Primary Klebsiella Pneumoniae Liver Abscess from the Viewpoint of Radiologist: 3 Case Reports and Literature Review

Abstract

Background: Klebsiella pneumoniae (K. pneumoniae) liver abscess is increasingly prevalent as the leading cause of pyogenic liver abscesses in certain Asian countries, can present with metastatic infections associated with poor prognosis and outcomes when diagnosis is delayed. We report three cases of primary K. pneumoniae liver abscess and highlight specific imaging features in these cases.
Case presentation: Three cases involved a 44-year-old man, a 50-year-old man, and a 71-year-old woman who were hospitalized due to severe fever lasting 4-5 days prior to admission. All patients’ laboratory tests showed elevations in serum alanine and aspartate aminotransferases, bilirubin as well as leucocyte count, and C-reactive protein. Imaging revealed a large single abscess without “double-target sign” and some similar features: a thin-walled multiloculated “pseudosolid” with “turquoise sign”, suggesting a pyogenic liver abscess caused by K. pneumoniae. No underlying hepatobiliary disease was found. Blood and abscess pus cultures confirmed K. pneumoniae as the causative organism. No distant infection lesions were found.
Conclusion: Recognizing key imaging features of K. pneumoniae liver abscess, such as a unifocal, thin-walled multiloculated "pseudosolid" abscess with the "turquoise sign" and no underlying hepatobiliary disease, aids radiologists in early diagnosis and treatment, leading to better outcomes and fewer metastatic infections.