1. بسم الله الرحمن الرحیم

2. Kingdom protista (classification of protozoa)
Subk.: Protozoa
phylum: Apicomplexa Ciliophora Sarcomstigophora Microspora
Subph: Sarcodina Mastigophora
(Amebae) (Flagellates)
Parasitic Amebae Free-living Amebae
Family: Endamoebidae Leptomyxidae Acanthamoebidae Vahlkampfidae
Genus: Entamoeba Iodamoeba Endolimax
gingivalis butschlii nana
Sp Hartmani
histolytica
coli
dispare

3. Entamoeba gingivalis (non-pathogen)
-Prevalance rate
- Live site
- Morphology
- cytoplasm
Diagnosis: may be mistaken for E.histolytica from a pulmonary abscess

4. Entamoeba coli (non-pathogen)
Prevalance: 1 to 50%
Morphology: trophozoite range 15-50µm
( very closely resemble E.histolytica)
- cytoplasm
- Pseudopodia
Motility
*nucleus
*karyosome
*peripheral chromatin

5. Entamoeba hartmani
*small race of E.histolytica (morphologic similarity)
*size: trophozoite < 12 mμ , c yst < 10 mμ
*only clear-cut distinction between the two species is size
*trophozoite ingest bacteria but no RBC

6. Entamoeba dispare : Iodamoeba butschlii :
*There is no morphologic differences between this amoeba with E.histolytica *This amoeba no ingest RBC
Iodamoeba butschlii :
*Trophozoite size(4-20μm), cytoplasm may be contain bacteria, large karyosome, small granules
*Cyst size(9-10 μm): contain glycogen vacuole, sigle nuclei

7. Endolimax nana *most common of the smaller intestinal amaeba
*Size: trophpozoite and cyst is similar to theat of E.hartmani
*Motility: sluggish
pseudopodia extruded rapidly
*Cytoplasm:
Nucleus: contain large karyosome
*Cyst:

8. Free-Living Amebae (Opp0rtuistic Amebae)
Family: Vahlkampfiidae Acathamoebidae Leptomyxidae
Genus: Naegleria Acanthamoeba Balamuthia
Species: fowleri castellani mandrillaris
calbertsoni
polyphaga
Habitat: in fresh, brackish and salt water, moist soil and decaying vegetation
History: Human infection were first reported by Fowler in 1965
Geographic distribution: The most cases were reported from; USA, Australia, Czech, Oslovakia, Belgium, India,……..
Epidemiology: Most cases have occurred during summer in young persons who swam or dived in swimming pools and during the ritual washing before prayer

9. Naegleria fowleri Morphology , Biology and Life cycle: flagellate form
*Life cycle stage consist: -motile trophozoite:
-nonmotile cysts ameboid form
*Reproduction: simple binary fission
*Ameboid form: found in tissue , forms a single pseudopod,
dimensions 7 by 20μm, With a nucleus contain a large central karyosome
*Flagellate form: with two flagella, pear-shaped, do not divided
*Cyst form: uninucleate, circular 7-10μm in diameter, nucleus is similar to troph.

10. Naegleria forms

11. Naegleria cyst & trophozoite

12. Life cycle

13. Symptoms and pathogeesis
Primary Amebic Meningoencephalitis(P.A.M.) :
Symptoms; headache, fever, nausea
and vomiting accompanied by signs
of meningitis with involvement of the
olfactory, frontal, temporal, and
cerebral areas
Death : occurs early; the entire
clinical course seldom extends
beyond 3 to 6 days.

14. Acanthamoeba( Hartmanella) spp.
Morhology, Biology and Life cycle:
These amebae are similar in appearance to the ameboid stage of Naegleria but have no flagellate stage.
Cyst & Trophozoite may be found in tissue, but cysts are never seen in Naegleria infections.
Pseudopods are acanth forms

15. Acanthamoeba trophozoite

16. Free-living Amebae Life Cycle

17. Symptoms & Pathogenesis
Granulomatous Amebic Encephalitis( GAE):
*Invasion of the CNS is not associated with swimming but is secondary to infection elsewhere in the body .
Amebae reach the brain by way of blood stream, likely from lung or through ulcer the skin or mucosa
Occurs most often in debilitated or immunocompromised persons
A. astronyxis and A. palestinensis associated only with CNS infection
Acanthamoeba Keratitis:
* Affects healthy person, increase in the number of cases in the recent years has been linked to the wearing of contact lenses, especially soft ones.
A. polyphaga and A.hatchetti only with eye infection.
Chronic granulomatous infection of the skin
A. castellani, A. culbertsoni ,….. Have causea both CNS and eye infections

19. Keratitis

20. Diagnosis of PAM and GAE:
Diagnosis of PAM and GAE: *A patient’s history of having been swimming in water 3 to 6 days prior to onset of symptoms of PAM suggest a possible diagnosis. * In brain tisse is made by microscopic identification of living or Wright-stained amebae in the patient’s CSF or trophozoites and cysts of Acanth.. * by cultivation of cerebrospinal fluid in medium non-nutrient agar seeded with living Escherichia coli for PAM and corneal scraping cultured for Acanth. Keratitis.
Treatment: At present there is no satisfactory treatment fir PAM and GAE.
*Amphotericin B, is administered intravenously in large doses; 1 to 1.5 mģ/kg body weight daily for 3 days, followed by 1 mg/kg daily for 6 days.
*Miconazole and Rifampin are other alternative drugs.