Hepatic abscess


Findings: fluid collection with thick rim enhancement, well defined, consistent with hepatic abscess

  • Objectives:

    • To review segmental anatomy of the liver

    • To review the classic appearance of hepatic abscesses of various etiologies

  • Protocoling:

    • Contrast enhanced CT scan

  • Key Points:

    • Anatomy:

      • Review segmental anatomy of the liver

    • Pyogenic abscess:

      • Etiology: biliary (ascending cholangitis), portal venous (diverticulitis, appendicitis, etc), septicemia, direct extension, traumatic.

      • Classic CT findings: hypodense mass/cluster of smaller cystic masses, enhancing capsule, gas < 20% of cases

      • Can be indistinguishable from necrotic metastasis

      • Management options: percutaneous aspiration, antibiotics

    • Hydatid cyst (echinococcal)

      • Classic CT findings: uni or multilocular, peripheral “daughter” cysts within, “water lily” sign with endocyst rupture - appears as floating membranes, can have peripheral calcifications

      • Management options: medical (anti-parasitic), aspiration, surgical

      • Aside: E. granulosus most common, E. multilocularis is rare more aggressive form

    • Amebic abscess:

      • Classic CT findings: sharply defined, round, solitary hypodense mass with thick rim/capsular enhancement.

      • Management: 90% respond to antimicrobial therapy (metronidazole). Drainage in special situations (including if unsure of diagnosis).

    • Candidiasis

      • Classic CT finding: multiple microabscesses

      • Differential:

        • Multiple hepatic cysts

        • Biliary hamartomas (von Meyenberg complexes)

        • Multiple small metastases/lymphoma

        • Caroli’s disease

      • Management: antifungal

    • Complications: Venous thrombosis, spread to subphrenic space, recurrence