Zakażenia układu moczowego z udziałem Proteus mirabilis – rola biofilmu i inkrustacji cewnika urologicznego

Urinary tract infections caused by Proteus mirabilis – role of the biofilm and the encrustation of the urological catheter
D. M. Matusiak

1. Zakażenia układu moczowego. 2. Proteus mirabilis – charakterystyka ogólna. 3. Biofilm – definicja, opis. 4. Biofilm na cewniku urologicznym i jego inkrustacja. 5. Zapobieganie i leczenie CAUTI u osób poddanych cewnikowaniu. 6. Podsumowanie

Abstract: Urinary tract infection (UTI) is one of the most common nosocomial infections. Proteus mirabilis is important Gram-negative, dimorphic and motile pathogen (Enterobacteriaceae family), causing UTI – especially in catheterized patients. Key elements leading to CAUTI are: catheter colonization, mono- or multi-species biofilm formation and the long period of the catherization. Biofilm is microorganisms’ protective and dynamic community, attached to surface and embedded in extracellular matrix (mainly polysaccharides). P. mirabilis can easily adhere to catheter surface and cause it’s encrustation and blockage (due to urine alkalization by urease, leading to struvite and apatite crystals precipitation). Struvite contains magnesium ammonium phosphate and apatite – calcium phosphate. Urine flow obstruction can elicit pyelonephritis. Other uropathogens, producing urease e.g. Morganella morganii, Providencia stuartii, Escherichia coli (some strains), Klebsiella pneumoniae rather rarely cause catheter blockage. There have been proposed many solutions, preventing catheter biofilm colonization or disrupting formed consortium. However by this time there is no high-effective and broadly used remedy. One of the solutions is the impregnation of the catheters with silver, EDTA, antiseptics (e.g. triclosan, chlorohexidine), antibiotics, heparin or lactoferrin – short-term and insufficient-concentration release, risk of the resistance onset, sometimes non-wide spectrum activity. This solutions are generally moderately effective and postpones the emergence of bacteruria. Another approach (experimental) for example is to inhibit urease or the quorum sensing. The surface of the catheter also could be more hydrophilic and smooth, to inhibit the bacterial attachment.

1. Urinary tract infections. 2. Proteus mirabilis – general description. 3. Biofilm – definition, characterization. 4. Biofilm on urinary catheter and it’s encrustation. 5. Prophylaxis and treatment of CAUTI in catheterized patients. 6. Summary