March Rosselló Gabriel Alberto, Gutiérrez Rodríguez María Purificación, Ortiz de Lejarazu Leonardo Raúl, Orduña Domingo Antonio, Bratos Pérez Miguel Ángel
Departmento de Microbiología, Facultad de Medicina, Universidad de Valladolid, Spain.
Departmento de Microbiología, Facultad de Medicina, Universidad de Valladolid, Spain.
Enferm Infecc Microbiol Clin. 2015 Feb;33(2):89-94. doi: 10.1016/j.eimc.2014.02.022. Epub 2014 May 3.
Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry is widely established as a technique in clinical microbiology laboratories for the identification of microorganisms. Using this technique, it is also possible to obtain the identification of microorganisms from untreated urine samples.
In this study, a differential centrifugation protocol and a criterion for validation of the results in order to achieve microbial identification from untreated urine samples are proposed. Additionally, the sensitivity of the analytical procedure in monobacterial urine samples has been evaluated.
A 90% sensitivity (confidence interval of 81.96%-94.84%) was obtained in urine samples with bacterial counts of ≥1×10(5)CFU/ml, and it was possible to improve the percentages of direct identifications from urine samples with bacterial counts of <1×10(5)CFU/ml.
It is concluded that the MALDI-TOF system is both fast and reliable in the identification of individual microorganisms from untreated urine samples with counts of ≥1×10(5)CFU/ml.
基质辅助激光解吸/电离飞行时间（MALDI-TOF）质谱分析法在临床微生物实验室中作为一种鉴定微生物的技术已被广泛应用。使用该技术，也能够从未经处理的尿液样本中鉴定出微生物。
在本研究中，提出了一种差速离心方案以及结果验证标准，以便从未经处理的尿液样本中实现微生物鉴定。此外，还评估了该分析程序在单一细菌尿液样本中的灵敏度。
在细菌计数≥1×10⁵CFU/ml的尿液样本中获得了90%的灵敏度（置信区间为81.96%-94.84%），并且有可能提高细菌计数<1×10⁵CFU/ml的尿液样本直接鉴定的百分比。
得出结论，MALDI-TOF系统在从未经处理、细菌计数≥1×10⁵CFU/ml的尿液样本中鉴定单个微生物方面既快速又可靠。
