Medical biology

1. Medical biology
By Abdulsattar Aswed
Master in medical Microbiology
Entamoeba
gingivalis and
giardia lamblia

2. Entamoeba coli
The trophozoite of Entamoeba coli typically measure between 18 and 27
μm . Some trophozoites may be as small as 12 μm , while others may be
as large as 55 μm . red blood cell inclusions do not occur .

3. Entamoeba coli

6. Life cycle
Life cycle of E. coli is similar to E. histolytica life cycle
with the exception of difference in cyst nucleus
numbers

7. Clinical symptoms
Infections with E. coli are usually asymptomatic

9. Entamoeba coli trophozoite

10. Entamoeba coli cyst

11. Entamoeba gingivalis
Is an opportunistic Amoebozoa (reported by some to
cause disease) and is the first amoeba in humans to be
described.
Entamoeba gingivalis

12. Trophozoite

13. • The trophozoite of Entamoeba gingvalis ranges in size from 8
to 20 μm and morphologically resembles that of E. histolytica
Entamoeba gingivalis trophzoites characteristically exhibit
active motility .
• E. gingivalis is the only ameba that ingests white blood cells .
This distinguishing characteristic is helpful when it is
necessary to differentiate E. gingivalis from E. histolytica .
What the differences between Entamoeba gingvalis and E.
histolytica ?

14. Life cycle

15. Clinical symptoms
Clinical symptoms
Infections of E. gingivalis occurring both in the
mouth and in the genital tract typically produce
no symptoms. Nonpathogenic E. gingivalis
trophozoites are frequently recovered in-patients
suffering from pyorrhea alveolaris.

16. Entamoeba gingvalis trophozoite

17. Entamoeba gingvalis trophozoite

18. Giardia lamblia

19. Giardia lamblia trophozoite : Typical characteristics
Size range 8 to 20 μm long
5 to 16 μm wide
Shape Pear / tear drop
Motility “ Falling leaf “
Appearance Bilaterally symmetrical
Nuclei Two ovoid – shaped , each with a large karyosome
No peripheral cromatin
Flagella Four pair , origination of each :
One pair anterior end
One pair posterior end
Two pair central laterally
Other structures Two median bodyies , two axonemes , sucking disc

21. Giardia lamblia cyst : Typical characteristics
Size range 8 to 17 μm long
6 to 10μm wide
Shape Ovoid
Nuclei Immature cyst – 2
Mature cyst – 4
Central karyosomes
No peripheral chromatin
Cytoplasm Retracted from cell wall
Other structures Median bodies , two or four
Interior flagellar structures

28. Life
cycle

30. Giardiasis (“Traveler’s
Diarrhea)
Clinical symptoms
mild
diarrhea
anorexia
malabsorption
syndrome
abdominal
cramps

32. Laboratory diagnosis

33. Giardia lamblia trophozoite

34. Giardia lamblia trophozoite

35. Giardia lamblia cyst

36. Giardia lamblia cyst

37. Thanks for listening