Leishmaniasis made easy for you. by R.Banda.ppt

Leishmaniasis is a vector-borne disease that is transmitted by sandflies and caused by obligate intracellular protozoa of the genus Leishmania.

1. LEISHMANIASIS
Mr. R.BANDA
COG
Medical Parasitology

2. Leishmaniasis is an infection with Leishmania, a group of Trypanosomatid Parasitic Protozoa.
Leishmania parasites are found in tropical and subtropical areas of the world. It can cause severe
ulcers on your skin (cutaneous leishmaniasis) or infection of your internal organs that can be fatal
(visceral leishmaniasis). Anti-parasitic medications treat leishmaniasis.
Spread from a bite by a sandfly of the genus;
Phlebotomus in the old world
Lutzomyia in the new world.
It’s one of the second largest parasitic killers in the world after Malaria and is endemic in many parts
of Africa, Asia and South America.
IntroductionIntroduction

3. KINGDOM Protista
SUBKINGDOM Sarcomastigophora
PHYLUM Protozoa
SUBPHYLUM Masigophora
CLASS Zoomastigophora
ORDER Kinetplastida
GENUS Leishmania
SPECIES Donovani, Tropica, Mexicana, Major, Guyanensis, Lainsoni e.t.c
ClassificationClassification

4. Essentially parasites of visceral organs;
Promastigotes forms found in sand flies and in cultures
Amastigote forms found in man in Reticuloendothelial cells of
Spleen
Liver
Bone Marrow
Intestinal Mucosa
Mesenteric Lymph nodes
HabitatHabitat
(L. Donovani)(L. Donovani)

5. Morphological
Differences
Amastigotes Promastigotes
Aflagellar Stage Flagella Stage
Occurs in the Vertebrate host Occurs in the Sand Fly
Divides by Binary Fission@37c Divides by Binary Fission @ 27c
There are round/oval, 2-4mm Along
Longitudinal Axis
They are spindle shaped, 15-20mm in
length and 1-2mm in widith
Nucleus relatively larger and situated
centrally
Nucleus smaller and situated in the
middle of the cell/ along the side of the
cell wall.

7. Life CycleLife Cycle

8. Leishmaniasis is transmitted by the bite of infected female phlebotomine sandflies. The sandflies inject
the infective stage (i.e., promastigotes) from their proboscis during blood meals
Promastigotes that reach the puncture wound are phagocytized by macrophages
and other types of mononuclear phagocytic cells. Promastigotes transform in these cells into the tissue
stage of the parasite (i.e., amastigotes), these multiply by simple division and proceed to infect other
mononuclear phagocytic cells.
Parasite, host, and other factors affect whether the infection becomes symptomatic and whether
cutaneous or visceral leishmaniasis results. Sandflies become infected by ingesting infected cells
during blood meals.
In sandflies, amastigotes transform into promastigotes, develop in the gut
 

     
 
(in the hindgut for
leishmanial organisms in the
 Viannia subgenus; in the midgut for organisms in
the
 Leishmania subgenus), and migrate to the proboscis

Life CycleLife Cycle

9. TypesTypes
Leishmaniasis falls into three main categories
 cutaneous,
mucosal (or mucocutaneous)
visceral.
Cutaneous leishmaniasis
Cutaneous leishmaniasis (CL) is an infection in your skin where a sand fly bit you. It causes bumps
(nodules) that turn into large ulcers over time. It can take a long time to heal on its own. Symptoms start a
few weeks or months after a sand fly bite.
Very rarely, you can have bumps or ulcers on many areas of your skin (diffuse cutaneous leishmaniasis).
These can come back again and again (recur), even with treatment.
Mucosal (mucocutaneous) leishmaniasis
Mucosal, or mucocutaneous leishmaniasis (ML), is usually a complication of cutaneous leishmaniasis.
Ulcers develop in your nose, mouth or throat (mucous membranes). ML rarely gets better on its own and is
usually fatal if left untreated. It can cause facial disfigurement.
Visceral leishmaniasis (VL)
Visceral leishmaniasis (VL), also called kala-azar, is a serious form of the disease caused by specific types
of
 Leishmania. It affects your internal organs, like your spleen and liver. Symptoms sometimes take a few
months or a year or more to develop after an infected fly bites you. VL can cause severe disease quickly.
It’s fatal if left untreated.

10. Clinical PresentationsClinical Presentations
Symptoms of leishmaniasis depend on what type you have. Cutaneous and mucosal leishmaniasis
cause large, slow-healing ulcers. Visceral leishmaniasis causes general symptoms, like fever,
weight loss and abdominal swelling.
Other
Fever
Sleenomegally
Lymphadenopathy
Darkening of the skin (Black Fever)
Complications
Pneumonia
TB
Dysentery
Uncontrolled Hemorrhage
Prognosis: With an early treatment, cure rate >90% while if not treated, death occurs within 2yrs.

11. Investigations
Direct Evidences:
Thick Film method
Blood cultures
Biopsy
Indirect Evidences
Blood Count
Serum Tests
Other Methods
Animal Inoculation
Leishmanin or Montengeno Test
Adlers Test

12. Treatment
Sodium Stibogluconate Solution: Inhibits glycolytic enzymes and fatty acid
oxidation
Amphotericin B: Binds with ergosterol leading to the altered permeability to
cations, water, glucose and affect membrane-bound enzymes.
Pentamidine: Inhibits DHFR and Interferes with aerobic glycolysis in protozoa
also inhibits protein synthesis
Miltefosine: Effects cell signaling pathways and synthesis of the cell-membrane
Interferon: Macrophage activation.

13. Prevention & Control
1.Reduction of sand fly populations
Insecticides mainly malathion
2.Reduction of Reservoir
1.Killing all infected dogs in the cases of zoonotic kala-azar
3.Education in the Community
1.O the causes and modes of transmission
•Prevention of exposure to sand fly
1.Using insect repellants, bed nets and window mess.
NB: Leishmaniasis has no vaccine