CONTROLLED CLINICAL LABORATORY COMPARISON OF BACTEC PLUS AEROBIC F RESIN MEDIUM WITH BACT/ALERT AEROBIC FAN MEDIUM FOR DETECTION OF BACTEREMIA AND FUNGEMIA/

Blood specimens collected from adult patients with suspected sepsis in four medical centers were inoculated into BACTEC Plus/F and BacT/Aler t FAN aerobic culture bottles, Both bottles of 7,401 bottle pairs cont ained the prescribed blood volume of 8 to 12 ml. Bottles were incubate d in their respective instruments for a standard 7-day protocol or unt il the instruments signaled that they were positive, A total of 720 is olates that were judged to represent true infections were recovered fr om 338 patients; 451 isolates were recovered from both bottles, 143 we re recovered from only the Plus/F bottle, and 126 were recovered from only the FAN bottle (P was not significant), Although more Histoplasma capsulatum isolates were recovered from Plus/F bottles (P < 0.005), t here were no other statistically significant differences in recovery r ates of individual species or groups of organisms between the two syst ems, Of 329 monomicrobic patient septic episodes, 244 episodes were de tected by both blood culture systems, 40 were detected only by the BAC TEC system, and 45 were detected only by the BacT/Alert system (P was not significant), There was no significant difference between the two systems in the detection of septic episodes among patients receiving a ntibiotic therapy at the time of blood cultures, Of the cultures found to be positive within the first 72 h of incubation, detection was on average earlier by the BACTEC system (16.9 h) than by the BacT/Alert s ystem (18.7 h), Larger differences in average time to detection were s een with streptococci (10.7 h by the BACTEC system and 17.9 h by the B acT/Alert system) and yeasts (an average of 29.4 h by the BacT/Alert s ystem versus 37.2 h by the BACTEC system), With the exception of the d ifferences noted above, BACTEC Plus/F aerobic resin and BacT/Alert aer obic FAN blood culture bottles were comparable in their abilities to r ecover aerobic and facultative organisms.