Cestodes- Taenia Flashcards Preview

Parasitology > Cestodes- Taenia > Flashcards

Flashcards in Cestodes- Taenia Deck (32):
1

What are the hosts of Taenia saginata (aka beef tapeworm)?

definitive host: humans only
intermediate: host: cattle only

2

What is the cysticercus?

tapeworm stage where the scolex is invaginated inside and where it will evaginate. soybean-like in shape. common to all Taenia species

3

What is particular about the Taenia saginata scolex?

have four suckers and lacks hooks

4

Which organs do the mature proglottids of Taenia saginata have?

both male and female organs

5

How can Taenia saginata gravid proglottids be identified?

have 15 or more branches on each side of the uterus

6

Why are the eggs of Taenia saginata not used for diagnosis?

all eggs of parasites from the Taeniidae family have identical eggs

7

Will Taenia saginata develop if a cow ingests an egg?

yes

8

Will Taenia saginata develop if a cow ingests a cysticercus?

no

9

Will Taenia saginata develop if a human ingests an egg?

no

10

Will Taenia saginata develop if a human ingests a cysticercus?

yes

11

What are the hosts of Taenia solium (aka pork tapeworm of humans)?

definitive host: humans only
intermediate host: pigs only

12

What makes Taenia solium more dangerous than Taenia saginata?

humans can be accidental intermediate hosts

13

What is particular about the Taenia solium scolex?

has 4 suckers and 2 circles of hooks

14

How can Taenia solium gravid proglottids be identified?

have 14 or more branches on each side of the uterus

15

What is the diagnostic stage for Taenia solium?

the gravid proglottids

16

What is cysticercosis?

When humans ingest eggs or become auto-infected. can cause neurocysticercosis (cysticercus infection in the brain) with symptoms of seizures, mental disturbances,
focal neurologic deficits, and signs of space‐occupying intracerebral lesions

17

How can cysticercosis be diagnosed?

need to demonstrate cytircercus in the involved tissue. Taenia solium infection indicates taeniasis, not cysticercosis

18

How can cysticercosis be treated?

a combination of anti-parasitics and anti-inflammatories used. surgery used in case of eye infections, not responsive to drugs, or to reduce brain edema

19

How can the adult Taenia solium worms be treated?

praziquantel. increases the worm's permeability to calcium ions

20

What are the hosts of Echinococcus granulosa?

definitve host: dogs and other Canidae
intermediate host: sheep + other herbivores, humans

21

Which variety of Echinococcus granulosa infects native Canadian's?

Echinococcus granulosa var. canadiensis aquired from moose and caribou

22

What is hydatid disease?

aka. echinococcosis. when the juvenile stage of the parasite develops into a large, fluid-filled cyst (hydratid cyst)

23

How can Echinococcus granulosa be distinguished from other tapeworms?

one of the smallest tapeworms. scolex has 4 suckers with hooks. has only scolex, neck, one immature proglottid, one mature proglottid, and one gravid proglottid at a time.
egg cannot be distinguished from Taenia species

24

Which stage of Echinococcus species cause echinococcosis?

the larval stage

25

Which species causes cystic echinococcosis?

Echinococcus granulosus

26

Which species causes alveolar echinococcosis?

Echinococcus multilocularis

27

Where does Echinococcus granulosus occur?

worldwide, mostly in rural grazing areas

28

Where does Echinococcus multilocularis occur?

northern hemisphere

29

What is the pathology of cystic echinococcosis?

symptoms only occur when cysts become very large. cysts rupturing causes fever, anaphylactic shock, cyst dissemination. mostly liver and lung involvement, but also brain, bones, heart

30

What is the pathology of alveolar echinococcosis?

affects the liver as a slow-growing tumor. causes abdominal pain, biliary obstruction, occasionally metastatic lesions in lungs and brain

31

How can echinococcosis be diagnosed?

ultrasonography or other imaging techniques supported with serologic tests

32

What is the treatment for echinococcosis?

surgery to remove cyst may not be 100% effective, so albendazole may be used to prevent recurrence.

Albendazole causes degenerative alterations in the tegument and intestinal cells of the worm by binding to tubulin, which inhibits its assembly into microtubules.