An evaluation of three processing methods and the effect of reduced culture times for faster direct identification of pathogens from BacT/ALERT blood cultures by MALDI-TOF MS

被引:0
作者
A. J. M. Loonen
A. R. Jansz
J. Stalpers
P. F. G. Wolffs
A. J. C. van den Brule
机构
[1] PAMM Laboratories,Department of Medical Microbiology
[2] Fontys University of Applied Science,Department of Medical Molecular Diagnostics
[3] Maastricht University Medical Centre,Department of Medical Microbiology
[4] CAPHRI,Laboratory for Molecular Diagnostics, Departments of Medical Microbiology and Pathology
[5] Jeroen Bosch Hospital,undefined
来源
European Journal of Clinical Microbiology & Infectious Diseases | 2012年 / 31卷
关键词
Blood Culture; Positive Blood Culture; Blood Culture Bottle; Serum Separation Tube; Correct Identification Rate;
D O I
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学科分类号
摘要
Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) is a fast and reliable method for the identification of bacteria from agar media. Direct identification from positive blood cultures should decrease the time to obtaining the result. In this study, three different processing methods for the rapid direct identification of bacteria from positive blood culture bottles were compared. In total, 101 positive aerobe BacT/ALERT bottles were included in this study. Aliquots from all bottles were used for three bacterial processing methods, i.e. the commercially available Bruker’s MALDI Sepsityper kit, the commercially available Molzym’s MolYsis Basic5 kit and a centrifugation/washing method. In addition, the best method was used to evaluate the possibility of MALDI application after a reduced incubation time of 7 h of Staphylococcus aureus- and Escherichia coli-spiked (1,000, 100 and 10 colony-forming units [CFU]) aerobe BacT/ALERT blood cultures. Sixty-six (65%), 51 (50.5%) and 79 (78%) bottles were identified correctly at the species level when the centrifugation/washing method, MolYsis Basic 5 and Sepsityper were used, respectively. Incorrect identification was obtained in 35 (35%), 50 (49.5%) and 22 (22%) bottles, respectively. Gram-positive cocci were correctly identified in 33/52 (64%) of the cases. However, Gram-negative rods showed a correct identification in 45/47 (96%) of all bottles when the Sepsityper kit was used. Seven hours of pre-incubation of S. aureus- and E. coli-spiked aerobe BacT/ALERT blood cultures never resulted in reliable identification with MALDI-TOF MS. Sepsityper is superior for the direct identification of microorganisms from aerobe BacT/ALERT bottles. Gram-negative pathogens show better results compared to Gram-positive bacteria. Reduced incubation followed by MALDI-TOF MS did not result in faster reliable identification.
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页码:1575 / 1583
页数:8
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共 142 条
[11]  
Peters C(2011)Rapid identification of bacteria in positive blood culture broths by matrix-assisted laser desorption ionization-time of flight mass spectrometry Clin Microbiol Infect 17 546-551
[12]  
Ahsan M(2009)Microorganisms direct identification from blood culture by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry PLoS One 4 e8041-1483
[13]  
Chateau D(2010)Direct identification of bacteria in positive blood culture bottles by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry J Clin Microbiol 48 1481-1638
[14]  
Kumar A(2010)Matrix-assisted laser desorption ionization-time of flight mass spectrometry for direct bacterial identification from positive blood culture pellets Clin Microbiol Infect 16 1631-1591
[15]  
Roberts D(2010)Matrix-assisted laser desorption ionization time-of-flight mass spectrometry identifies 90% of bacteria directly from blood culture vials J Clin Microbiol 48 1584-1548
[16]  
Wood KE(2010)Rapid identification of bacteria from positive blood culture bottles by use of matrix-assisted laser desorption-ionization time of flight mass spectrometry fingerprinting J Clin Microbiol 48 1542-195
[17]  
Light B(2011)Real-time identification of bacteria and Clin Microbiol Infect 17 192-2631
[18]  
Parrillo JE(2009) species in positive blood culture broths by matrix-assisted laser desorption ionization-time of flight mass spectrometry J Clin Microbiol 47 2629-3451
[19]  
Sharma S(2001)The sensitivity of direct identification from positive BacT/ALERT™ (bioMérieux) blood culture bottles by matrix-assisted laser desorption ionization time-of-flight mass spectrometry is low J Clin Microbiol 39 3446-95
[20]  
Suppes R(2010)Evaluation of new preanalysis sample treatment tools and DNA isolation protocols to improve bacterial pathogen detection in whole blood Eur J Clin Microbiol Infect Dis 29 89-54