Learning objectives
To review the spectrum of hydatidosis’ clinical presentation,
focusing on abdominal involvement.
To illustrate its most typical imaging features in hepatic,
renal,
splenic and peritoneal disease.
Background
Epidemiology
Hydatidosis is a worldwide zoonosis caused by the larval stage of Echinococcus tapeworm,
there being four species known to be pathogenic in humans.
The two main types of Echinococcus infections are E.
granulosis,
which is the most common one,
and E.
multilocularis,
that is more invasive,
mimicking a malignancy.
Hydatid Disease (HD) is still endemic in Middle East,
Australia,
New Zealand,
Africa,
South America and Mediterranean Europe,
including Portugal.
[1-4]
Life cycle of Echinococcus granulosis
Dogs are usually the definitive hosts,
whereas ruminants like...
Imaging findings OR Procedure details
Ultrasonography (US) is usually the screening method of choice,
particularly useful for detection of cystic membranes,
septa and hydatid sand [6,
17].
Although it may display the majority of the findings of Computed Tomography (CT),
this,
with its high sensitivity (94%),
might be indicated in cases in which US fails due to patient-related difficulties and in the presence of disease complications,
as well as to determine the resectability of the lesions when surgery is indicated [6,
12,
18,
19].
Intravenous administration of contrast material is...
Conclusion
As hydatidosis is mostly asymptomatic with negative serologic tests,
its diagnostic approach is essentially based on imaging findings,
the familiarity with the most characteristic patterns being advantageous to any Radiologist,
especially in endemic areas.
References
King CH.
Cestodes (tapeworms).
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Bennett JE,
Dolin R.
Principles and Practice of Infeccious Diseases.
4th ed.
New York,
Churchill Livingstone,
1995,
2544-2553.
Lewall DB.
Hydatid Disease: biology,
pathology,
imaging and classification.
Clin Radiol 1998,
52:863-874.
Beggs I.
The Radiology of Hydatid Disease.
AJR Am J Roentgenol 1985,
145:639-648.
Webb WR,
Brant WE,
Major NM.
Fundamentals of Body CT.
3rd ed,
Sounders Elsevier,
2012,
p229-230,
267-268.
Harris KM,
Morris DL,
Tudor R et al.
Clinical and Radiographic features of Simples and Hydatid Cysts of...