title: Fusobacterium liver abscess.
abstract: Fusobacterium is well characterized as an oropharyngeal pathogen that may induce a septic thrombophlebitis by direct extension of abscess into an adjacent neck vessel (Lemierre's syndrome); its potential for visceral abscess formation, however, remains under-recognized. A 65-year-old man with a recent history of multiple rim-enhancing liver lesions presented to the emergency room with fever and abdominal pain. Based on interval increase in the size of the lesions, abscess was suspected. A liver biopsy was performed, and although no organism could be identified on routine microscopy, Warthin-Starry stain revealed Gram-negative bacilli consistent with an anaerobic Fusobacterium species as the underlying etiology of liver abscess formation. Subsequent anaerobic culture results confirmed the diagnosis. This case highlights the importance of consideration for Fusobacterium infection in the setting of liver abscess if anaerobic organisms have not yet been excluded on initial culture evaluation.
authors.affiliation: Department of Pathology, University of California, San Francisco, San Francisco, Calif., USA.
authors.forename: Ben D
authors.initials: BD
authors.lastname: Buelow
authors.affiliation: Kaiser Permanente, Santa Clara, Calif., USA.
authors.forename: Joelle M
authors.initials: JM
authors.lastname: Lambert
authors.affiliation: Department of Pathology, University of California, San Francisco, San Francisco, Calif., USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Gill
keywords: Fusobacterium necrophorum Liver abscess; Negative culture; Warthin-Starry stain