1NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, B15 2GW, Birmingham, UK.
2Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, B15 2GW, Birmingham, UK.
Antimicrob Resist Infect Control. 2019 Jan 17;8:14. doi: 10.1186/s13756-019-0470-1. eCollection 2019.
Carbapenemase-producing (CPE) pose a considerable threat to modern medicine. New treatment options and methods to limit spread need to be investigated. Blue light (BL) is intrinsically antimicrobial, and we have previously demonstrated significant antimicrobial effects on biofilms of a panel of isolates, including two CPEs.This study was performed to assess the antibacterial activity of 405 nm BL against a panel of CPE isolates (four encoding , three , two , and three encoding both NDM and OXA-48 carbapenemases).
In vitro experiments were conducted on 72 h old biofilms of CPEs which were exposed to 60 mW/cm of BL. Changes to biofilm seeding were assessed by measuring the optical density of treated and untreated biofilms.
Twelve bacterial clinical isolates (comprising eight , one , and three ) were tested. BL was delivered for 5, 15 and 30 min, achieving doses of 162, 54, and 108 J/cm, respectively.All of the CPEs were susceptible to BL treatment, with increasing reductions in seeding with increasing durations of exposure. At 30 min, reductions in biofilm seeding of ≥80% were observed for 11 of the 12 isolates, compared to five of 12 after 15 min. CPE_8180 was less susceptible than the rest, with a maximum reduction in seeding of 66% at 30 min.
BL is effective at reducing the seeding of mature CPE biofilms in vitro, and offers great promise as a topical decontamination/treatment agent for both clinical and environmental applications.
碳青霉烯酶产生菌（CPE）对现代医学构成了相当大的威胁。需要研究新的治疗选择和方法来限制其传播。蓝光（BL）具有内在的抗菌作用，我们之前已经证明了它对包括两种 CPE 在内的一系列分离株生物膜具有显著的抗菌作用。本研究旨在评估 405nm BL 对一组 CPE 分离株（四种编码 ，三种 ，两种 和三种同时编码 NDM 和 OXA-48 碳青霉烯酶）的抗菌活性。
对 72 小时龄的 CPE 生物膜进行体外实验，用 60mW/cm 的 BL 照射。通过测量处理和未处理生物膜的光密度来评估生物膜接种的变化。
测试了 12 个细菌临床分离株（包括 8 个 ，1 个 和 3 个 ）。BL 照射 5、15 和 30 分钟，分别达到 162、54 和 108J/cm 的剂量。所有的 CPE 都对 BL 治疗敏感，随着暴露时间的延长，接种物的减少也随之增加。在 30 分钟时，与 15 分钟后相比，12 个分离株中的 11 个的生物膜接种减少≥80%，而 12 个中的 5 个减少≥80%。CPE_8180 的敏感性较低，在 30 分钟时的最大接种减少率为 66%。
BL 可有效减少体外成熟 CPE 生物膜的接种，有望成为临床和环境应用的一种局部去污/治疗剂。
