Anaerobic meningitis and bacteremia caused by Fusobacterium species.

In the two cases of anaerobic meningitis and bacteremia caused by Fusobacterium species described, upper respiratory tract infection preceded the onset of meningitis. Isolation of the causative organism and appropriate antibiotic therapy resulted in cures in both patients. Although extremely rare, these organisms should be considered as possible causative agents in meningitis when routine cultures are negative, and appropriate anaerobic culture techniques should be employed, especially when sinus, otitic, or mastoid symptoms precede or accompany the onset of meningitis. Susceptibility testing of these organisms is necessary to ensure proper therapy because of the resistance of some anaerobes to antibiotics commonly employed in meningitis. In this regard, metronidazole, which provides excellent cerebrospinal fluid levels, may prove to be an effective agent in anaerobic infections of the central nervous system.