Department of Microbiology, Cliniques universitaires Saint-Luc, Université Catholique de Louvain, Avenue Hippocrate 10, B-1200, Brussels, Belgium.
Department of Microbiology, Clinique Saint-Joseph - CHC, Rue de Hesbaye 75, B-4000, Liège, Belgium.
Eur J Clin Microbiol Infect Dis. 2018 Nov;37(11):2145-2152. doi: 10.1007/s10096-018-3351-2. Epub 2018 Aug 20.
Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) considerably reduces timeframe required from initial blood culture positivity towards complete bacterial identification. However, rapid identification of polymicrobial blood cultures remains challenging. We evaluated the performances of the Bruker® MBT Sepsityper IVD module on MALDI-TOF MS for the direct identification of polymicrobial blood culture bottles. This module has the ability to give a strong indication that a sample contains a mixture of organisms and to identify two of them. Blood culture bottles considered as polymicrobial using routine subculture were collected and processed using the Sepsityper kit. MALDI-TOF MS identification was performed using the MBT Compass IVD software including the Sepsityper module. From 143 polymicrobial blood culture bottles tested, 34.3% (49/143) were completely identified by the module. Both microorganisms were more easily detected by the module in samples containing two pathogens than in samples containing two contaminants (36.8% vs 29.4%). Additionally, in more than half of the samples, the module detected 1 of the different microorganisms contained in the same vial. In these cases, with a pathogen and contaminant in the same sample, the module detected the pathogen in more than 80%. The Sepsityper module identified 14 microorganisms which were not recovered by conventional culture methods. The Bruker® MBT Sepsityper IVD module contributed to a valuable identification of polymicrobial blood cultures in more than a third of all cases. Conventional culture methods are still required to complete the results and to carry on susceptibility testing.
基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）极大地缩短了从初始血培养阳性到完全细菌鉴定所需的时间框架。然而，快速鉴定多微生物血培养物仍然具有挑战性。我们评估了 Bruker®MBT Sepsityper IVD 模块在 MALDI-TOF MS 上直接鉴定多微生物血培养瓶的性能。该模块能够强烈表明样品中含有混合生物体，并鉴定其中两种。使用常规传代培养的多微生物血培养瓶被收集并使用 Sepsityper 试剂盒进行处理。使用 MBT Compass IVD 软件（包括 Sepsityper 模块）进行 MALDI-TOF MS 鉴定。在测试的 143 个多微生物血培养瓶中，34.3%（49/143）被模块完全鉴定。在含有两种病原体的样品中，模块比在含有两种污染物的样品中更容易检测到两种微生物（36.8%比 29.4%）。此外，在超过一半的样品中，模块检测到同一瓶中不同微生物中的 1 种。在这些情况下，在同一样本中存在病原体和污染物，模块检测到的病原体超过 80%。Sepsityper 模块鉴定了 14 种未通过常规培养方法回收的微生物。Bruker®MBT Sepsityper IVD 模块在超过三分之一的情况下有助于多微生物血培养物的有价值鉴定。仍然需要常规培养方法来完成结果并进行药敏试验。
