[Suburban amebiasis: the diagnostic aspects via computed tomography and echography and the percutaneous treatment of amebic liver abscesses].
BACKGROUND
Liver is the most common site of extraintestinal amebiasis and hepatic abscesses are the most frequent symptom, occurring in 3-9% of patients with amebic infection. Several studies have shown that drug treatment is more efficacious when combined with percutaneous drainage of the abscess, yielding quicker recovery and a positive body response. We report our US and CT findings in 16 patients with amebic abscesses, 12 of whom lived in a temperate peripheral area north-east of Naples. All patients had a clinical-diagnostic condition that we called "suburban amebiasis". Finally we report our personal experience with the US-guided therapeutic drainage of amebic abscesses with repeated cavity washings, which is important for positive parasitology.


METHODS
We retrospectively reviewed the findings of 16 patients (11 men and 5 women; age range 36-78 years; mean 52) with amebic abscesses of liver examined with US and CT. US with a 3.5 MHz transducer was the technique of choice in all patients. 94% of liver abscesses and some extraintestinal complications were easily shown with this technique. CT angiography was then performed to detail and clarify US findings. Abscesses over 4 cm in diameter were submitted to US-guided percutaneous treatment which permitted abscess drainage, the collection of material for parasitology and repeated cavity washings.


RESULTS
US showed multiple liver abscesses in 12 patients, which were multiseptate and formed by multiple hypo-/hyperechoic microabscesses in 4 of them. Four non-European patients had a single abscess, which is typical of tropical endemic forms. CT showed the amebic abscesses as hypodense roundish masses with clear-cut outline most often localized in the right lobe in the 12 multiple cases. After percutaneous drainage 13/16 patients (81%) reported less pain in the right hypochondrium and had a lower temperature; their hospitalization was also shorter.


CONCLUSIONS
Combined US and CT assessment facilitated the diagnosis of amebiasis and its differentiation from pyogenic abscess and hepatoma. The combination of US-guided drainage and drug treatment provides better results than either treatment alone and quicker improvement of patient conditions, with fewer extraintestinal complications. Percutaneous drainage should be used in abscesses bigger than 4-5 cm, those with questionable clinical-laboratory findings and finally those failing to respond to drug treatment alone. Positive parasitology of abscess content is related to repeated cavity washings after percutaneous drainage, likely because peripheral layers are much richer in amebae.
Salzano
A
A
Servizio di Radiologia, Ospedale Loreto Mare, Università degli Studi Federico II, Napoli.
Rossi
E
E
Carbone
M
M
Mondillo
F
F
De Rosa
A
A
Tuccillo
M
M
Capuano
N
N
Nunziata
A
A
D000328:Adult; D000368:Aged; D003287:Contrast Media; D004322:Drainage / Q000379:methods; D005260:Female; D006801:Humans; D007558:Italy; D008099:Liver / Q000000981:diagnostic imaging; D008101:Liver Abscess, Amebic / Q000175:diagnosis* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013383:Suburban Population; D007507:Therapeutic Irrigation / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D018084:Ultrasonography, Interventional / Q000379:methods
D003287:Contrast Media
Amebiasi sub-urbana: aspetti diagnostici con Tomografia Computerizzata ed ecografia e trattamento percutaneo degli ascessi amebici del fegato.