Fusobacterium organisms are anaerobic, Gram-negative bacilli that bare a strong resemblance to
certain Bacteroides species.
Under the microscope, they are normally spindle-shaped cells with sharp ends.
Both bacteria are normal gut inhabitants but are capable of causing
serious infection. Fusobacterium species,
the most common of which is F. nucleatum, are associated with pleuropulminary infections and
disease. They are also capable of causing infection in the oral cavity (the mouth). F. nucleatum
has been cited as one of the causes of gingivitis. Identification of these bacteria