Detection of anaerobic bacteria in blood cultures by lysis filtration.

An anaerobic adaptation of the lysis-filtration system for detection of anaerobic microorganisms in blood is described. The method was compared with a conventional broth bottle system in detection of anaerobic bacteremia after oral surgery. Of 43 blood samples obtained during and after surgery, 31 were positive with the lysis-filtration system and 17 were positive with the broth bottle system. Sixteen aerobic and 62 anaerobic strains were isolated with the lysis-filtration system versus 9 aerobic and 22 anaerobic strains with the broth bottles. The lysis-filtration technique was thus superior to the conventional broth bottle method in detecting anerobic bacteria.