Echinococcus

Question 1

What is the class of Echinococcus?
and
The infectious species of Echinococcus?

Answer 1

Cestoidea, a tape worm

E. granulosus

Question 2

Clinical disease of Echinococcus

Answer 2

Hydatid disease

Question 3

Morphology

Answer 3

The 4 segmented tape worm,
Scolex, and 3 proglottids: immature, mature, and gravid

Scloex has 4 suction disks and 2 rows of hooklets

Question 4

What are the hosts of Echinococcus?

Answer 4

Humans are an accidental host, and it cannot reproduce in them.

Dogs are the main host,

Sheep are the intermediate host.

Question 5

Transmission and clinical disease

Answer 5

fecal oral of eggs.
Eggs penetrate the GI and cause Hydatid disease.

Hydatid disease:
very slow growing cysts, over several years
but the cysts can get huge, 20 cm.
Cysts have “Egg-Shell Calcification”and fill with fluid and hydatid sand of the worms failed reproduction, hydatid sand in biopsy is diagnostic, but biopsy is very dangerous and can cause anaphylaxis and acute abdomen (severe/debilitating abdominal pain, peritonitis other GI inflammation) if the cysts breaks or leaks.

Liver is the most frequent site
Lung next,
Brain next.

Question 6

Treatment of Echinococcus infection

Answer 6

Extremely careful surgical removal of cysts without rupturing them.
Ethanol may be injected inside first to kill them, but this is risky
Albendazole and/or Praziquantel if inoperable.