Citrobacter koseri: an unusual cause of pyogenic liver abscess

Hepato-Duodenal Fistula Complicating a Pyogenic Liver Abscess: An Unusual Presentation

An elderly male with type 2 diabetes mellitus was admitted to the emergency ward with fever and pain over the right hypochondrium since one month. An abdominal ultrasound revealed an ill-defined hypoechoic lesion with multiple air foci measuring 8 x 6 x 4 cm within the left lobe of the liver implicating segments III b and IV. A contrast-enhanced computed tomography (CECT) scan of the abdomen showed a similar lesion with leakage of oral contrast into the dependent areas of the collection from a rent in the antero-inferior aspect of the first part of the duodenum. Hepato-duodenal fistula or entero-hepatic fistula secondary to pyogenic liver abscess is an atypical and unusual complication requiring a high degree of suspicion for its diagnosis. Though optimal therapy for its management is still not known, early diagnosis with prompt initiation of therapy is imperative to reduce mortality.

Fusobacterium nucleatum: a rare cause of pyogenic liver abscess

While pyogenic liver abscesses are uncommon, they are associated with significant mortality and morbidity. Most pyogenic liver abscesses are polymicrobial and are caused by enteric bacteria and anaerobes. Rarely, mono-microbial infections may occur, typically in immunocompromised individuals. We report the unusual case of a 69 year-old immunocompetent female who developed a pyogenic liver abscess due to Fusobacterium nucleatum infection, likely from a dental source. Poor oropharyngeal hygiene seems to have a major role in infection from this organism and therefore F. nucleatum should be considered as a differential for causes of pyogenic liver abscess in such patients. Drainage of the abscess and antibiotic therapy are the mainstays of therapy.