Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Toruń, Wileńska 4 Str, 87-100, Toruń, Poland.
Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7 Str, 87-100, Toruń, Poland.
Curr Microbiol. 2023 Jul 5;80(8):271. doi: 10.1007/s00284-023-03384-z.
The polymicrobial nature of diabetic foot infection (DFI) makes accurate identification of the DFI microbiota, including rapid detection of drug resistance, challenging. Therefore, the main objective of this study was to apply matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOF MS) technique accompanied by multiply culture conditions to determine the microbial patterns of DFIs, as well as to assess the occurrence of drug resistance among Gram-negative bacterial isolates considered a significant cause of the multidrug resistance spread. Furthermore, the results were compared with those obtained using molecular techniques (16S rDNA sequencing, multiplex PCR targeting drug resistance genes) and conventional antibiotic resistance detection methods (Etest strips). The applied MALDI-based method revealed that, by far, most of the infections were polymicrobial (97%) and involved many Gram-positive and -negative bacterial species-19 genera and 16 families in total, mostly Enterobacteriaceae (24.3%), Staphylococcaceae (20.7%), and Enterococcaceae (19.8%). MALDI drug-resistance assay was characterized by higher rate of extended-spectrum beta-lactamases (ESBLs) and carbapenemases producers compared to the reference methods (respectively 31% and 10% compared to 21% and 2%) and revealed that both the incidence of drug resistance and the species composition of DFI were dependent on the antibiotic therapy used. MALDI approach included antibiotic resistance assay and multiply culture conditions provides microbial identification at the level of DNA sequencing, allow isolation of both common (eg. Enterococcus faecalis) and rare (such as Myroides odoratimimus) bacterial species, and is effective in detecting antibiotic-resistance, especially those of particular interest-ESBLs and carbapenemases.
糖尿病足感染（DFI）的多微生物性质使得准确识别 DFI 微生物群，包括快速检测耐药性，具有挑战性。因此，本研究的主要目的是应用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）技术结合多种培养条件来确定 DFI 的微生物模式，以及评估被认为是多药耐药传播的重要原因的革兰氏阴性细菌分离物中耐药性的发生。此外，将结果与分子技术（16S rDNA 测序、针对耐药基因的多重 PCR）和常规抗生素耐药检测方法（Etest 条带）的结果进行比较。应用的基于 MALDI 的方法表明，迄今为止，大多数感染是多微生物的（97%），涉及许多革兰氏阳性和阴性细菌种属-总共 19 个属和 16 个科，主要是肠杆菌科（24.3%）、葡萄球菌科（20.7%）和肠球菌科（19.8%）。MALDI 耐药性测定法的特点是与参考方法相比，产生超广谱β-内酰胺酶（ESBLs）和碳青霉烯酶的比例更高（分别为 31%和 10%，而分别为 21%和 2%），并且表明 DFI 的耐药发生率和物种组成均取决于抗生素治疗。MALDI 方法包括抗生素耐药性测定法和多种培养条件，可在 DNA 测序水平上提供微生物鉴定，可分离常见（例如粪肠球菌）和罕见（如恶臭假单胞菌）细菌种属，并且在检测抗生素耐药性方面非常有效，尤其是那些特别关注的耐药性-ESBLs 和碳青霉烯酶。
