o +/- Antibiotics for secondary bacterial infection.
• Surgical:
o Cryosurgery
o Excision
o Curettage

20. Visceral leishmaniasis
• There are geographical variations.
• The diseases is called kala-azar
• Leishmania infantum mainly affect children
• Leishmania donovani mainly affects adults

21. Presentation
• Fever
• Splenomegaly, hepatomegaly, hepatosplenomegaly
• Weight loss
• Anaemia
• Epistaxis
• Cough
• Diarrhoea
• Untreated disease can be fatal
• After recovery it might produce a condition called
post kala-azar dermal leishmaniasis (PKDL)

22. Untreated disease can be fatal
After recovery it might produce a condition
called post kala-azar dermal leishmaniasis
(PKDL)

23. hepatosplenomegaly

24. mucocutaneous

25. PKDL

26. Visceral leishmaniasis
Diagnosis
(1) Parasitological diagnosis: METHOD
Bone marrow aspirate 1. microscopy
Splenic aspirate 2. Culture
Lymph node
Tissue biopsy

27. (2) Immunological Diagnosis:
• Specific serologic tests: Direct Agglutination
Test (DAT), ELISA, IFAT
• Skin test (leishmanin test) for survey of
populations and follow-up after treatment.

28. Treatment:
• Pentavalent antimony (Pentostam)
• Amphotericin B
Treatment of complications:
• Anaemia
• Bleeding
• Infections etc.