• The commonest plain X-ray chest finding is an elevated right dome of the diaphragm, i.e. more than 2.5 cm or more than one intercostal space higher than the left dome). Occasionally a localized bulge or tenting of the right dome of the diaphragm may be seen in a superiorly located abscess. 

• Fluoroscopy confirms these findings and in addition demonstrates restricted mobility of the diaphragm, though these findings are non-specific and may be seen in many other conditions e.g. subphrenic collections, subpulmonic effusions, further-more, other than the superior surface abscess, plain X-ray and fluoroscopy are not able to localize the abscess.

• On ultrasound an amoebic abscess appears as a round, subcapsular, hypoechoic area containing fine echoes which may layer in the dependant portions. In the early stages an amoebic abscess appears as a subtle area of decreased echogenicity. The ultrasound diagnosis is not pathognomonic as complicated cysts, haematoma, metastases and amoebic abscess may resemble with each other.

• CT scan appearances are in the form of a well-defined homogeneous, hypodense area, whose Hounsfield units are greater than a benign cyst and less than a tumour; though this is not always true, as there may be an overlap. Intravenous contrast defines and highlights the abscess very well. The wall of the abscess is relatively avascular, therefore it does not enhance however the periphery may appear a bit hyperdense due to compressed hyperemic liver parenchyma.

Aspiration may be required for:

1. Making a diagnosis  - typical anchovy sauce is aspirated. The pus is usually sterile and a biopsy of the wall is required to identify the organism.

2. When there is rapid clinical deterioration or inadequate response to therapy .