hydatid cysts

Question 1

what are hydatid cysts?

Answer 1

An outer fibrous capsule is formed containing multiple small daughter cysts. These cysts are allergens which precipitate a type 1 hypersensitivity reaction.

Question 2

where are hydatid cysts common?

Answer 2

Hydatid cysts are endemic in Mediterranean and Middle Eastern countries

Question 3

what causes hydatid cysts?

Answer 3

tapeworm parasite Echinococcus granulosus.

Question 4

features of hydatid cysts?

Answer 4

Up to 90% of cysts occur in the liver and lungs
Can be asymptomatic, or symptomatic if cysts > 5cm in diameter
Morbidity caused by cyst bursting, infection and organ dysfunction (biliary, bronchial, renal and cerebrospinal fluid outflow obstruction)
In biliary rupture, there may be the classical triad of; biliary colic, jaundice, and urticaria

Question 5

ix for hydatid cyst?

Answer 5

ultrasound if often used first-line
CT is the best investigation to differentiate hydatid cysts from amoebic and pyogenic cysts

serology

Question 6

mx for hydatid cysts?

Answer 6

Surgery is the mainstay of treatment (the cyst walls must not be ruptured during removal and the contents sterilised first).

Question 7

what is this?

Answer 7

hydatid cyst of liver