Is "primary" subphrenic abscess caused by Streptococcus milleri a result of unrecognized gastrointestinal perforation?

An unusual case of subphrenic abscess presenting as empyema of the pleural cavity is described. The abscess developed secondarily to an occult perforation of the gastrointestinal tract, which was, diagnosed indirectly by the discovery of a fishbone within the abscess. Isolation of Streptococcus milleri from the pus was an important clue for the existence of an underlying gastrointestinal pathology.