Internal Medicine

P1: SBT

0521779407-03 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 19:6

110 Amebic Liver Abscess

& IFAT for 6 mo; CAP can be negative as early as 1 wk after start of

treatment

■Aspiration of abscess: yellow/brown (anchovy), odorless fluid; aspi-

rate only if diagnosis uncertain or rupture imminent

Imaging

■US/CT: round/oval, mostly single (sometimes multiple); hypoe-

choeic/low density compared to normal liver

■CXR: right hemidiaphragm w/ blunted costophrenic angle, atelec-

tasis

differential diagnosis

■Pyogenic abscess, hydatid cyst

management

What to Do First

■Obtain history (incl geographic), physical exam, imaging

■Imaging confirms diagnosis of cyst or abscess

General Measures

■Suspected amebic abscess: start therapy while awaiting serologic

confirmation

■Aspirate if diagnosis unclear, rupture imminent, or pt critically ill

specific therapy

Treatment options

■Metronidazole for 5–10 d (alternative options tinidazole or chloro-

quine), followed by luminal amebicides: diloxanide furoate for 10 d

or diiodohydroxyquin for 20 d

■Surgical drainage: ruptured abscess

follow-up

■Clinical: resolution of fever & pain

■Imaging: abscess shrinkage

complications and prognosis

Complications

■Rupture of abscess into chest, pericardium, or peritoneum

■Secondary infection (usually after aspiration)

■High risk for complications: age >40, corticosteroid use, multiple

abscesses, abscess w/ diameter >10 cm