Amoebic liver abscess in travellers: indication for image-guided puncture?

Although amoebic liver abscess due to Entamoeba histolytica is one of the most common parasitic infections worldwide, invasive disease remains uncommon in industrialized countries. Metronidazole is the standard of care for complicated and uncomplicated invasive amoebiasis. Puncture of amebic liver abscesses is a treatment option primarily for complicated abscesses (localized in left lobe, multiple, and/or pyogenic abscesses). The role of image-guided percutaneous puncture in initially uncomplicated liver abscess formations still remains unanswered. A subset of patients with uncomplicated amoebic liver abscesses, however, fails to respond to conservative treatment alone. We report two cases of amoebic liver abscess formations in Austrian travelers. Two males, aged 67 and 43, presented with fever, chills and fatigue. Four months prior to admission both patients travelled together to Goa, India, for 4 weeks. Computed tomography showed uncomplicated liver abscess formations and serology for E. histolytica was positive in both patients. Therapy with metronidazole 500 mg four times daily was initiated. Computed tomography then showed an increase in size of liver abscess formations in both patients after 13 and 10 days of intravenous metronidazole therapy, respectively. Patient 1 developed pleural effusion and patient 2 additional liver abscess formations. Therefore CT-guided percutaneous therapeutic catheter drainage of liver abscess formations was performed in both patients without complications. Real time PCR of abscess drainage was positive for E. histolytica in both patients. After completion of metronidazole, paromomycin 500 mg three times daily was initiated for seven days for elimination of cysts and both patients were discharged without further complaints. This report highlights that conservative monotherapeutic treatment alone may not be sufficient in some patients with initially uncomplicated E. histolytica liver abscess. Implementation of additional image guided percutaneous puncture may reduce mortality and disease related costs.