2. What is Leishmaniasis?
Leishmaniasis is a disease caused
by protozoan parasites that belong
to the genus Leishmania.
Disease is transmitted by the bite of
certain species of sand fly.
3. Systematic position of
Leishmania spp.
Eukaryota (organisms with nucleated cells),
Kingdom :Protista,
Phylum :Protozoa,
Class :Flagellates,
Genus :Leishmania.
From genus Leishmania about 21 species
infect human. 3species are the most
important:
1- L.donovani (Visceral
Leishmaniasis“Kalaazar”).
2- L. Tropica (Cutaneous Leishmaniasis
“orientalsore”).
3- L.braziliensis (Muco-cutaneous
4. Vector of Leishmaniasis
Leishmania is transmitted by certain
species of sand fly, including flies in
the genus Lutzomyia and
Phlebotomus.
6. Disease Transmission
1- Through the bite of infected
sand fly.
2- By direct contact with infected
material from the lesion of an
infected person.
7. Clinical Features
Human leishmanial infections can
result in 3 main forms of disease:
◦ cutaneous leishmaniasis (oriental sore),
◦ visceral leishmaniasis (kala-azar),
◦ Mucocutaneous Leishmaniasis
(Espundia).
The factors determining the form of
disease include:
◦ leishmanial species,
◦ geographic location,
◦ immune response of the host.
8. Cutaneous leishmaniasis
Cutaneous leishmaniasis is
characterized by:
1- one or more cutaneous lesions on areas
where sandflies have fed.
2- Persons who have cutaneous leishmaniasis
have one or more sores on their skin.
3- The sores can change in size and appearance
over time.
4- They often end up looking somewhat like a
volcano, with a raised edge and central crater.
5- A scab covers some sores.
6- The sores can be painless or painful.
11. Visceral Leishmaniasis
Persons who have visceral
leishmaniasis usually have:
1- Fever.
2- Weight loss.
3- Enlarged spleen and liver (usually the
spleen is bigger than the liver).
4- Low blood counts, including a low red
blood cell count (anemia), low white blood
cell count (leukopenia), and low platelet
count.
13. Diagnosis of Leishmaniasis
Clinically :
1- Fever
2- Enlargement of liver and spleen.
3- Anaemia & leukopenia.
4- By the picture of sore.
14. Laboratory
diagnosis
- Clinical signs and symptoms
- Scrapings from the side or edge of the lesion in
case of cutaneous leishmaniasis and material
aspirated from the spleen, bone marrow or enlarged
lymph glands and peripheral blood monocytes in
case of visceral leishmaniasis for demonstration of
amastigotes by light microscopy with Wright or
Giemsa stain
- Isolation, visualization, and culturing of the
parasite from infected tissue
15. - Serologic detection of antibodies to
Leishmania that may be present in patient’s
serum - Polymerase chain reaction (PCR)
assay for sensitive and rapid diagnosis of
Leishmania species
- Leishmanin (Montenegro) skin testing (LST)
5
- It is an intradermal test for delayed
hypersensitivity.
- Most reliable for cutaneous leishmaniasis. A
suspension of 107/ml promastigotes in 0.5%
phenol/saline given intradermally. Test is read
after 2~3 days.
Positive test included erythema and induration
