Multicenter evaluation of the Sepsityper (TM) extraction kit and MALDI-TOF MS for direct identification of positive blood culture isolates using the BD BACTEC (TM) FX and VersaTREK((R)) diagnostic blood culture systems

作者：Schieffer K M^*; Tan K E; Stamper P D; Somogyi A; Andrea S B; Wakefield T; Romagnoli M; Chapin K C; Wolk D M; Carroll K C

来源：Journal of Applied Microbiology, 2014, 116(4): 934-941.

DOI：10.1111/jam.12434

• MALDI-TOF MS
• Sepsityper
• sepsis
• bacteraemia
• blood cultures

Aims
(i) Evaluation of delayed time to blood culture extraction by the Sepsityper kit and impact of shipping pellets off-site for MALDI-TOF MS analysis. (ii) Comparison of Sepsityper and laboratory-developed extraction methods from a literature review.
Methods and Results
Using two blood culture systems (BD BACTEC and VersaTREK), we extracted 411 positive blood cultures using the Sepsityper kit to mimic a potential protocol for institutions without a MALDI-TOF MS. Extracted pellets were shipped and analysed on the Bruker UltraflexIII. Successful extraction of 358 (87 center dot 1%) samples was determined by the presence of detectable proteins. MALDI-TOF MS correctly identified 332 (80 center dot 8%) samples.
Conclusions
Delayed time to extraction did not affect Sepsityper extraction or MALDI-TOF MS accuracy. The extracted pellets remain stable and provide accurate results by MALDI-TOF MS when shipped at room temperature to off-site reference laboratories.
Significance and Impact of the Study
This is the first study to show that institutions without a MALDI-TOF MS can take advantage of this innovative technology by shipping a volume of blood to an off-site laboratory for extraction and MALDI-TOF MS analysis. We also performed a literature review to compare various extraction methods.

• 出版日期2014-4