Presentation
Right upper quadrant pain and fever.
Patient Data
A large irregular fluid-density lesion involving the dome (segment VIII) and segment V of the right hepatic lobe as well as segment IV of the left lobe showing rim enhancement (inner rim) and a thin outer ring of hypoattenuation ("double target sign"). There are multiple smaller peripheral lesions, mostly noted at segment VIII with similar characteristics. Some of these appear coalescent forming "cluster sign". The remainder liver parenchyma is unremarkable. Portal vein and hepatic veins are patent.
The common bile duct is patent along its entire course with pneumobilia extending to intrahepatic biliary ducts surrounding the lesion.
Case Discussion
This case represents the typical features of a liver abscess with cluster sign and double target sign. Gas within the biliary tree (pneumobilia) can be associated with liver abscesses.