The St George Hospital Microbiology department perform bioburden testing of blood products collected from HPCs, received from the Cell and Molecular Therapies (CMT) laboratory at RPAH. The Microbiology lab is introducing the new BacT/Alert® Virtuo™ to replace the BacT/Alert® 3D™ system. The Virtuo™ instrument is an automated microbial test system capable of incubating, agitating and continuous monitoring for reduced time-to-detection of aerobic, facultative, and anaerobic microorganism growth from blood and other body fluids.
Bact/ALERT® FAN Plus aerobic, anaerobic and paediatric bottles manufactured by BioMerieux are used with both blood culture instruments and the adsorbent polymeric beads and media volume remained unchanged.
AIM:
The testing will compare BacT/Alert® 3D™ and BacT/Alert® Virtuo™ monitoring systems and establish that the Virtuo™ is fit for purpose to detect contamination of blood products.
METHOD:
A group of 13 fungi, aerobic and anaerobic bacteria were used during validation. The organisms were inoculated into FAN Plus aerobic, anaerobic and paediatric bottles in a seeded bottle trial. The bottles contained human plasma and processed cells collected and processed from patients at at RPAH.
RESULTS
In the seeded trial and in the bottles containing patient plasma, all 13 organisms were isolated within the incubation period from at least one of the FAN Plus aerobic, anaerobic or paediatric bottles loaded after inoculation. All expected organisms were isolated from the FAN Plus paediatric bottles containing processed cells with DMSO.
CONCULSIONS
This validation confirms that the new method using the new BacT/Alert® Virtuo™ instrument and FAN Plus bottles range is able to detect a range of organisms from patients undergoing treatment regimes that include chemotherapy and/or mobilisation regimes (e.g. granulocyte colony stimulating factor), and from processed cells for cryopreservation with the addition of DMSO. It also demonstrates that the 5-day incubation period is sufficient to recover fungi, aerobic and anaerobic bacteria.