amoebiasis is a very important topic for pg entrance........so every important point about it have been discussed in detail......take a look at it...

1. -DR.AKIF A.B

2. -Infective and diagnostic form = Quadrinucleate cyst
-Flask shaped intestinal ulcer
-MC site: Ileo-caecal region

4. TRANSVERSE ULCER

5. -MC site : Liver
- MC site involved: Postero- superior surface of right lobe of liver
-Anchovy sauce pus
-Rupture can lead to Pleural effusion/Ascites

7. -Stool microscopy : If shows
1) Trophozoite : Indicates active infection
2) cyst : Indicates carrier state
-Charcot Leydin crystals in stool
-Leucocytosis in blood
-Culture : Gold standard

9. TROPHOZOITE ENTAMOEBA
HISTOLYTICA
ENTAMOEBA COLI
Size 15-25 microns 20-25 microns
Motility very active, unidirectional
purposeful motility.
Sluggish, non purposeful,
aimless motility
Cytoplasm Differentiated into
ectoplasm and endoplasm
Not differnetiated
Cytoplasm has RBCs, WBCs, tissue debris
and bacteria
No RBCs
Cyst 1-4nuclei 1-8nuclei

10. 1)Q. Amoebae not found in human intestine:
A E.Histolytica
B E.Coli
C E.Nana
DGingivalis

11. D) Gingivalis
E. Gingivalis is found in oral cavity.
E.Coli and E. Nana are non-pathogenic amoebae.

12. 2)Q.Cyst of Entamoeba histolytica how many nuclei?
A 1-2
B 1-4
C 1-6
D 1-8

13. B) 1-4
a. Cyst of E. Histolytica contains 1-4 nuclei. It is the
infectious form for Entamoeba histolytica.
b. It is 10-15 micron. Spherical and quadrinucleate.
c. Thick chitinous wall which makes it resistant to gastric acid
and chlorine in water.
d. Uninucleate and binucleate have a glycogen mass (stains
brown with iodine) and 1-4 chromatoid bars (stains black
with iron-hematoxylin).

14. 3.Q. Pseudopodia is mode of locomotion in
A Entamoeba histolytica
B Candida
C Mycoplasma
D Treponema pallidum

15. Ans. A Entamoeba histolytica
a. Pseudopodia are found in E. Histolytica. Other protozoa
pathogenic to humans which are motile by protozoa are
Acanthamoeba and Naeglaria.
b. Treponema pallidum is a bacterium motile by flagella on the
poles.
c. Candida is a non motile yeast like fungus.
d. Mycoplasma has a gliding motility but has no special organ
of motility.

16. CHARACTER Naegleria Fowleri Acanthamoeba
Disease Primary Acute
meningoencephalitis
Granulomatous amoebic
encephalitis/ ulcerative
keratitis
Clinical course Acute infection Chronic
Infective form Trophozoite Trophozoite and cysts
Risk factor Swimming in
contaminated water
Immunodeficiency
Spread Direct neural Hematogenous
CSF leucocytes Neutrophils Lymphocytes
Diagnostic form in CSF Trophozoites Trophozoites and cysts

17. 1) Balamuthia :
causes Granulomatous amoebic encepalitis
2) Sappinia diploidea

18. -Only ciliate parasite of Humans
-Trophozoite is ciliated
-Both trophozoite and cysts are binucleated :
Macro and Micronucleus
- DOC : Tetracycline

20. Amebas in humans are found in the oral cavity and the intestinal tract.
Which one of the following statements best describes these intestinal
amebas?
A Infection with E. Histolytica is limited to the intestinal tract
B They are usually nonpathogenic
C They are usually transmitted as trophozoites
D They can cause peritonitis

21. Ans. B They are usually nonpathogenic
a. Many non-pathogenic amebae are present in the intestinal tract.
b. Infection with E. Histolytica is not limited to the intestinal tract and can
cause extra-intestinal disease like amoebic liver abscess.
c. When the organism invades the blood stream through the colon wall it
often lodges in the liver where it continues to multiply. The liver reacts and
creates an inflammatory wall around the organisms leading to abscess
formation.
d. Amebae are transmitted by cysts.

22. Q. A 33-year-old woman presents with acute, right upper quadrant
abdominal pain. She recalls that she had several months of bloody diarrhea.
CT scan of the liver demonstrates lesions that are interpreted to be
abscesses. Most likely cause? (AIPG 2009)
A Ascaris lumbricoides
B Entamoeba histolytica
C Enterobius vermicularis
D Salmonella typhi

23. Ans. B Entamoeba histolytica
a. This is the history of amebic liver abscess, which is caused by Entamoeba
histolytica.
b. The infective stage is tetranucleate cyst. Infection occurs by consumption of
contaminated food and water containing these cysts.
c. In intestinal amoebiasis flask shaped or water bottle ulcer is seen in the large
intestine.
The most common manifestation of extraintestinal amoebiasis is liver abscess.

24. Q. The single characteristic feature that is most diagnostic in
differentiating E. Histolytica from the other intestinal amoebae is
the (AIIMS May 2009)
A) Size of the cyst
B) Structure of the nucleus
C Presence of chromatoid bodies
D Number of nuclei

25. Ans. B Structure of the nucleus
a. Nuclear structure is the characteristic feature of E.
Histolytica by which one can differentiate E. Histolytica
from other amoebae.
b. Nucleus of E. Histolytica contains central karyosome and
finely granular chromatin material deposited on the nuclear
membrane.

26. Q. What is the composition of amebic chrom-atoidal bars?
(AIIMS Nov 2010)
A Ribonucleoprotein
B Glycogen
C Glycoprotein
D Lipoprotein

27. Ans. A Ribonucleoprotein
The chromatoid bars present in the cysts of Entamoeba endoplasm is
made of ribonucleoprotein.

28. Q.Encephalitis is caused by which parasite:
A Acanthamoeba
B Entamoeba histolytica
C Echinococcus
D Escherichia coli

29. Ans. A Acanthamoeba
a. Granulomatus amoebic encephalitis (GAE) is caused by a free living
amoeba, Acanthamoeba spp.
b. Disease occurs in debilitated/ immunosuppressed
c. Mode of infection is inhalation of a cyst or trophozoite in an infected
aerosol followed by dissemination to the blood from the lungs.
d. Prolonged chronic course unlike Primary amebic meningitis caused by
Naeglaria fowleri.
e. Diagnosis often requires a brain biopsy as CSF may be negative for
trophozoites or cysts.
f. Another species is Balamuthia mandrillaris.