Abstract：
Many methods are being tried for rapid and accurate identification of sepsis-causing microorganisms. We analyzed the performance of three different preparation methods [MBT Sepsityper IVD Kit (Bruker Daltonics GmbH, Germany), sodium dodecyl sulfate (SDS) lysis, and differential centrifugation with protein extraction (Centrifugation +PE)] and compared in standard and Sepsityper modules of the Bruker Biotyper MALDI-TOF MS for direct identification of bacteria from 240 positive blood culture bottles of BACTEC FX (Becton Dickinson, USA). By using the standard module, correct identification at species level (score ≥2) was done in 46.7% of the samples with SDS lysis, 44.2% with centrifugation +PE, and 25.4% with the Sepsityper kit. These ratios at the genus level (score range 1.70-1.99) were 34.6%, 31.3%, and 32.5%, respectively. With SDS lysis (195), more bacteria were identified correctly than centrifugation +PE (181) and the Sepsityper kit (139). A statistically significant difference was found between SDS and the Sepsityper kit and Centrifugation +PE and the Sepsityper kit (P < 0.001, both). By using the Sepsityper module, correct identification at species level (score ≥1.8) was determined in 74.2% of the samples with SDS lysis and centrifugation +PE each and 55% with the Sepsityper kit. These ratios at the genus level (score range 1.60-1.79) were 16.3%, 10%, and 19.2%, respectively. SDS lysis (217) had significantly higher identification rates than centrifugation +PE (202) and the Sepsityper kit (178) (P = 0.028 and P < 0.001). A statistically significant difference was also observed between centrifugation +PE and the Sepsityper kit (P < 0.001). Best performance was obtained with SDS lysis among the methods. Although better performance was achieved by using Sepsityper software module, risk of misidentification should not be ignored.
OBJECTIVE: Sepsis is a life-threatening condition, and rapid and accurate identification of the causative microorganisms from blood cultures is crucial for timely and effective treatment. Although there are many studies on direct identification from blood cultures with MALDI-TOF MS, further standardization is still needed. In our study, we analyzed the performance of three different preparation methods and compared by using two analysis modules of the Bruker Biotyper MALDI-TOF MS for direct identification of bacteria from numerous positive blood culture bottles. The literature reports a limited number of studies that compare different preparation methods for direct blood culture identification, processing a large number of blood samples concurrently and evaluating the same samples as in our study. Moreover, although SDS is used very frequently in medical laboratories, there are few studies on direct identification from blood culture bottles. In our study, the highest correct identification rate was observed with the SDS method.
OBJECTIVE: Sepsis is a life-threatening condition, and rapid and accurate identification of the causative microorganisms from blood cultures is crucial for timely and effective treatment. Although there are many studies on direct identification from blood cultures with MALDI-TOF MS, further standardization is still needed. In our study, we analyzed the performance of three different preparation methods and compared by using two analysis modules of the Bruker Biotyper MALDI-TOF MS for direct identification of bacteria from numerous positive blood culture bottles. The literature reports a limited number of studies that compare different preparation methods for direct blood culture identification, processing a large number of blood samples concurrently and evaluating the same samples as in our study. Moreover, although SDS is used very frequently in medical laboratories, there are few studies on direct identification from blood culture bottles. In our study, the highest correct identification rate was observed with the SDS method.
摘要：
正在尝试许多方法来快速和准确地鉴定引起败血症的微生物。我们分析了三种不同制备方法的性能[MBTSepsityperIVDKit(BrukerDaltonicsGmbH，德国),十二烷基硫酸钠（SDS）裂解，和蛋白质提取的差速离心（离心PE）]，并在BrukerBiotyperMALDI-TOFMS的标准和Sepsityper模块中进行了比较，以直接鉴定来自240个BACTECFX阳性血液培养瓶的细菌（BectonDickinson，美国）。通过使用标准模块，在SDS裂解的46.7％的样品中，在物种水平（评分≥2）进行了正确的鉴定，44.2%离心+PE,和25.4%与Sepsityper套件。这些比例在属水平（得分范围为1.70-1.99）为34.6％，31.3%,32.5%,分别。用SDS裂解(195)，与离心+PE(181)和Sepsityper试剂盒(139)相比，更多的细菌被正确鉴定。在SDS和Sepsityper试剂盒以及离心+PE和Sepsityper试剂盒之间发现了统计学上的显着差异（P<0.001，两者）。通过使用Sepsityper模块，74.2%的样本采用SDS裂解和离心+PE,55%的样本采用Sepsityper试剂盒进行了物种水平的正确鉴定(评分≥1.8).这些比例在属水平（得分范围为1.60-1.79）为16.3％，10%,和19.2%，分别。SDS裂解(217)的识别率显著高于离心+PE(202)和Sepsityper试剂盒(178)(P=0.028和P<0.001)。在离心+PE和Sepsityper试剂盒之间也观察到统计学上的显著差异(P<0.001)。在这些方法中,用SDS裂解获得最佳性能。尽管使用Sepsityper软件模块实现了更好的性能，不应忽视错误识别的风险。
目的：脓毒症是一种危及生命的疾病，从血液培养物中快速准确地鉴定致病微生物对于及时有效的治疗至关重要。尽管有许多关于使用MALDI-TOFMS从血液培养物中直接鉴定的研究，仍然需要进一步标准化。在我们的研究中,我们分析了三种不同制备方法的性能,并通过使用BrukerBiotyperMALDI-TOFMS的两个分析模块对众多阳性血培养瓶中细菌的直接鉴定进行了比较.文献报道了有限数量的研究，这些研究比较了直接血培养鉴定的不同制备方法，同时处理大量血液样本，并评估与我们研究相同的样本。此外，尽管SDS在医学实验室中使用非常频繁，关于从血液培养瓶中直接鉴定的研究很少。在我们的研究中,SDS法的正确识别率最高。
目的：脓毒症是一种危及生命的疾病，从血液培养物中快速准确地鉴定致病微生物对于及时有效的治疗至关重要。尽管有许多关于使用MALDI-TOFMS从血液培养物中直接鉴定的研究，仍然需要进一步标准化。在我们的研究中,我们分析了三种不同制备方法的性能,并通过使用BrukerBiotyperMALDI-TOFMS的两个分析模块对众多阳性血培养瓶中细菌的直接鉴定进行了比较.文献报道了有限数量的研究，这些研究比较了直接血培养鉴定的不同制备方法，同时处理大量血液样本，并评估与我们研究相同的样本。此外，尽管SDS在医学实验室中使用非常频繁，关于从血液培养瓶中直接鉴定的研究很少。在我们的研究中,SDS法的正确识别率最高。
