To compared the difference of aerobic and facultative anaerobic blood culture bottles BacT/ALERT FA Plus, FA, PF Plus, PF and SA, as well as anaerobic and facultative anaerobic bottles BacT/ALERT FN Plus, FN and SN in the detection of simulated bacteremia samples, and to verify the accuracy of monitoring blood volume with BacT/ALERT VIRTUO blood culture instrument.

23 kinds of bacteria were selected to prepare bacterial suspension. Healthy human blood and bacterial suspension were added into the bottles, and cultured in two blood culture systems respectively. The mean detection time (time-to-detect, TTD) and positive growth were compared. A certain amount of phosphate buffer saline (PBS) was injected into the blood culture bottles, and then placed in the BacT/ALERTVIRTUO blood culture instrument to get the monitoring volume, and calculate the difference between the injected volume and the monitoring volume.

Except for Staphylococcus hominis and Cryptococcus neoformans, the positive detection rates of the other 21 strains were 100%. There was no significant difference in the average TTD time of the five kinds of aerobic bottles in the detection of aerobic and facultative anaerobic bacteria and fungi. For the detection of anaerobes and facultative anaerobes, SN bottle was the fastest. In the detection of aerobic and facultative anaerobes, anaerobic and facultative anaerobes, the average TTD time of BacT/ALERTVIRTUO blood culture instrument was shortened by 1.5~8 h and 3~8 h compared with BacT/ALERT 3D blood culture instrument, and the difference was statistically significant. The difference between the monitoring volume and the actual injection volume was no statistical difference.

There was no significant difference in the ability of five kinds of aerobic bottles to detect common bacteremia specimens. The anaerobic bottle SN is superior to FN and FN Plus bottles in shortening the detection time. BacT/ALERTVIRTUO blood culture instrument can significantly shorten the detection time of common bacteremia samples and is accurate and reliable in monitoring blood volume.