Comparison of 'time to detection' values between BacT/ALERT VIRTUO and BacT/ALERT 3D instruments for clinical blood culture samples

- A reduction in the time to detection of microorganisms with the BacT/ALERT VIRTUO system compared to the BacT/ALERT 3D system has been suggested.
- Microorganisms isolated from blood culture were grouped into eight different categories.
- In positive bottles, five of the eight groups of microorganisms were detected earlier in the BacT/ALERT VIRTUO system.
- The earlier detection of microorganisms will lead to the more rapid use of targeted antibiotic therapy.

ObjectivesThe early detection of bacteraemia and fungemia is of paramount importance to guide antimicrobial therapy in septic patients. In this study the 'time to detection' (TTD) value for the new blood culture system BacT/ALERT VIRTUO (VIRTUO) was evaluated in 1462 positive clinical bottles and compared with the TTD for 1601 positive clinical bottles incubated in the BacT/ALERT 3D system (BTA-3D).MethodsThe most representative microorganisms isolated from bottles incubated in both blood culture systems were divided into eight categories (in order of frequency): coagulase-negative staphylococci (CoNS), Escherichia coli, Enterobacteriaceae (other than E. coli), Staphylococcus aureus, Enterococcus spp, viridans group streptococci, Pseudomonas aeruginosa, and Candida spp.ResultsThe comparison of TTD values for the two blood culture systems strongly indicated that growth of the first five groups listed above was detected earlier with VIRTUO than with BTA-3D (p < 0.05).ConclusionsThe new VIRTUO blood culture system can reduce the TTD for more than 75% of isolated microorganisms.