Jamalian Azadeh, Freeke Joanna, Chowdhary Anuradha, de Hoog G Sybren, Stielow J Benjamin, Meis Jacques F
Centre of Expertise in Mycology, Radboud UMC/Canisius Wilhelmina Hospital, 6532 SZ Nijmegen, The Netherlands.
Medical Mycology Unit, Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi 110007, India.
J Fungi (Basel). 2023 Feb 16;9(2):267. doi: 10.3390/jof9020267.
The emerging pathogen has been associated with nosocomial outbreaks on six continents. Genetic analysis indicates simultaneous and independent emergence of separate clades of the species in different geographical locations. Both invasive infection and colonization have been observed, warranting attention due to variable antifungal resistance profiles and hospital transmission. MALDI-TOF based identification methods have become routine in hospitals and research institutes. However, identification of the newly emerging lineages of yet remains a diagnostic challenge. In this study an innovative liquid chromatography (LC)-high resolution Orbitrap mass spectrometry method was used for identification of from axenic microbial cultures. A set of 102 strains from all five clades and different body locations were investigated. The results revealed correct identification of all strains within the sample cohort, with an identification accuracy of 99.6% from plate culture, in a time-efficient manner. Furthermore, application of the applied mass spectrometry technology provided the species identification down to clade level, thus potentially providing the possibility for epidemiological surveillance to track pathogen spread. Identification beyond species level is required specially to differentiate between nosocomial transmission and repeated introduction to a hospital.
这种新出现的病原体已与六大洲的医院感染暴发相关。基因分析表明，该物种的不同进化枝在不同地理位置同时且独立出现。已观察到侵袭性感染和定植情况，由于抗真菌耐药谱不同以及医院内传播，这值得关注。基于基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）的鉴定方法已在医院和研究机构中成为常规方法。然而，对该病原体新出现的谱系进行鉴定仍然是一项诊断挑战。在本研究中，一种创新的液相色谱（LC）-高分辨率轨道阱质谱方法被用于从无菌微生物培养物中鉴定该病原体。对来自所有五个进化枝以及不同身体部位的102株菌株进行了研究。结果显示，能高效地正确鉴定样本队列中的所有菌株，平板培养的鉴定准确率为99.6%。此外，所应用的质谱技术可将物种鉴定到进化枝水平，从而有可能为追踪病原体传播的流行病学监测提供可能。特别需要在物种水平以上进行鉴定，以区分医院内传播和多次引入医院的情况。
