Abstract
Background
Bloodstream infections are a major cause of morbidity and mortality. BACT/ALERT VIRTUO (VIRTUO) blood culture system is an automated, closed system used with resin-containing media which may enhance the growth of microorganisms. Our objective was to assess the real-world performance of the VIRTUO system.
Methods
We retrospectively reviewed all blood cultures performed between January-December 2018 (VersaTREK) and January-December 2019 (VIRTUO) at a 1250-bed academic medical center. Blood culture positivity rates, contamination rates, and time from collection to arrival in the laboratory were compared pre- versus post-VIRTUO implementation. Contamination was defined as a single blood culture with common skin microbiota.
Results
A total of 101803 blood cultures were performed during the study period: 48969 (48.1%) were processed with VersaTREK system and 52834 (51.9%) with VIRTUO system. A decreased median time from collection until arrival to the laboratory was seen post-implementation (2.0 pre- vs. 0.8 hours post-implementation, p< 0.001). The positivity rate increased from 3987 (8.1%) pre-implementation to 6141 (11.6%) post-implementation (p < 0.001) (Table and Figure). Staphylococcus aureus was the most frequently isolated species for both periods and had higher recovery rate with the VIRTUO system (717 (1.5%) pre- vs. 1764 (3.3%) post-implementation, p< 0.001). Higher recovery rate was also noted for other Staphylococcus spp. in the post-implementation period (985 (2.0%) pre- vs. 1644 (3.1%) post-implementation, p< 0.001). No difference in the organism recovery rate was noted for Streptococcus spp., Enterococcus faecium, E. faecalis, Pseudomonas aeruginosa, Enterobacterales, and Candida spp. The inpatient contamination rate was higher post-implementation (1.5% pre- vs. 1.9% post-implementation, p < 0.001).
Comparison of blood culture positivity rate pre- vs. post-implementation, by culture location
Daily positivity rate for blood cultures processed at BJH during the study period
Conclusion
The VIRTUO system showed a higher rate of positive blood cultures compared to the VersaTREK system primarily from a higher detection of Staphylococcus spp. Further studies are needed to assess whether an increased rate of positive blood cultures is associated with changes in management and clinical outcomes.
Disclosures
All Authors: No reported disclosures
Comparative evaluation of the role of single and multiple blood specimens in the outcome of blood cultures using BacT/ALERT 3D (automated) blood culture system in a tertiary care hospital
