Parasitology II

Question 1

parasite in Giardiasis

Answer 1

Giardia Lamblia

Question 2

host and intermediate host of giardasis

Answer 2

host: beavers, dog, humans

intermediate host: none

Question 3

transmission of giardia

Answer 3

food borne or water borne transmission (environmental) –> transmitted in its cyst stage which is when it is infective

if diarrhea, it is commonly seen in its trophozoite stage which is not infective

Question 4

lifecycle of giardia

Answer 4

parasite is discontinuously released in feces (shed in showers)

Question 5

diagnosis of giardia

Answer 5

• cyst in dry stool (hard to find due to discontinuous release)
• trophozoite in watery stool
• therapeutic trial: eat capsule filled with corn attached to a string and trophs attach to capsule if present
• elisa antigen test
• immunofluorescent test (high specificity and high sensitivity but expensive)

Question 6

symptoms of giardia

Answer 6

traveller's diarrhea
Pale loose stools (foul smelling; fatty) Frequency 3-8 X daily
Abdominal distension
Flatulence – offensive
Abdominal pain
Weight loss - anorexia
Sulphorous belching

Question 7

pathogenesis of giardia

Answer 7

severity dependent on:
􏰁Number of organisms
􏰁Virulence of strain (Dog - low path) 
􏰁Host immunity
􏰁Mucosal damage
􏰁Secondary bacterial colonization

Question 8

groups at high risk of protracted giardia

Answer 8

immunosuppressed (AIDS patient)
sewage workers
crowded institutions/day care/ city centers
travelers

Question 9

treatment of giardia

Answer 9

metronidazole (flagyl)

tinidazole (tinidamax)

Question 10

control of giardia

Answer 10

improve water tx plants against giardia

Question 11

parasite in amoebiasis

Answer 11

entamoeba histolytica

Question 12

two types of amoebiasis

Answer 12

-Intestinal amoebiasis –> may result in
Amoebic Dysentery

􏰁-Invasive amoebiasis –> usually results in Amoebic Liver Abscesses (ALA)

Question 13

morphology of entamoeba histolytica

Answer 13

cyst containing four nuclei

Question 14

transmission of amoebiasis

Answer 14

ingestion of cysts - fecal oral route

Question 15

clinical manifestation of intestinal amoebic dysentery

Answer 15

􏰁-95% asymptomatic
-􏰁Symptomatic individuals (5%): Diarrhea –
inconsistent with gradual onset, No fever. Flatulence, Abdominal pain
-􏰁Frequency

Question 16

clinical manifestation of invasive ALA (amoebic liver abscesses)

Answer 16

• may form amoebic abscesses in: liver (majority), brain, skin, lungs, orbit, spleen and genitals
• 􏰁Fever
• 􏰁Tender Liver – Epigastric Pain 􏰁
• Hepatomegaly