Mansouri M David, Ramanthan Venkat, Mansouri Dena L, Hull Richard A
Baylor College of Medicine, Houston, Texas, USA.
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, USA.
J Appl Microbiol. 2022 May;132(5):3915-3924. doi: 10.1111/jam.15490. Epub 2022 Feb 26.
Since management of catheter-associated infections, which are generally biofilm-based, is attempted in certain patients such as older and frail patients by using a catheter lock solution (CLS), we examined the combination of N-acetyl cysteine (NAC), an antibiofilm agent, and levofloxacin, a broad-spectrum antimicrobial agent, for this purpose.
Intravascular catheters were colonized with methicillin-resistant Staphylococcus epidermidis, levofloxacin-sensitive/methicillin-resistant Staph. aureus, levofloxacin-resistant/methicillin-resistant Staph. aureus, vancomycin-resistant Enterococcus, Escherichia coli, Klebsiella pneumoniae or Pseudomonas aeruginosa and treated with a CLS containing normal saline, NAC, levofloxacin or NAC plus levofloxacin (NACLEV) and then cultured to assess their antimicrobial activities. We also examined antibiofilm and antimicrobial activities of each CLS by scanning electron microscopy (SEM) and the mechanical integrity of catheters exposed to CLS. Treatment of colonized catheters with NACLEV-CLS significantly reduced colonization (p < 0.005) against all pathogens. SEM images also indicate reduction in colonization with NACLEV-CLS with considerable reduction in both visible bacteria and the associated biofilm. Mean tensile strength of catheters exposed to CLS was not significantly different compared to controls (p > 0.05).
These in vitro results suggest that NACLEV-CLS can significantly reduce all bacterial colonization and potentially help salvage infected catheters without affecting the catheter's mechanical integrity.
This study presents a novel CLS with a broad spectrum of antimicrobial activity against catheter-associated infections, particularly in long-term catheters.
由于导管相关感染通常基于生物膜形成，在某些患者（如老年体弱患者）中尝试使用导管锁溶液（CLS）进行管理，因此我们为此研究了抗生物膜剂N - 乙酰半胱氨酸（NAC）和广谱抗菌剂左氧氟沙星的组合。
血管内导管被耐甲氧西林表皮葡萄球菌、左氧氟沙星敏感/耐甲氧西林金黄色葡萄球菌、左氧氟沙星耐药/耐甲氧西林金黄色葡萄球菌、耐万古霉素肠球菌、大肠杆菌、肺炎克雷伯菌或铜绿假单胞菌定植，并用含有生理盐水、NAC、左氧氟沙星或NAC加左氧氟沙星（NACLEV）的CLS进行处理，然后培养以评估其抗菌活性。我们还通过扫描电子显微镜（SEM）检查了每种CLS的抗生物膜和抗菌活性以及暴露于CLS的导管的机械完整性。用NACLEV - CLS处理定植的导管可显著降低对所有病原体的定植（p < 0.005）。SEM图像也表明NACLEV - CLS可减少定植，可见细菌和相关生物膜均有显著减少。暴露于CLS的导管的平均拉伸强度与对照组相比无显著差异（p > 0.05）。
这些体外结果表明，NACLEV - CLS可显著减少所有细菌定植，并可能有助于挽救感染的导管，而不影响导管的机械完整性。
本研究提出了一种新型CLS，对导管相关感染具有广谱抗菌活性，特别是对长期导管。
