Antimicrobial and antifouling efficacy of urinary catheters impregnated with a combination of macrolide and fluoroquinolone antibiotics against Pseudomonas aeruginosa

The incidence of catheter associated urinary tract infections (CAUTIs) is increasing worldwide. This study was designed to modify a biomaterial by impregnating a silicone urinary catheter with combination of a macrolide, azithromycin (AZM) and a fluoroquinolone, ciprofloxacin (CIP). Drug release profiles showed slow yet continuous release of antibiotics from catheters for one month. In vitro efficacy testing showed that group B catheters [3% (w v−1) CIP + 6% (w v−1) AZM] outperformed group A catheters [2% (w v−1) CIP + 5% (w v−1) AZM] by (1) showing larger zones of inhibition (>31 mm) compared to group A (Pseudomonas aeruginosa PAO1; (2) killing adhered bacteria in 24 h compared to 24–48 h in group A; (3) showing longer antimicrobial durability for four weeks; and (4) exhibiting a stable real-time shelf life of one year, suggesting that these catheters can be explored in clinical settings, especially in long-term CAUTI.

全球范围内导管相关性尿路感染（catheter associated urinary tract infections, CAUTIs）的发病率呈上升态势。本研究通过将大环内酯类（macrolide）药物阿奇霉素（azithromycin, AZM）与氟喹诺酮类（fluoroquinolone）药物环丙沙星（ciprofloxacin, CIP）联合浸渍于硅胶导尿管（silicone urinary catheter）中，完成对生物材料的改性。药物释放曲线结果显示，负载的抗生素可实现缓慢且持续的释放，释放时长可达1个月。体外药效试验表明，B组导尿管[3%(w/v) CIP + 6%(w/v) AZM]的性能优于A组导尿管[2%(w/v) CIP + 5%(w/v) AZM]，具体体现在以下四方面：(1) 针对铜绿假单胞菌PAO1（Pseudomonas aeruginosa PAO1）的抑菌圈直径大于31 mm，优于A组；(2) 可在24小时内杀灭黏附于导尿管的细菌，而A组需要24~48小时；(3) 抗菌持久性更长，可达4周；(4) 具备稳定的1年货架期。上述结果提示，此类改性导尿管可在临床场景中开展进一步探索，尤其适用于长期导管相关性尿路感染的防控。