096 Validation of a rapid extraction procedure, bruker compass IVD software and the bruker MBT-STAR carba kit to allow for rapid diagnosis of sepsis and direct detection of carbapenem-resistant enterobactericeae (CRE)

Background Septicaemia is a serious clinical condition with ˜1 23 000 cases of sepsis a year in England. One of the key methods of diagnosis is the Bruker Sepsityper kit and MALDI ToF. Although this method has improved diagnosis, the extraction technique is complicated and time-consuming. This investigation looks at a new rapid and shortened extraction procedure for identification of isolates from blood cultures bottles as well as direct detection of Carbapenmase Resistant Enterobactericeae (CRE). Material/methods 80 blood cultures were tested. 60 were spiked bottles with 6 known control organisms. 10 of the 60 spiked blood cultures were known CRE isolates which were then forwarded for direct CRE testing using the Bruker MALDI MBT STAR-Carba IVD Kit. 20 blood cultures were from patient specimens. All blood cultures were tested using the full extraction method and a shortened method. Isolates were identified on the Bruker MALDI ToF Biotyper and were analysed using the Bruker MBT Compass and the Bruker MBT Compass IVD. Results 6 species of bacteria were identified. The Compass correctly identified 70/80 samples for both the shortened and standard Sepsityper extraction. The Compass IVD correctly identified 76/80. 3 out of 10 CRE were detected by the MBT STAR – Carba Kit. The MALDI-ToF identification scores for the shortened Sepsityper extraction procedure were lower than the full extraction method. The majority of results from the full extraction method were >2.0, compared to averaging 1.9 for the shortened method. Scores of >2.0 with the shortened extraction method were mainly linked to Gram-negative species. Conclusion The results demonstrate that the shortened Sepsityper extraction method was able to correctly identify all isolates, apart from 10/4 respectively. This investigation also showed that it is now possible to identify CRE directly from Blood Cultures using the MBT STAR-Carba IVD.