Rapid Sepsityper in clinical routine: 2 years’ successful experience

Abstract

Introduction. Rapid identification of the causative agent of sepsis is crucial for patient outcomes. Aim. The Sepsityper sample preparation method enables direct microbial identification of positive blood culture samples via matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF MS). Hypothesis/Gap statement. The implementation of the Sepsityper method in the routine practice could represent a fundamental tool to achieve a prompt identification of the causative agent of bloodstream infections, and therefore accelerate the adoption of the proper antibiotic treatment. Methodology. In this study, the novel rapid workflow of the MALDI Biotypr Sepsityper kit (Bruker Daltonik GmbH, Germany) was evaluated using routine samples from a 2-year period (n=6918), and dedicated optimized protocols for the microbial groups that were more difficult to identify were developed. Moreover, the use of the residual bacterial pellet to perform susceptibility testing using different methods (commercial broth microdilution, disc diffusion, gradient diffusion) was investigated. Results. The rapid Sepsityper protocol allowed the identification of 5470/6338 (86.3 %) monomicrobial samples at species level, with very good performance for all of the clinically most significant pathogens (2510/2592 enterobacteria, 631/669 Staphylococcus aureus and 223/246 enterococci were identified). Streptococcus pneumoniae , Bacteroides fragilis and yeasts were the most troublesome to identify, but the application of specific optimized protocols significantly improved their rate of identification (from 14.7–71.5 %, 47.8–89.7 % and 37.1–89.5 %, respectively). Specificity was 100 % (no identification was made for the false-positive samples). Further, the residual pellet proved to be suitable to investigate susceptibility to antimicrobials, enabling us to simplify the workflow and shorten the time to report. Conclusion. The Rapid Sepsityper workflow proved to be a reliable sample preparation method for identification and susceptibility testing directly from positive blood cultures, providing novel approaches for accelerated diagnostics of bloodstream infections.

Successfully treated infected aneurysm caused by Listeria monocytogenes

“…Earlier, two cases with blood stream infections were diagnosed with L. monocytogenes bacteremia using MALDI-TOF MS-based direct identification using positive blood cultures [ 11 ]. The Verigene® system (Luminex) exhibited high sensitivity (18/18, 100 %) and specificity (1157/1157, 100 %) [ 12 , 13 ]. The MALDI biotyper Sepsityper kit® (Bruker Daltonik GmbH) identifies microorganisms within 30 min, and the Verigene® system (Luminex) identifies microorganisms within 150 min [ 12 , 13 ].…”

“…The Verigene® system (Luminex) exhibited high sensitivity (18/18, 100 %) and specificity (1157/1157, 100 %) [ 12 , 13 ]. The MALDI biotyper Sepsityper kit® (Bruker Daltonik GmbH) identifies microorganisms within 30 min, and the Verigene® system (Luminex) identifies microorganisms within 150 min [ 12 , 13 ]. In our case, we suspected Listeria species, based on the Gram staining within 24 h of obtaining blood cultures; and diagnosed L. monocytogenes -infected aneurysm, based on the rapid diagnostic testing and multidetector computed tomographic angiography finding in addition to the clinical presentation.…”

MALDI-Based Mass Spectrometry in Clinical Testing: Focus on Bacterial Identification

“…Kits have been developed for this purpose. The MALDI Sepsityper ® kit (Bruker Daltonics), which collects bacteria by lysing blood cell components in lysis buffer followed by high-speed centrifugation, is widely used in Japan and overseas [64][65][66][67][68]. An alternative method is to capture and collect bacteria using positively charged polyacrylamide (cationic particles) [69].…”

Identification of micro-organism from positive blood cultures: comparison of three different short culturing methods to the Rapid Sepsityper workflow

“…The Rapid Sepsityper sample preparation was performed following the manufacturer's instructions with slight modifications [20,24]. Briefly, 1 ml of the blood culture sample was transferred to a 1.5 ml tube.…”

“…Furthermore, they also enable the ID of virtually every microbial species detectable by MALDI-TOF MS [9]. The MBT Sepsityper IVD Kit (Bruker Daltonics GmbH and Co KG, Bremen, Germany) is a wide-spread sample preparation method, which proved to have a good efficacy [20][21][22][23], also in its simplified and shortened protocol version (Rapid Sepsityper) [24,25]. Many studies were performed to compare short subculturing to the Sepsityper, showing discordant results in terms of rate of correct ID [26][27][28][29][30][31].…”