Fusobacterium nucleatum : A cause of subacute liver abscesses with extensive fibrosis crossing the diaphragm, mimicking actinomycosis.

Introduction Fusobacterium nucleatum is a Gram-negative, obligate anaerobic bacterium which predominantly resides within the oral cavity and causes acute abscesses and venous thrombosis, primarily in the head and neck region, but could have unique clinical presentations in different anatomical regions of body. Case report We present a case of subacute liver abscesses extending to the lung. The histopathological examination showed extensive necrosis and fibrosis. The chronic course, extensive fibrosis and extension across the anatomic barriers were suggestive of actinomycosis. two sets of blood cultures grew Fusobacterium nucleatum , only 16s rRNA analysis of the liver tissue and pleural fluid revealed F. nucleatum DNA without other organisms. The clinical and pathological features of our case illustrate that F. nucleatum may mimic actinomycosis. Conclusions This case illustrates that F. nucleatum should be considered in patients with subacute infections with extensive fibrosis that crosses anatomic barriers, mimicking actinomycosis. [ABSTRACT FROM AUTHOR]