Recovery of anaerobic microorganisms from clinical specimens in prereduced media versus recovery by routine clinical laboratory methods.

Prereduced anaerobically sterilized culture media, used with rigid adherence to the cultivation techniques described by Moore and his associates, were capable of recovering more than twice the number of anaerobic bacteria from clinical specimens than could be recovered by the conventional use of fluid thioglycolate medium and of blood-agar plates incubated anaerobically with hydrogen generation packets. No loss of clinical isolates was encountered with the more sensitive methods; however many of the isolates recovered only in prereduced media would not grow when placed into thioglycolate medium. A representative anaerobic isolate placed into aerobic transport broth was unable to survive beyond 30 min. Methods employing prereduced media were not difficult to master and were feasible for clinical laboratory use. Evidence implicating the gingival crevice flora as an important possible source of anaerobic bacteria that become involved in systemic infections was considered.