Bacteroides infection in man is a relatively neglected subject both clinically and experimentally. The taxonomy of the Bacteroidaciae is confusing, and the pathogenecity of these organisms remains obscure.
The genus Bacteroides includes Gram-negative, non-spore forming, rod-shaped bacteria with rounded ends which are obligate anaerobes and which do not take the acid-fast stain. These organisms normally inhabit the mouth, vagina, and intestines of animals. In the feces of man, they may outnumber Escherichia coli (1).
The Bacteroides were reported to be the etiologic agents in various suppurative lesions for the first time in 1897 when Veillon and Zuber (2) and Halle