Presentation
Right upper quadrant pain for 1 week.
Patient Data
CT demonstrates a large irregular fluid-density lesion in segment VI of the liver with "double target sign" and "cluster sign" which consistent with pyogenic abscess.
CT findings show the typical features of the pyogenic abscess.
Double target sign: The inner ring (abscess membrane-blue arrow) enhances early. The outer rim (edema parenchyma - yellow arrow) only enhances on delayed phase.
Cluster sign: The multiple smaller abscess coalesce to form a large abscess cavity.
Percutaneous US-guided drainage was performed. The culture of Klebsiella pneumoniae was grown.
Case Discussion
This case demonstrates the pyogenic hepatic abscess with the bacterial agent is K.pneumoniae.
K.pneumoniae liver abscesses tend to be less liquefied than other pyogenic agents, so the lesion may appear solid and mimic a hepatic tumor at US 1. A new hypervirulent Asian variant of K.pneumoniae may affect the other organs with the increased morbidity and mortality from hvKP infection 2.