U2 - Amoebae

Question 1

Phylum Sarcodina species

Answer 1

Pathogenic: Entamoeba histolytica
Commensals:
1. E. dispar
2. E. moshkovskii
3. E. hartmanni
4. E. coli
5. Endolimax nana
6. Iodamoeba butschlii

Question 2

Identify the amoeba:
Most invasive of the Entamoeba parasites

Answer 2

Entamoeba histolytica

Question 3

Identify the amoeba:
Only member to cause colitis and liver abscess

Answer 3

Entamoeba histolytica

Question 4

Entamoeba histolytica:
Mechanisms for virulence

Answer 4

1. production of enzymes or other cytotoxic substances
2. contact-dependent cell killing
3. cytophagocytosis

Question 5

Entamoeba histolytica:
Cases may manifest as?

Answer 5

1. Asymptomatic
2. Amebic Colitis
3. Ameboma
4. Amebic Liver Abscess

Question 6

Identify the condition:
abdominal pain + diarrhea +/-
blood & mucus in the stools

Answer 6

Amebic Colitis

Question 7

Identify the condition:
Children may develop fulminant colitis (severe bloody diarrhea + fever + ab pain)

Answer 7

Amebic Colitis

Question 8

Identify the condition:
A mass-like lesion with abdominal pain and a history of dysentery

Answer 8

Ameboma

Question 9

Identify the condition:
Can be mistaken as a carcinoma

Answer 9

Ameboma

Question 10

T/F:
Ameboma is always symptomatic.

Answer 10

False;
May be asymptomatic

Question 11

Identify the condition:
most common extra-intestinal form of amebiasis

Answer 11

Amebic Liver Abscess

Question 12

Identify the condition:
Usually presents with fever and right upper quadrant pain

Answer 12

Amebic Liver Abscess

Question 13

Entamoeba histolytica:
diagnosis

Answer 13

1. DFS
2. Concentration techniques (FECT)
3. PCR
4. Serological tests (ELISA): for ALA
5. Ultrasound, CT scan, MRI

Question 14

Entamoeba histolytica:
treatment

Answer 14

1. Metronidazole
2. Diloxanide furoate

Question 15

Entamoeba histolytica:
epidemiology

Answer 15

1. Amebiasis: 1-5% worldwide
2. 3rd most important parasite
   (malaria, schistosomiasis)

Question 16

Entamoeba histolytica:
prevention and control

Answer 16

1. Proper sanitation
2. Safe water supply
3. Good personal hygiene
4. Proper food preparation
5. Vaccines

Question 17

Identify the amoeba:
Non-pathogenic and morphologically similar to E. histolytica

Answer 17

E. dispar
E. moshkovskii

Question 18

Identify the amoeba:
Ameba of swine (pigs)

Answer 18

Iodamoeba butschlii

Question 19

Iodamoeba butschlii:
prominent features

Answer 19

1. Uninucleated with a large eccentric karyosome; with achromatic granules “Basket of Flowers”
2. Large Glycogen Vacuole

Question 20

Identify the Free Living Pathogenic Amebae:
Found Inhabiting Lakes, Pools, Tap Water, Air Conditioning Units and Heating Units

Answer 20

1. Acanthamoeba
2. Balamuthia
3. Naegleria

Question 21

Naegleria fowleri:
Important Stages

Answer 21

1. Cyst
2. Trophozoite

Question 22

Naegleria fowleri:
Entry into the body

Answer 22

1. Olfactory Epithelium
2. Respiratory Tract
3. Skin
4. Sinuses

Question 23

Naegleria fowleri:
Disease Manifestation and Pathology

Answer 23

Primary Amebic Meningoencephalitis

Question 24

Naegleria fowleri:
Diagnosis

Answer 24

1. Wet Mount Examination of CSF
2. Smears stained with Wright’s or Giemsa
3. Biopsy
4. CSF Analysis
5. Culture
6. Molecular Methods

Question 25

Naegleria fowleri:
Treatment and Prevention

Answer 25

Amphotericin B with Clotrimazole

Question 26

Acanthamoeba spp.:
Morphologic Forms

Answer 26

1. Cyst
2. Trophozoite

Question 27

Acanthamoeba:
Disease Manifestation and Pathogenesis

Answer 27

1. Granulomatous Amebic Encephalitis
2. Amebic Keratitis

Question 28

Acanthamoeba:
Diagnosis

Answer 28

1. Usually diagnosed after death (GAE)
2. Biopsy
3. Corneal Scrapings
4. Culture
5. Molecular Methods

Question 29

Acanthamoeba:
treatment

Answer 29

1. Very fatal once cerebral manifestations appear
2. Fluorocystine, ketoconazole, amphotericin B