Stickler David J
Cardiff School of Biosciences, Main Building, Cardiff University, Museum Avenue, Cardiff CF103TL, UK.
Nat Clin Pract Urol. 2008 Nov;5(11):598-608. doi: 10.1038/ncpuro1231. Epub 2008 Oct 14.
Bacteria have a basic survival strategy: to colonize surfaces and grow as biofilm communities embedded in a gel-like polysaccharide matrix. The catheterized urinary tract provides ideal conditions for the development of enormous biofilm populations. Many bacterial species colonize indwelling catheters as biofilms, inducing complications in patients' care. The most troublesome complications are the crystalline biofilms that can occlude the catheter lumen and trigger episodes of pyelonephritis and septicemia. The crystalline biofilms result from infection by urease-producing bacteria, particularly Proteus mirabilis. Urease raises the urinary pH and drives the formation of calcium phosphate and magnesium phosphate crystals in the biofilm. All types of catheter are vulnerable to encrustation by these biofilms, and clinical prevention strategies are clearly needed, as bacteria growing in the biofilm mode are resistant to antibiotics. Evidence indicates that treatment of symptomatic, catheter-associated urinary tract infection is more effective if biofilm-laden catheters are changed before antibiotic treatment is initiated. Infection with P. mirabilis exposes the many faults of currently available catheters, and plenty of scope exists for improvement in both their design and production; manufacturers should take up the challenge to improve patient outcomes.
在表面定殖，并以嵌入凝胶状多糖基质中的生物膜群落形式生长。导尿管插入的尿道为大量生物膜群体的形成提供了理想条件。许多细菌物种以生物膜的形式定殖在留置导尿管上，引发患者护理中的并发症。最麻烦的并发症是结晶性生物膜，它会阻塞导管腔，并引发肾盂肾炎和败血症。结晶性生物膜是由产脲酶细菌感染引起的，尤其是奇异变形杆菌。脲酶会提高尿液的pH值，并促使生物膜中磷酸钙和磷酸镁晶体的形成。所有类型的导管都容易被这些生物膜结壳，显然需要临床预防策略，因为以生物膜模式生长的细菌对抗生素具有抗性。有证据表明，如果在开始抗生素治疗前更换载有生物膜的导管，对有症状的导管相关性尿路感染的治疗会更有效。奇异变形杆菌感染暴露了目前可用导管的诸多缺陷，在其设计和生产方面有很大的改进空间；制造商应迎接挑战，以改善患者的治疗结果。
