Fusobacterium necrophorum endocarditis with intracranial abscesses: A case report and review of the literature

Fusobacterium species are obligate anaerobic Gram-negative bacilli that are non-spore forming. The two most common species tied to human disease are F. nucleatum and F. necrophorum. They are commensal organisms in the oropharynx, gastrointestinal tract, and genital tract of humans, but can cause invasive infections especially in the head and neck such as periodontal disease and Lemierre's syndrome. F. necrophorum is an uncommon cause of infective endocarditis. We present a case of a previously healthy male who developed F. necrophorum endocarditis with multiple sites of pyogenic abscess formation.

Learning objective: Even among anaerobes, which account for less than 1 % of infective endocarditis (IE) cases, Fusobacterium necrophorum is rare. Specific laboratory conditions are necessary for growth, leading to delays in diagnosis. Severe disease is common given its virulence and predisposition for thrombophlebitis. While uncommon, it is crucial to maintain a degree of suspicion for Fusobacterium IE especially in individuals without prior cardiac disease whose infections were preceded by potential head and neck source.