Brain abscess caused by Streptococcus intermedius: Two case reports

BACKGROUND Although Streptococcus intermedius has been recognized as an important path ogen for abscess formation outside the central nervous system, the Streptoc occus milleri group, of which it is a member, has not been recognized as a specific pathogen for brain abscess, often thought to be caused by Streptoc occus viridans, which includes other streptococcal species. CASE DESCRIPTION Two cases of brain abscess in the left frontal lobe caused by S. intermediu s, which responded well to antimicrobial treatment combined with needle asp iration, are presented, In the first patient, the predisposing disease was paranasal sinusitis of the frontal and ethmoid sinuses. In the second patie nt, the source of the pathogen was not detected despite extensive examinati on. The patients underwent aspiration of pus under ultrasound guidance in t he first patient, and via a computed tomography-guided stereotactic procedu re in the second patient. They subsequently received appropriate antimicrob ial therapy against S. intermedius isolated from the pus culture. Both pati ents were discharged without any neurological deficits. CONCLUSION It is important to recognize S. intermedius as a pathogen of brain abscess, and to be aware of its predisposing factors, i.e., mucosal disturbance and liver abscess. (C) 1999 by Elsevier Science Inc.